The Neotropical species of the genus Somoleptus Sharp, 1885 (Coleoptera: Staphylinidae: Staphylininae: Xantholinini)

At present, 45 Somoleptus species are known from the Neotropical region. Among these, 28 species are newly described here, whereas 18 were described in the past. The new species are: S. admirabilis spec. nov., S. andersoni spec. nov., S. ashei spec. nov., S. beniensis spec. nov., S. brevipennis spec. nov., S. breviusculus spec. nov., S. brooksi spec. nov., S. brunneus spec. nov., S. curtipennis spec. nov., S. curtulus spec. nov., S. elongatulus spec. nov., S. gigas spec. nov., S. grandiconus spec. nov., S. humicola spec. nov., S. longiceps spec. nov., S. loretensis spec. nov., S. maximus spec. nov., S. melanarius spec. nov., S. mexicanus spec. nov., S. montanus spec. nov., S. oculatus spec. nov., S. ovatus spec. nov., S. pecki spec. nov., S. peruanus spec. nov., S. recurvatus spec. nov., S. struyvei spec. nov., S. triangulus spec. nov., S. tschirnhausi spec. nov. Four species are transferred from the genus Lithocharodes. These are S. cavicola (Blackwelder, 1943) comb. nov., S. strigulata (Blackwelder 1943) comb. nov., S. longicollis (LeConte, 1863) comb. nov., and S. subtilis (Erichson, 1839) comb. nov. Somoleptus dichiformis Bernhauer, 1910 could not be assigned to either Lithocharodes or Somoleptus. Thus, this species must be treated as species incertae sedis. Two species groups could be differentiated due to the structure of the parameres and the aedeagal cones; one mainly occurs in South America, the second in Central America.


Introduction
In his work on the Central American Staphylinidae, Sharp (1885) described the new genus Somoleptus based on several Central American and one South American species. He separated it from the similar genus Lithocharodes (Sharp, 1876). The assignment of species to one of the two genera was mixed several times in the past. The characterisation and differentiation were described in the revision of the Neotropical Lithocharodes species (Irmler 2021). It mainly based on the structure of the aedeagus, which is more consistent than the external characters proposed by Navarrete-Heredia et al. (2002). After the revision of the Neotropical species of Lithocharodes (Irmler 2021), it seems necessary to work also on a revision of the Neotropical Somoleptus species for a clear assignment of the species to one of the genera. The results of this work are presented here. Overall, if the species described in the past and the new species described here are combined, a number of 45 species will be known from the Neotropical region. One species must be assigned as species incertae sedis: S. dichiformis Bernhauer, 1910. The type specimen of S. dichiformis Bernhauer, 1910 deposited in Field Museum of Natural History (Chicago, U.S.A.) is a male, but the structure of the aedeagus neither fits the aedeagal structures of Somoleptus nor that of Lithocharodes.
In the study on the Neotropical genus Lithocharodes Sharp, 1876, Irmler (2021 differentiated the genera Lithocharodes and Somoleptus mainly by the structure of the aedeagus. In contrast to Lithocharodes, Somoleptus species have a process at the apical orifice of the central lobe. The study of the Somoleptus material results in some more adeagal characters that allowed to separate species groups. These are structures of the parameres, which are either bilobed or unilobed, structures of the process at apical orifice, location of apical cones outside or inside the central lobe, and presence or absence of a sclerotised endophallus. Two major groups can be differentiated: laevis-group and longicollis-group. The laevis-group has a simple, usually uni-lobed paramere; cones at the apical orifice variable, but do not have the characteristic cone-like structure of the longicollis-group. They can be extremely elongate, such as in S. laevis Bernhauer, 1908 or very short and inside the apical orifice, such as in S. breviusculus spec. nov. Only three species have bilobed parameres, such as in S. agraeformis Sharp, 1885. But the outer lobe of the parameres of these species are slender and elongate in contrast to the broader and more circular outer lobe in the longicollis-group. These species may be considered as transitional between both groups. In total, at least 18 species are assigned to the laevis-group. The longicollis-group is much more uniform in the structure of the parameres and the process at the apical orifice of the aedeagus. In this group, the parameres are bilobed with a slender or short and broad, often nearly circular outer lobe. The process has a typical cone-like structure with crowns of stacked spines (Fig. 1c). In addition, the endophallus is very uniform and mainly differs in the form and number of loops. In total, at least 24 species can be assigned to this group, which are in many cases extremely difficult to identify. The species of the laevis-group can be subdivided into three subgroups with closer related species. These are the aenescens-subgroup, which is characterised by a typical laminated brush-like process at the apical orifice of the aedeagus (Fig. 1d). Four species can be assigned to this subgroup (S. aenescens, S. beniensis, S. pulcher, S. recurvatus). Another subgroup consists of the species S. curtulus, S. adimirabilis, S. agraeformis, and S. nitidus (Sharp). In these four species the endophallus of the aedeagus is not sclerotised and the process varies but is similarly cone-like as in the longicollis-group. A third subgroup is formed by S. peruanus, S. struyvei, S. breviusculus, and S. montanus. In the four species, the process at the apical orifice is shifted to the inner side of the orifice (Fig. 1e).
Head: 0.97 mm long, 0.75 mm wide; eyes short, not prominent, postocular sides slightly divergent posteriad; PS : E ratio 6.5; posterior angles combined with posterior margin semi-circular; setiferous punctation dense and moderately deep; without impunctate midline; on average, interstices between punctures as wide as diameter of punctures; partly denser; surface with weak isodiametric microsculpture; shiny. Antennae with first antennomere half-length of head; second and third antennomere conical, twice as long as wide; following antennomeres wider than long and increasing in width; fourth antennomere twice as wide as long; tenth antennomere 2.5 times as wide as long; all antennomeres pubescent. Pronotum: 1.18 mm long, 0.71 mm wide; widest slightly behind anterior third; anteriad narrowed to neck in convex curve; posteriad nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation as dense as on head but slightly finer; wide midline impunctate; surface without microsculpture; polished. Elytra: 0.70 mm long; 0.78 mm wide; without humeral angles; posterior angles rectangular; posterior margin triangularly retreated to suture; setiferous punctation deep and dense; on average, interstices less than half as wide as diameter of punctures; at base partly coriaceous; surface partly with irregular ground-sculpture; matt. Abdomen with dense setiferous punctation; weaker than on elytra; surface with transverse reticulate microsculpture; posterior margin of male sternite VII with triangular incision; posterior margin of male tergite VII straight. Aedeagus oval; between apical cones with short triangular central tooth; cones broad; C : A ratio 0.27; endophallus transparent, not sclerotised; parameres twice as long as apical cones; broad at base; narrowed to acute apex in apical third; with numerous sensillae.

Etymology:
The species name is derived from the Latin admirabilis meaning astonishing or strange and refers to the aedeagus with the non-sclerotised endophallus. Sharp, 1885 Figs 6a-d, 46 B Somoleptus aenescens Sharp, 1885: 495 Type material examined: male, here designated as lectotype: Guatemala, Vera Paz, San Geronimo, leg. Champion (BMNH). 2 female syntypes, 2 male syntypes with same data as lectotype (BMNH); within the loan of the BMNH four specimens were fixed on one plate and one female on a separate plate but from the same location. The 4 specimens of the plate were separated, dissected and one male was labelled as lectotype.

Diagnosis:
The species is characterised by its dark colour combined with the polished glossy surface. In particular, the cones at the orifice of the aedeagus and the shape of the parameres are specific and in common with the other species of the aenescens-subgroup. Within this subgroup, the triangular parameres and the semi-circular emargination of male sternite VII characterises the species among the other species of the subgroup. Description: Length: 5.6 mm. Colouration: Blackish; abdomen lighter brown; pronotum slightly lighter, but still blackish; legs and antennae yellowish-brown. Head: 0.91 mm long, 0.71 mm wide; eyes moderately short; PS : E ratio 3.3; postocular sides nearly parallel; posterior angles widely rounded; Posterior margin convex; setiferous punctation sparse and moderately deep; on average, interstices between punctures twice as wide as diameter of punctures; surface without microsculpture; polished. Antennae with first antennomere as long as half head-length; second and third antennomere conical; twice as long as wide; following antennomeres wider than long and increasing in width; fourth antennomere slightly wider than long; tenth antennomere twice as wide as long; all antennomeres pubescent. Pronotum: 1.02 mm long, 0.65 mm wide; widest shortly behind anterior third; anteriorly sides narrowed in convex curve; in posterior half nearly parallel; posterior angles sub-rectangular; posterior margin slightly curved; setiferous punctation sparse and moderately deep; wide midline impunctate; near anterior margin, impunctate midline convergent; surface without microsculpture; polished. Elytra: 0.96 mm long, 0.90 mm wide; humeral and posterior angles sub-rectangular; posterior margin convexly curved; sides slightly divergent; setiferous punctation distinctly denser and deeper than on head and pronotum; on average, interstices between punctures as wide as diameter of punctures; surface with weak isodiametric microsculpture; less shiny than pronotum. Abdomen much denser punctate than fore-body; male sternite VII with semi-circular emargination at posterior margin; male tergite VII straight. Metatarsus with three subapical ctenidia. Aedeagus oval; endophallus curled; covered by numerous minute teeth; cones at orifice broad and angled; C : A ratio 0.3; contiguous to endophallus; parameres short; triangular; at outer edge with smooth convex curve; at inner edge with two concave emarginations; with numerous sensillae in anterior half. Sharp, 1885 Figs 14a-d, 46 B Somoleptus agraeformis Sharp, 1885: 498 Type material examined: female, syntype: Mexico, leg. Flohr (BMNH).

Diagnosis:
The species is characterised by the narrow neck in combination with the strongly narrowed head and pronotum, which certainly resembles the overall shape of the carabid beetle Agra. Moreover, the short aedeagus with the long cones is species specific.
Description: Length: 4.6 mm. Colouration: Blackish, pronotum and abdomen brown; legs and antennae yellowish brown. Head: 0.76 mm long, 0.54 mm wide; eyes moderately large; PS : E ratio 2.5; postocular sides widely curved to neck; without posterior angles; setiferous punctation moderately dense and deep; on average, interstices between punctures 1.5 times as wide as diameter of punctures; punctation on vertex slightly sparser than laterally; anteriorly on small central area impunctate; surface without microsculpture; polished. Antennae with first antennomere half as long as head; second and third antennomere elongate and conical; combined half as long as first antennomere; following antennomeres wider than long and increasing in width; twice as wide as long. Pronotum: 0.90 mm long, 0.51 mm wide; widest closely in front of middle; sides anteriad continuously convergent; posteriad nearly parallel; posterior angles obtusely rounded; posterior margin slightly convex; setiferous punctation moderately deep and dense; on average, interstices twice as wide as diameter of punctures; wide midline impunctate; impunctate midline anteriorly convergent; surface without microsculpture; polished; Elytra: 0.85 mm long, 0.68 mm wide; humeral and posterior angles sub-rectangular; sides nearly parallel; very slightly curved; posterior margin slightly retreated to suture; setiferous punctation denser and deeper than on head and pronotum; on average, interstices between punctures as wide as diameter of punctures; surface with weak isodiametric microsculpture; less glossy than head and pronotum; Abdomen with dense and moderately deep setiferous punctation; setae long and dark; surface with weak microsculpture; as shiny as elytra; male sternite VII with short central triangular emargination; male tergite VII with straight posterior margin. Metatibia with one subapical ctenidium. Aedeagus small; nearly circular; without sclerotised endophallus; C : ratio 0.8; parameres with inner lobe elongate; longer than cones; outer lobe as large plate; as long as cones. Sharp, 1885 Figs 22a-d, 46 D Somoleptus alticola Sharp, 1885: 498 Type material examined: female, holotype: Guatemala: Totonicapam, 8000-10,500 ft. elev., leg. Champion (BMNH).

Diagnosis:
The species is characterised by the extremely short eyes with postocular sides 7-10 times longer than eyes. Among the other species with short elytra and eyes, S. andersoni is also conspicuous by its large size. The similarly large S. admirabilis and S. curtulus can be separated by the absence of a sclerotised endophallus.
Description: Length 6.1 mm. Colouration: Black, legs and antennae dark brown. Head: 0.97 mm long, 0.74 mm wide; eyes extremely short; PS : E ratio 7.2; sides slightly curved; posterior angles combined with posterior margin semi-circular; interantennal furrows weak; setiferous punctation moderately deep and dense; on average, interstices between punctures 1-1.5 times as wide as diameter of punctures; surface without microsculpture; shiny. Antennae with first antennomere half-length of head; antennomeres 2 and 3 approximately twice as long as wide; combined half-length of first antennomere; antennomeres 4-10 wider than long and increasing in width; each twice as wide as long; antennomeres 4 to 11 pubescent. Pronotum: 1.11 mm long, 0.70 mm wide; widest at anterior third; anteriorly narrowed in smooth convex curve; in central third slightly narrowed; in posterior third nearly parallel; posterior angles obtuse; posterior margin slightly convex; setiferous punctation as deep and dense as on head except adjacent to impunctate midline with denser punctation; irregular line approximately with 20 punctures; surface without microsculpture; shiny. Elytra: 0.78 mm long, 0.84 mm wide; without humeral angles; sides divergent posteriad; posterior angles rectangular; posterior margin deeply retreated to suture; setiferous punctation less deep than on pronotum but on average slightly denser; surface with weak irregular ground sculpture; less shiny than head and pronotum. Abdomen with setiferous punctation as dense as on elytra but weaker; surface with transverse microsculpture; matt; posterior margin of male sternite VII straight; posterior margin of male tergite VII slightly convex. Aedeagus oval; egg-shaped; at base wider than at apex; anterior angles obtuse; cones extremely short; C : A ratio 0.1; sclerotized endophallus with several torsions; covered by short teeth except a more transparent part apically; parameres slender; 5 times as long as cones; apically with hook-like prominence; apex acute; at lower edge of prominence several spines.  Petén,16.44569), 400 m elev., sifted leaf litter tropical moist for., 27.5.2009, leg ? (KNHM); 1 female, Progresso, 20 km N Estanesa de la Virgen, 1800-1900 m elev., cloud forest litter, 8.6.1991, leg. R. Anderson #91-55 (KNHM).
Diagnosis: According to the colouration, punctation and glossy surface, S. ashei resembles S. aenescens. It is distinctly smaller than S. aenescens and the parameres are extremely slender compared to the triangular parameres of S. aenescens. The aedeagus of S. ashei resembles the aedeagus of S. alticola. In contrast to the short elytra and absence of hind wings in S. alticola, elytra are long and with hind wings in S. ashei. Description: Length: 5.1 mm. Colouration: Totally black; legs and antennae dark brown. Head: 0.82 mm long, 0.59 mm wide; eyes moderately large, PS : E ratio 3.1; postocular sides slightly curved; postocular margin combined with posterior angles convex with short straight centre; setiferous punctation moderately sparse and deep; on average, interstices between punctures 1.5 times as wide as diameter of punctures; anteriorly with narrow impunctate midline; surface without microsculpture; polished. Antennae with first antennomere slightly longer than half-length of head; second and third antennomere conical; combined half as long as first; following antennomeres wider than long and increasing in width; twice as wide as long; antennomeres 4-11 pubescent; Pronotum: 0.91 mm long, 0.58 mm wide; widest at anterior third; anteriorly narrowed in smooth curve; sides in posterior half nearly parallel; posterior angles obtuse; posterior margin convex; setiferous punctation still sparser than on head; on average interstices more than twice as wide as diameter of punctures; laterally much sparser than adjacent to midline; wide midline impunctate; adjacent to midline irregular band of dense punctures; surface without microsculpture; polished. Elytra: 0.81 mm long, 0.72 mm wide; humeral and posterior angles sub-rectangular; posterior margin slightly retreated to suture; setiferous punctation slightly denser than on head and pronotum; on average, interstices between punctures 1.5 times as wide as diameter of punctures; surface without microsculpture; shiny. Abdomen with moderately dense setiferous punctation; segments at base with transverse microsculpture; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergite VII straight. Metatibia with one subapical ctenidium. Aedeagus oval; C : A ratio 0.18; sclerotised endophallus covered by minute teeth; broad and straight in posterior half; at middle with one loop; inner lobe of parameres slender and nearly half as long as aedeagus; outer lobe broad plate; half as long as inner lobe; at inner edge of inner lobe with row of setae.

Diagnosis:
In the uniformly black colouration and the elytral length, S. beniensis resembles S. ashei, but the punctation on the head is distinctly sparser than in this species and total length is distinctly smaller. Moreover, in males the shape of sternite VII is different, the endophallus is broadly sclerotised and the parameres are broad and s-shaped and not as slender as in S. ashei.
Description: Length: 4.3 mm, Colouration: Totally black; legs and antennae light brown. Head: 0.71 mm long, 0.57 mm wide; eyes large; PS : E ratio 2.6; postocular sides divergent; posterior angles combined with posterior margin convex with short straight part in front of neck; with weak interantennal furrows; setiferous punctation sparse and moderately deep; on average interstices between punctures twice as wide as diameter of punctures; anteriorly with impunctate midline; surface without microsculpture; polished. Antennae with first antennomere longer than half-length of head; second and third antennomere longer than wide; combined as long as half-length of first antennomere; following antennomeres wider than long and increasing in width; twice as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.79 mm long, 0.48 mm wide; widest at anterior third; anteriorly narrowed in smooth curve; sides in posterior half nearly parallel; posterior angles combined with posterior margin convex; setiferous punctation sparse and moderately deep; on average, interstices between punctures more than twice as wide as diameter of punctures; wide midline impunctate; surface without microsculpture; polished. Elytra: 0.75 mm long, 0.70 mm wide; humeral and posterior angles sub-rectangular; sides nearly parallel; posterior margin slightly retreated to suture; setiferous punctation denser than on head and pronotum; on average, interstices between punctures as wide as diameter of punctures; surface with weak isodiametric microsculpture; shiny. Abdomen with still denser setiferous punctation than elytra; without microsculpture; posterior margin of male sternite VII convex; posterior margin of male tergite VII straight; Metatibia with one subapical ctenidium. Aedeagus oval; anteriorly obtusely angled; C : A ratio 0.25; sclerotised endophallus broad; with few large teeth and numerous minute teeth; parameres broad; s-shaped; without setae. Diagnosis: S. brevipennis belongs to the alticola-subgroup with short elytra and eyes. It is smaller than the similar S. alticola and S. breviusculus and can be identified only by dissection of the aedeagus. The cones at apical orifice of the aedeagus are longer than in S. alticola and S. breviusculus. In contrast to S. breviusculus, the parameres are bilobed as in S. alticola but the endophallus is slenderer than in S. alticola. Description: Length: 3.9 mm. Colouration: Dark brown; legs and antennae lighter brown. Head: 0.64 mm long, 0.48 mm wide; eyes short, PS : E ratio 5.4; sides nearly parallel; posterior angles combined with posterior margin semi-circular; interantennal furrows weak; setiferous punctation deep and moderately dense; on average, interstices as wide as diameter of punctures; close to impunctate midline partly denser; surface without microsculpture; shiny. Antennae with first antennomere distinctly longer than half-length of head; antennomeres 2 and 3 longer than wide; combined half as long as first antennomere; antennomeres 4-10 twice as wide as long and increasing in width; antennomeres 4-11 pubescent. Pronotum: 0.82 mm long, 0.54 mm wide; widest at middle; anteriad narrowed in convex curve; posteriad parallel; posterior angles obtuse; posterior margin slightly convex; setiferous punctation as dense and deep as on head; wide midline impunctate; surface without microsculpture; shiny. Elytra: 0.52 mm long, 0.58 mm wide; humeral angles absent; sides divergent posteriad; posterior margin deeply retreated to suture; setiferous punctation as dense and deep as on pronotum; surface without microsculpture; shiny. Abdomen with setiferous punctation as dense as on elytra but finer; at base of segments with transverse microsculpture; posterior margin of male sternite VII semi-circular; posterior margin of male tergite VII straight. Aedeagus oval with anterior angles sub-rectangular; C : A ratio 0.19; one fifth as long as total length of aedeagus; sclerotized endophallus with several torsions; partly transparent; partly covered by moderately long spines and lobes; parameres short; slightly longer than cones; divided into two lobes; outer lobe plate-like; inner lobe slender with five setae.

Etymology:
The species name is a combination of the Latin words brevis (meaning short) and pennis (meaning elytra) and refers to the short elytra. Diagnosis: Among the species with short elytra and eyes, S. breviusculus resembles S. brevipennis and S. alticola in size. It is slightly larger than S. brevipennis and shorter than S. alticola. It is separated from these species by the reddish colouration of the head and pronotum and the extremely short cones at the apical orifice of the aedeagus.
Description: Length: 4.3 mm. Colouration: Blackish; head and pronotum light reddish; legs and antennae yellowish. Head: 0.74 mm long, 0.54 mm wide; eyes short; not prominent; PS : E ratio 4.3; slightly divergent to posterior sub-rectangular angles; posterior margin nearly straight; without interantennal furrows; impunctate midline narrow; setiferous punctation moderately deep and dense; on average, interstices between punctures 1-1.5 times as wide as diameter of punctures; surface without microsculpture; shiny. Antennae with first antennomere slightly longer than half-length of head; antennomeres 2 and 3 longer than wide; conical; combined slightly shorter than first antennomere; antennomeres 4 to 10 wider than long; antennomere 4 approximately 1.5 times as wide as long; antennomere 10 about twice as wide as long; all antennomeres pubescent. Pronotum: 0.86 mm long, 0.55 mm wide; widest at anterior third; anteriorly narrowed in smooth convex curve; posteriorly nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation denser and deeper than on head; wide midline impunctate; irregular line adjacent to midline approximately with 17-18 punctures; surface without microsculpture; shiny. Elytra: 0.62 mm long, 0.64 mm wide; without humeral angles; sides posteriorly divergent; posterior angles sub-rectangular; posterior margin slightly retreated to suture; setiferous punctation as deep and dense as on pronotum; on average; interstices between punctures as wide as diameter of punctures; surface with weak irregular ground sculpture; less shiny than head and pronotum. Abdomen with setiferous punctation as dense as on elytra but weaker than on elytra; setae pointing posteriad; surface with weak transverse netlike microsculpture; matt; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergite VII straight. Aedeagus oval; without anterior angles; cones extremely short; C : A = 0.04; sclerotised endophallus in anterior half transparent; in posterior half densely covered by short teeth; with several torsions; parameres short and slender; not divided into two lobes; without sensillae or setae.

Diagnosis:
The species resembles S. aenescens in external appearance as it is a moderately large species with moderately small eyes. The aedeagus is unique among the known Somoleptus species by the small circular closure of the central lobe. Additionally, the parameres are extremely broad, forming a forceps-like structure.
Description: Length: 5.5 mm. Colouration: Black; legs and antennae dark brown. Head: 0.89 mm long, 0.69 mm wide; eyes moderately large, slightly prominent; PS : E ratio 3.3; posteriad, sides slightly divergent; posterior angles combined with posterior margin semi-circular; interantennal furrows weak; setiferous punctation irregular; on average, extremely sparse and moderately deep; on average, 2-3 times as long as diameter of punctures; on interocular space partly denser and with larger punctures; surface without microsculpture; polished. Antennae with first antennomere slightly longer than half-length of head; antennomeres 2 and 3 longer than wide; combined slightly shorter than half-length of first antennomere; antennomeres 4-10 wider than long and increasing in width; antennomere 4 nearly twice as wide as long, antennomere 10 nearly 3 times as long as wide; antennomeres 4-11 pubescent. Pronotum: 1.05 mm long, 0.62 mm wide; widest near middle; anteriad narrowed in long convex curve; posteriad slightly convergent; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation as deep as on head but slightly denser; on average, interstices between punctures 1.5-2 times as wide as diameter of punctures; wide midline impunctate; irregular line adjacent to midline with 10-14 punctures; surface without microsculpture; polished. Elytra: 0.88 mm long, 0.83 mm wide; humeral and posterior angels sub-rectangular; posteriad, sides slightly divergent; posterior margin slightly retreated to suture; setiferous punctation as deep and dense as on pronotum; along suture slightly deeper; surface without microsculpture; shiny. Abdomen with setiferous punctation as dense as on elytra but distinctly finer; surface without microsculpture; shiny; posterior margin of male sternite VII with semi-circular emargination at centre; posterior margin of male tergite VII straight. Aedeagus oval; egg-shaped; at base slightly wider than at apex; apical angles obtuse; ventral closure circular; apical orifice wide with cones retreated interiorly; C : A ratio 0.22; sclerotized endophallus with central torsion and covered by moderately large teeth; in apical straight part, teeth smaller; at apex nearly transparent; parameres long and thick; half as long as total length of central lobe; basic part straight; at apex shortly curved to inner side; forming a forceps; at base with numerous setae; apically with numerous sensillae.  Diagnosis: According to the shape of the elytra, S. brunneus resembles S. alticola. However, the elytra of S. alticola are still shorter and the colouration is much darker than in S. brunneus. Moreover, males are distinguished from S. alticola by the different shape of sternite VII and the endophallus. The parameres are similarly slender in both species, but the row of setae at the inner face is longer in S. brunneus than in S. alticola.

Etymology
Description: Length: 4.9 mm. Colouration: dark brown, legs and antennae light brown. Head: 0.84 mm long, 0.69 mm wide; eyes extremely small; PS : E ratio 5.0; postocular sides slightly divergent; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation dense and moderately deep; on average, interstices between punctures 1-1.5 times as wide as diameter of punctures; narrow midline impunctate; surface without microsculpture; polished. Antennae with first antennomere half-length of head; second and third antennomere longer than wide; conical; combined slightly shorter than half-length of first antennomere; third slightly shorter than second; following antennomeres twice as wide as long; increasing in width; antennomere 4-11 pubescent. Pronotum: 1.00 mm long, 0.62 mm wide; widest at anterior third; anteriad narrowed in smooth curve; sides posteriorly slightly convergent; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation finer and sparser than on head; wide midline impunctate; adjacent to midline with irregular row of 20 punctures; surface without microsculpture, polished. Elytra: 0.68 mm long, 0.72 mm wide; humeral angles nearly absent; sides posteriorly divergent to sub-rectangular posterior angles; posterior margin retreated to suture; setiferous punctation as dense and deep as on head; surface partly with irregular fine ground sculpture; less shiny than head and pronotum. Abdomen with similarly dense and deep setiferous punctation as elytra; surface with transversely reticulate microsculpture; slightly shiny; posterior margin of male sternite VII with weak triangular incision; posterior margin of male tergite VII slightly convex. Aedeagus oval; cones at apical orifice moderately long; C : A ratio 0.15; sclerotised endophallus in most parts broad and covered by minute teeth; at base with several large teeth; inner lobe of parameres slender; much longer than cones; at inner face with row of long setae; outer lobe short.
Diagnosis: Among the brown species of the genus, S. cavicola can be distinguished by the yellowish-brown humeral angles of the elytra. Furthermore, the aedeagus is characteristic by the small endophallus and the parameres, which are broad at base and narrowed to an acute apex.
Description: Length: 5.2 mm Colouration: Dark brown; base of elytra lighter, yellowish brown; legs and antennae yellow-brown. Head: 0.87 mm long, 0.68 mm wide; long-oval; posteriad, slightly divergent to nearly semi-circular posterior margin; eyes small; PS : E ratio 4.6; praeocular sides slightly emarginate to base of mandibles; interantennal furrows weak; reaching anterior third of eyes; umbilicate punctation weak and sparse; on average, interstices between punctures 10 times as wide as diameter of punctures; surface without microsculpture polished. Antennae geniculate; first antennomere slightly longer than half-length of head; second and third antennomere triangular and slightly longer than wide; following antennomeres wider than long and increasing in width; fourth antennomere nearly twice as wide as long; tenth antennomere 2.5 times as wide as long; all antennomeres with long setae; antennomeres 4-11 pubescent. Pronotum: 1.01 mm long, 0.63 mm wide; widest at anterior third; anteriad, convergent to neck in wide convex curve; posteriad, slightly convergent in central third, nearly parallel in posterior third; posterior margin straight; posterior angles shortly rounded; setiferous punctation distinctly denser and larger than on head; narrow midline impunctate; irregular line of punctures adjacent to midline with approximately 18 punctures; surface without microsculpture; polished. Elytra: 0.88 mm long, 0.79 mm wide: humeral angles nearly rectangular; sides posteriad nearly parallel; posterior angles nearly rectangular; posterior margin curved; posterior margin widely retreated to suture; setiferous punctation dense and moderately deep; on average; interstices between punctures as wide as diameter of punctures; surface with irregular coriaceous ground sculpture; less shiny than head and pronotum. Abdomen densely covered by setiferous punctation; setae pointing posteriad; surface with weak isodiametric microsculpture; male sternite VII and tergite VII simply rounded at posterior margin; posterior margin of male sternite VII slightly more prominent than that of tergite VII. Aedeagus round oval; cones at apical orifice short; C : A ratio 0.08; endophallus small; straight in anterior half; with loop in posterior half; teeth of endophallus small; in anterior half slightly larger than in posterior half; inner lobe of parameres long; nearly half as long as total length of aedeagus; triangular with acute apex; without setae, but numerous sensillae; outer lobe irregularly triangular and transparent.

Diagnosis:
The species is characterised by its small eyes, the absence of hind wings and humeral angles. In this respect it resembles S. agricola and S. brunneus. It is separated from S. agricola by the brown colouration and from S. brunneus from the larger eyes and the postocular parallel sides. Additionally, males can be easily distinguished from these two species by the long triangular tooth at posterior margin of male sternite VII and the long cones at the apical orifice of the aedeagus.
Description: Length: 4.1 mm. Colouration: Brown; pronotum and elytra lighter brown; elytra at base indistinctly darkened. Head: 0.73 mm long, 0.53 mm wide; eyes small; PS : E ratio 8.0; approximately parallel; posterior angles shortly rounded; posterior margin nearly straight; inter-antennal lines weak; setiferous punctation moderately dense and deep; on average, interstices between punctures slightly wider than diameter of punctures; without impunctate midline; only on clypeus a narrow central space impunctate; surface with extremely weak irregular microsculpture; shiny. Antennae geniculate; first antennomere slightly longer than length of head; second and third antennomere triangular; second antennomere 1.5 times as long as third; third antennomere as long as apical width; following antennomere thick; wider than long and increasing in width; fourth antennomere approximately twice as wide as long; tenth antennomere nearly 2.5 times as wide as long; antennomeres 4-11 pubescent; all antennomeres with setae. Pronotum: 0.91 mm long, 0.54 mm wide; widest at middle; anteriad convexly narrowed; posteriad, nearly parallel; posterior angles shortly rounded; posterior margin nearly straight; setiferous punctation as dense and deep as on head except wide impunctate midline; adjacent to midline with irregular line of 12-13 punctures; without microsculpture; shiny. Elytra: 0.64 mm long, 0.63 mm wide; humeral angles absent; sides posteriad divergent; posterior angles nearly rectangular; posterior margin v-shaped; umbilicate punctation dense and deep; denser than on head and pronotum; on average, interstices between punctures slightly shorter than diameter of punctures; surface with irregularly weak microsculpture; less shiny than head and pronotum. Abdomen with weaker and finer setiferous punctation than on forebody; transversely reticulate microsculpture deeper than on elytra; still less shiny; male sternite VII with long acute triangular process; male tergite VII at posterior margin straight. Aedeagus oval; anteriorly sub-rectangular; cones at apical orifice long; C : A ratio 0.45; endophallus slender; with one narrow loop in posterior half; covered by large lobes; lobes widest in central part; smaller in posterior part; parameres with slender inner lobe and outer lobe as large plate with concave inner side and rounded apex; inner lobe slightly curved; digit-like; covered with numerous sensillae; without setae; digit inserted at middle of outer edge of plate-like outer lobe. Diagnosis: Among the species with short elytra and absent humeral angles, S. curtipennis mostly resembles S. alticola from the same region by the extremely short elytra and the black colouration. The apical cones of the aedeagus are similarly short. In S. alticola the posterior margin of the elytra is more retreated to the suture than in S. curtipennis. The smaller endophallus of the aedeagus is covered by large spines in S. curtipennis; whereas it is broader and covered by minute teeth in S. alticola.
Description: Length: 5.2 mm. Colouration: Black, legs light brown; antennae slightly darker brown. Head: 0.85 mm long, 0.65 mm wide; eyes short; PS : E ratio 7.9; postocular sides divergent; posterior angles combined with posterior margin approximately semi-circular; setiferous punctation moderately deep and dense; on average, interstices between punctures as wide as diameter of punctures; on posterior vertex interstices slightly wider; between eyes with small impunctate area; surface with extremely weak isodiametric microsculpture; moderately shiny. Antennae with first antennomere half-length of head; second and third antennomere longer than wide; conical; combined half-length of first antennomere; following antennomeres wider than long and increasing in width; 1.5 times as wide as long; antennomeres 4-11 pubescent. Pronotum: 1.08 mm long, 0.71 mm wide; widest at anterior third; anteriad, sides convergent to neck; posteriad approximately parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation as dense and deep as on head; wide midline impunctate; surface without microsculpture; polished. Elytra: 0.71 mm long, 0.80 mm wide; humeral angles absent; sides slightly divergent; posterior angles rectangular; posterior margin retreated to suture; setiferous punctation much denser than on head and pronotum; on average, interstices between punctures half as wide as diameter of punctures; surface with extremely weak microsculpture; moderately matt. Abdomen with finer setiferous punctation than on fore-body, as dense as on pronotum; posterior margin of sternite and tergite VII of male centrally prominent. Aedeagus oval; cones at apical orifice short; C : A ratio 0.07; sclerotised endophallus elongate with torsions and long spines; parameres slender; nearly half as long as total length of central lobe; at inner edge with row of paired setae.

Etymology:
The species name is a combination of the Latin words curtus (meaning short) and pennis (meaning elytra) and refers to the short elytra of the species.

Diagnosis:
The species is conspicuous among the species with short elytra by the large size. Moreover, the structure of the aedeagus is specific by the absence of a sclerotised endophallus. It can be separated from the similar S. admirabilis only by the aedeagus. Compared to S. admirabilis, the aedeagus of S. curtulus is smaller and the apical orifice with cones is retreated.
Description: Length: 6.2 mm. Colouration: Black; legs and antennae light brown. Head: 0.89 mm long, 0.77 mm wide; eyes moderately short; PS: E ratio 5.4; slightly divergent; posterior angles combined with posterior margin nearly semicircular; except short straight part in front of neck; setiferous punctation deep and dense; on average, interstices between punctures as wide as or slightly shorter than diameter of punctures; vertex with narrow impunctate midline; on anterior head with wider impunctate midline; at posterior head with contiguous punctation; surface without microsculpture; shiny. Antennae with first antennomere distinctly longer than half-length of head; second and third antennomere conical; combined half as long as first antennomere; following antennomeres wider than long; fourth antennomere slightly wider than long; tenth antennomere nearly twice as wide as long; antennomeres 4-11 pubescent. Pronotum: 1.18 mm long, 0.72 mm wide; parallel; widest at anterior fifth; shortly narrowed in convex curve; posteriad continuously narrowed to sub-rectangular hind angles; posterior margin slightly convex; setiferous punctation deep and dense, but slightly less dense than on head; on average, interstices between punctures as wide as or slightly wider than diameter of punctures; wide midline impunctate; Elytra: 0.71 mm long, 0.82 mm wide; without humeral angles; sides slightly divergent to posterior subrectangular angles; without hindwings; posterior margin triangularly retreated to suture; setiferous punctation still denser than on head; interstices between punctures distinctly shorter than diameter of punctures; partly coriaceous; surface with irregular ground sculpture; partly with micro-punctation; matt. Abdomen with setiferous punctation as dense as on elytra, but less deep; surface with isodiametric microsculpture; matt; posterior margin of male sternite VII with deep triangular incision; posterior margin of male tergite VII straight. Aedeagus nearly circular; without sclerotised endophallus; cones at large orifice in relation to aedeagus large; C : A ratio 0.25; parameres as long as two third of total length of aedeagus; hook-like with curved apical part; not divided in inner and outer lobe; few short setae at inner face; few setae on shaft.

Etymology:
The species name is the diminutive of the Latin word curtus (meaning short) and refers to the short elytra.
Somoleptus elongatulus spec. nov. Diagnosis: Among the similarly large species of approximately 6 mm length, the elytra of S. elongatulus are longer than wide. Additionally, the black colouration is characteristic for the species. Males can be easily identified by the specific structure of the aedeagus with the triangular cones at apical orifice placed on short styli.
Description: Length: 6.01 mm. Colouration: Black; legs and antennae dark brown. Head: 0.94 mm long, 0.72 mm wide; eyes moderately small; PS : E ratio 4.1; parallel; posterior angles combined with posterior margin nearly semi-circular; setiferous punctation irregularly sparse and moderately deep; on average, interstices between punctures 1.5 to 2 times as wide as diameter of punctures; without traces of impunctate midline; surface without microsculpture; polished. Antennae with first antennomere distinctly longer than half-length of head; second and third antennomere each twice as long as wide; combined as long as first antennomere; following antennomeres wider than long and increasing in width; fourth twice as wide as long; tenth 2.2 times as wide as long; antennomere 4-11 pubescent. Pronotum: 1.18 mm long, 0.74 mm wide; widest at anterior third; narrowed anteriad in smooth convex curve; posteriad nearly parallel; posterior angles subrectangular; posterior margin slightly convex; setiferous punctation similarly dense and deep as on head, but with moderately wide midline impunctate; surface without microsculpture; polished. Elytra: 1.04 mm long, 0.98 mm wide; humeral and posterior angles subrectangular; sides posteriad slightly divergent; posterior margin slightly retreated to suture; setiferous punctation distinctly denser than on head and pronotum; on average, interstices between punctures as wide as diameter of punctures or slightly shorter; surface without microsculpture, but less polished than pronotum. Abdomen with still denser setiferous punctation than elytra; setiferous punctation partly coriaceous; posterior margin of male sternite and tergite VII straight. Metatibia with four subapical ctenidia. Aedeagus oval; cones short; C : A ratio 0.22; placed on short styli in short distance from the apical orifice; distinctly triangular; sclerotised endophallus with two torsions and irregular teeth; at basal end with long spine; parameres broad; shape spoonlike; at apex acute; at base narrower than at middle; at outer edge with numerous cannulate sensillae; on inner edge at apex with one seta.

Etymology:
The species name is the diminutive of the Latin word elongatus which, among others, means distant from and refers to the specific structures of the apical cones of the aedeagus, which are shortly away from the apical orifice. Diagnosis: Somoleptus gigas is the largest known species of the genus. With 6.6 mm length it is even larger than S. maximus. In contrast to S. maximus, the head is very densely punctate and the shape is more triangular; wider at posterior angles than at front. In S. maximus, the punctation is finer and the shape of head is oval without posterior angles. Moreover, the pronotum is narrowed in central half, whereas it is nearly parallel in S. gigas.
Description: Length: 6.6 mm. Colouration: Black, legs and antennae dark brown. Head: 1.16 mm long, 0.91 mm wide; eyes moderately long; PS : E ratio 2.4; postocular sides slightly divergent posteriad; posterior angles combined with posterior margin nearly semi-circular; setiferous punctation extremely dense and deep; partly coriaceous; between eyes with irregularly wide impunctate midline; surface without microsculpture; shiny. Antennae with first antennomere slightly longer than half-length of head; second and third antennomere longer than wide; conical; combined as long as half-length of first antennomere; following antennomeres wider than long; increasing in width; approximately twice as wide as long; all antennomeres pubescent. Pronotum: 1.31 mm long, 0.81 mm wide; widest at anterior third; convergent to neck in smooth curve; sides posteriorly nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation sparser than on head; wide midline impunctate; surface without microsculpture; polished. Elytra: 1.31 mm long, 1.19 mm wide; humeral and posterior angles sub-rectangular; sides slightly divergent posteriad; posterior margin triangularly retreated to suture; setiferous punctation deep and dense; on average, interstices between punctures as wide as diameter of punctures; surface without microsculpture; shiny. Abdomen with setiferous punctation as dense but less deep than on elytra; setae long; pointing posteriad; surface without microsculpture; moderately shiny; posterior margin of male sternite VII slightly emarginate; posterior margin of male tergite VII slightly prominent (similar as in Fig. 44c, d). Aedeagus oval with sub-rectangular anterior angles; cones at apical orifice long; C : A ratio 0.28; sclerotised endophallus with torsion in longitudinal direction; covered by lobes; parameres divided into two lobes; outer lobe plane; approximately half as long as inner lobe; inner lobe triangular; only slightly longer than cones; at inner edge with row of paired long setae.

Etymology:
The species name is derived from the Greek word gigas meaning huge and refers to the large size of the species.
Somoleptus grandiconus spec. nov. Antennae with first antennomere slightly longer than half-length of head; antennomeres 2 and 3 longer than wide; combined slightly longer than half-length of first antennomere; antennomeres 4-10 wider than long and approximately 1.5 times as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.88 mm wide, 0.54 mm wide; widest shortly behind anterior third; anteriad convergent to neck; posteriad nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation similarly deep and dense as on head; wide midline impunctate; irregular row of punctures adjacent to midline with approximately 15 punctures; surface without microsculpture; shiny. Elytra: 0.70 mm long, 0.63 mm wide; humeral and posterior angles subrectangular; sides approximately parallel; posterior margin slightly retreated to suture; setiferous punctation as deep as on head and pronotum but distinctly denser; on average, interstices between punctures as wide as diameter of punctures; surface with weak isodiametric microsculpture; matt. Abdomen with setiferous punctation as dense as on elytra but weaker; setae pointing posteriad; at base of segments with netlike microsculpture; at apex of segments microsculpture isodiametric and extremely fine; shiny; posterior margin of male sternite VII broadly prominent; posterior margin of male tergite VII with short semi-circular prominence as in Fig. 31c, d). Aedeagus oval with sub-rectangular anterior angles; cones at apical orifice extremely large and broad; C : A ratio 0.60; endophallus slightly curved; broad; covered by teeth; teeth at apex longer than at base; parameres divided into plate-like outer lobe and slender inner lobe; nearly as long as total aedeagus; inner lobe with row of setae at inner edge and several sensillae.

Etymology:
The species name is a combination of the Latin words grandis (meaning large) and conus referring to the large cones at the apical orifice of the aedeagus. posterior angles combined with posterior margin nearly semi-circular; interantennal furrows distinct; setiferous punctation deep; irregularly dense; on average, interstice between punctures as wide as diameter of punctures; on posterior vertex interstices slightly wider; between eyes much closer; narrow midline impunctate; surface without microsculpture; shiny. Antennae with first antennomere longer than half-length of head; second and third antennomere longer than wide; combined longer than half-length of first antennomere; antennomeres 4 to 10 wider than long and slightly increasing in width; fourth twice as wide as long; tenth 1.5 times as wide as long; antennomeres 4 to 11 pubescent. Pronotum: 0.86 mm long, 0.49 mm wide; widest at anterior third; sides anteriad convergent to neck; in posterior half nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; slightly weaker than on head; as dense as on posterior vertex; wide midline impunctate; irregular row of punctures adjacent to midline with approximately 16 punctures; surface without microsculpture; shiny. Elytra: 0.98 mm long, 0.82 mm wide; humeral angles sub-rectangular; sides posteriorly slightly divergent; posterior angles smooth; posterior margin largely convex; deeply retreated to suture; setiferous punctation as deep and dense as on pronotum; surface wth weak isodiametric microsculpture; slightly less shiny than pronotum. Abdomen with finer setiferous punctation than forebody; microsculpture at base of segments transversely reticulate; segments apically without microsculpture; shiny; posterior margin of male sternite VII convexly rounded; posterior margin of male tergite VII straight (similar as in Fig. 21c, d). Aedeagus oval; widest near base; anterior angles nearly absent; cones moderately long; C : A ratio 0.21; endophallus with two torsions; weakly sclerotised; partly transparent; with short teeth; basically, with few thicker teeth; parameres longer than half-length of central lobe; divided into two lobes; outer lobe circular plate; inner lobe slender; elongate; along at inner edge with row of numerous setae.

Etymology:
The species name is derived from the Latin noun humus (meaning soil or decomposing organic litter) and the verb colere (meaning inhabiting) and refers to the habitat of the species, the litter layer of deciduous woods. 0.66 mm long, 0.70 mm wide; without humeral angles; sides slightly divergent posteriad; posterior angles obtuse; posterior margin convexly curved; deeply retreated to suture; setiferous punctation deeper and denser than on pronotum; on average, interstices between punctures less wide than diameter of punctures; surface with weak isodiametric microsculpture; less shiny than pronotum. Abdomen with setiferous punctation as dense as on elytra but much finer; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergite VII straight (similar as in Fig. 21a, d). Aedeagus oval; cones at apical orifice long and relatively slender; C : A ratio 0.33; sclerotised endophallus partly transparent with scattered teeth; partly with thick lobes; parameres one third longer than cones; divided into two lobes; outer lobe circular with row of short spines; inner lobe slender with row of long setae in apical half.

Etymology:
The species name is derived from the Latin words longus (meaning long) and -ceps (short form of caput, meaning head).

Remarks:
The species was sufficiently described by Smetana (1982), according to whom it is widely distributed in eastern USA up to the Canadian border. The concentration of records in north-eastern USA may be due to higher collection intensity compared to southern USA. The new records from Mexico and Honduras show that the species also occurs in high mountain sites under a generally warmer climate. The study of the parameres of the aedeagus exhibit that the species has a bilobed paramere with slender inner and plate-like outer lobe. The outer lobe is approximately half as long as the slender inner lobe. The slender inner lobe has 6 setae partly arranged in pairs. nearly twice as long as wide; following antennomeres wider than long and increasing in width; fourth antennomere 1.3 times as wide as long; tenth antennomere twice as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.63 mm long, 0.40 mm wide; widest in anterior third; anteriad, conically narrowed to neck; posteriad, slightly narrowed in central third and even less narrowed in posterior third; setiferous punctation as weak and sparse as on head; wide midline impunctate; irregular line of punctures adjacent to midline with 13 to 15 punctures; surface without microsculpture; shiny. Elytra: 0.54 mm long, 0.54 mm wide; humeral angles obtuse; sides distinctly divergent; posterior angles shortly rounded; nearly rectangular; posterior margin approximately straight with short incision at suture; setiferous punctation much denser and slightly deeper than on pronotum; surface with weak isodiametric microsculpture; less shiny than pronotum. Abdomen with setiferous punctation as deep as on elytra but still denser; surface without microsculpture; shiny; male sternite VII with straight posterior margin and short central incision; male tergite VII straight. Mesotibia with three, metatibia with two subapical ctenidia. Aedeagus oval; at apex indistinctly rectangular with emargination at base of parameres on each side of central orifice; cones at apical orifice short; C : A ratio 0.08; endophallus with apical knot and posterior wide stripe densely covered by minute teeth; stripe posteriorly folded; parameres elongate; bilobed; outer lobe nearly as long and wide as inner lobe; inner lobe curved; with numerous short and fine setae at inner face; setae at base distinctly longer than at apex. Antennae with first antennomere distinctly longer than half-length of head; second and third antennomere longer than wide and equal in length; combined slightly shorter than half length of first antennomere; following antennomeres twice as wide as long; increasing in width; antennomeres 4-11 pubescent. Pronotum: 1.04 mm long, 0.60 mm wide; widest at anterior third; anteriad narrowed to neck in smooth convex curve; posterior half nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation as deep and dense as on head; moderately wide midline impunctate; surface without microsculpture; polished. Elytra: 0.98 mm long, 0.90 mm wide; humeral and posterior angles sub-rectangular; sides divergent to posterior margin; posterior margin triangularly retreated to suture; setiferous punctation much deeper and denser than on head and pronotum; on average, interstices between punctures shorter than diameter of punctures; surface without microsculpture; shiny. Abdomen with setiferous punctation as dense as on elytra, but much finer; surface without microsculpture; shiny; posterior margin of male sternite and tergite VII straight (similar as in Fig. 22c, d).
Aedeagus long oval with anterior angles sub-rectangular; cones at apical orifice short; C : A ratio 0.16; sclerotised endophallus small; parameres elongate; curved in apical third; not divided into inner and outer lobe.  Berlese, 9.6.1987, leg. R. Anderson;2 females, Oaxaca, 40 km SW Valle Nacional, km 93, 1900m elev., oak forest leaf litter, Berlese, 26.7.1992 Head: 0.67 mm long, 0.56 mm wide; eyes moderately large; PS : E ratio 4.2; postocular sides divergent to posterior sub-rectangular angles; posterior margin approximately straight; setiferous punctation deep and dense; on average, interstices between punctures less wide than diameter of punctures; on anterior vertex denser than on posterior vertex; narrow midline impunctate; surface without microsculpture; polished. Antennae with first antennomere slightly longer than half-length of head; second and third antennomere 1.5 times longer than wide; combined slightly shorter than half-length of first antennomere; following antennomeres wider than long; fourth antennomere nearly twice times as long as wide; tenth slightly more than twice times as long as wide; antennomeres 4-11 pubescent. Pronotum: 0.82 mm long, 0.54 mm wide; widest at anterior third; anteriad, continuously convergent to neck; posteriad, slightly convergent to sub-rectangular posterior angles; posterior margin slightly convex; setiferous punctation sparser and less deep than on head; on average, interstices between punctures twice as wide as diameter of punctures; wide midline impunctate; adjacent to midline with irregular row of punctures; interstices between punctures less wide than laterally; surface without microsculpture; polished. Elytra: 0.64 mm long, 0.59 mm wide; humeral and posterior angles sub-rectangular; sides posteriad slightly divergent; posterior margin slightly retreated to suture; setiferous punctation as dense and deep as on vertex; on average, interstices between punctures as wide as diameter of punctures; surface without microsculpture; shiny; Abdomen with setiferous punctation slightly denser than on elytra, but finer; setae pointing posteriad; at base of segments with deep transversely reticulate microsculpture; apical part of segments without microsculpture; moderately shiny; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergite VII straight (similar as in Fig. 21 c, d). Aedeagus oval with anterior angles sub-rectangular; cones at apical orifice moderately large; C : A ratio 0.31; sclerotised endophallus narrow, u-shaped; parameres divided in slender inner lobe and plate-like outer lobe; inner lobe with row of setae on inner face.

Somoleptus montanus
Diagnosis: Among the large species of more than 6.0 mm length with quadrate elytra, S. montanus can be distinguished from the similar S. strigulata by the small eyes. The similar species S. strigulata is known only from the island of Hispaniola and has still smaller eyes. Among the laevis-group, S. montanus is characterised by the broad uni-lobed parameres with central swelling.
Description: Length: 6.2 mm. Colouration: Black; legs and antennae light brown. Head: 0.97 mm long, 0.81 mm wide; eyes small; not prominent; P : E ratio 5.9; postocular sides nearly parallel; posterior angles combined with posterior margin semi-circular; interantennal furrows weak; setiferous punctation moderately dense and deep; on average, interstices between punctures as wide as or slightly wider than diameter of punctures; without impunctate midline; on clypeus with small impunctate spot; surface with extreme weak isodiametric microsculpture; shiny. Antennae with first antennomere half-length of head; second and third antennomere longer than wide; combined half-length of first antennomere; antennomeres 4 to 10 wider than long; increasing in width; fourth antennomere twice as wide as long; tenth antennomere slightly wide than twice as wide as long; antennomeres 4-11 pubescent. Pronotum: 1.19 mm long, 0.77 mm wide; widest in anterior third; anteriad, narrowed in smooth convex curve; in posterior half nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; moderately wide midline impunctate; setiferous punctation denser and deeper than on head; on average, interstices between punctures as wide as diameter of punctures; partly slightly shorter; irregular line of punctures adjacent to midline with approximately 20 punctures; without microsculpture; polished. Elytra: 0.86 mm long, 0.87 mm wide; without humeral angles; sides posteriorly divergent; posterior angles sub-rectangular; posterior margin triangularly retreated to suture; setiferous punctation deep and dense; on average, interstice between punctures half as wide as diameter of punctures; surface with irregular ground-sculpture; matt. Abdomen with dense and weak setiferous punctation; surface with transverse reticulate microsculpture; slightly shiny; male sternite and tergite VII with straight posterior margin. Aedeagus oval with anterior angles sub-rectangular; cones partly inside apical orifice; moderately long; C : A ratio 0.21; sclerotised endophallus with two torsions; at base covered by minute teeth; apically with larger lobes; parameres broad; broadest in central part; apically narrowed to acute apex; with two spots of sensillae; on at apex; second in central part.

Etymology:
The species name is derived from the same Latin word (meaning montane) and refers to the high elevation, where it was collected in Venezuela.

Diagnosis:
Unfortunately, only the male type specimen was in the collections examined.
Description: Length: 4.0 mm. Colouration: Dark brown; anterior half of pronotum slightly lighter, posterior angles of elytra still lighter; nearly yellow. Head: 0.72 mm long, 0.54 mm wide: eyes large; slightly prominent; postocular sides nearly parallel; PS : E ratio 2.4; posterior angles widely rounded; combined with posterior margin nearly semi-circular; interantennal space at anterior margin extremely short; divided by triangular process; on both sides of process with deep groove; setiferous punctation sparse and moderately weak; interstices between punctures three to four times as wide as diameter of punctures; surface without microsculpture; polished. Antennae with first antennomere two third of head length; antennomere two and three conical; as long as their apical width; following antennomeres much wider than long; antennomere four nearly twice as wide as long; antennomere ten three times as wide as long; all antennomeres pubescent. Pronotum: 0.86 mm long, 0.50 mm wide; widest slightly behind anterior third; conically narrowed to neck; approximately parallel in posterior third; posterior angles widely rounded; combined with posterior margin nearly semi-circular; setiferous punctation moderately deep and sparse; adjacent to impunctate midline with irregular line of 16-17 punctures; surface without microsculpture; polished. Elytra: 0.83 mm long, 0.77 wide; humeral angles approximately rectangular; sides slightly divergent to rectangular posterior angles; posterior margin slightly convexly curved with incision at suture; setiferous punctation deeper and larger than on head and pronotum; interstices between punctures approximately as wide as diameter of punctures; surface without microsculpture; polished. Abdomen with setiferous punctation as dense as on elytra but much finer; weak microsculpture transversely reticulate; surface shiny; male sternite VII deeply emarginate; on the inner edge of emargination with longitudinal process; male sternite VII straight; only with slight central projection. Aedeagus long oval; pair of cones at inner side of apical orifice; weak and with fine spines or hairs; C : A ratio 0.17; parameres broad and long; two third as long as central lobe; curved; in ventral view, shape like a forceps; short apical part parallel; in lateral view shape more triangular; in central part with numerous sensillae. Sharp, 1885 Figs 36a, b;47 D Somoleptus obscurus Sharp, 1885: 496 Type material examined: female, holotype: Panama: Peña Blanca, 3000-4000 ft. elev., leg. Champion (BMNH).

Diagnosis:
Unfortunately, the single type specimen is a female. Males were only found among the specimens from Venezuela. Thus, a clear differentiation from the similar S. obsoletus, S. sparsus and S. pecki is difficult. It seems that S. obscurus is larger in size and the elytra are shorter than in the three similar species. It can be distinguished from S. obsoletus by the distinct sub-rectangular angles of the head and from S. pecki by the larger eyes. In contrast to S. sparsus, the punctation of the head is much denser. Whereas interstices between punctures in S. obscurus are as wide as diameter of punctures, interstices between punctures in S. sparsus are nearly twice as wide as diameter of punctures. The aedeagi of all four species are very similar. Parameres are straight in S. obscurus and S. pecki, but curved in S. obsoletus and S. sparsus. Description: Length: 4.4 mm. Colouration: Blackish; legs and antennae light brown. Head: 0.69 mm long, 0.52 mm wide; eyes large; PS : E ratio 2.4; postocular sides nearly parallel; posterior angles combined with posterior margin nearly semi-circular; setiferous punctation deep and dense; on average, interstices as wide as diameter of punctures; moderately narrow; impunctate midline on posterior vertex absent; surface without microsculpture; polished. Antennae with first antennomere slightly shorter than half-length of head; antennomeres 2-3 longer than wide; combined slightly shorter than half-length of first antennomere; antennomeres 4-10 wider than long and increasing in width; antennomere 4, 1.5 times wider than long; antennomere 10 twice as wide as long; antennomere 4-11 pubescent. Pronotum: 0.76 mm long, 0.49 mm wide; widest shortly in front of middle; anteriad, continuously narrowed to neck in smooth convex curve; posteriad nearly parallel; posterior angles subrectangular; posterior margin slightly convex; setiferous punctation as dense and deep as on head; wide midline impunctate; surface without microsculpture; polished. Elytra: 0.79 mm long, 0.68 mm wide; humeral and posterior angles sub-rectangular; sides nearly parallel; posterior margin slightly convex; shortly retreated at suture; setiferous punctation as dense and deep as on head and pronotum; surface without microsculpture; shiny. Abdomen with setiferous punctation much denser, but finer than on elytra; setae pointing posteriad; posterior margin of male sternite VII with triangular process (as in Fig. 21c, d); posterior margin of male tergite VII straight. Metatibia with two subapical ctenidia. Aedeagus oval with sub-rectangular anterior angles; cones at apical orifice moderately short; C : A ratio 0.19; parameres divided into two lobes; a plate-like outer lobe and a straight slender inner lobe; approximately half as long as total length of aedeagus; both lobes nearly equal in length; inner lobe with row of partly long setae at inner face. Sharp, 1885 Figs 28a, b;47 E Somoleptus obsoletus Sharp, 1885: 496 Type material examined: male, holotype; Guatemala: near the city, Aceituno, leg. Champion (BMNH).

Somoleptus obsoletus
Additional material examined: Mexico: 1 female, San Luis Potosi, 11 mi W El Naranjo, 3200 ft elev., litter Liquidambar hollow trunk, 25.6.1973, leg. A. Newton (FMNH); 1 female, same region, 14 mi W Xilitla, 4800 ft elev., on fungi, 20-28.6.1971, leg. A. Newton (FMNH); 1 male, Oaxaca, 6 mi S Valle Nacional, 2000 ft elev., leaf litter, 19.5.1971, leg. S. Peck (FMNH); 1 male, Chiapas, 9.7 mi S Solusuchiapa, Hwy. 195, 530 m elv., montane tropical litter along stream, sifting, 5.5.1977, leg. J.S. Ashe (FMNH); 2 males, 10 km W El Bosque, 1475 m elev., pine/ cloud forest litter, 15.9.1992 The species closely resembles S. obscurus in dense punctation and sexual characters. It can be separated from that species by the smaller size (3.8 mm), surface covered by weak microsculpture, elytra having a yellow apical margin. At the aedeagus, the outer lobe of the parameres seems to be slightly shorter than in S. obscurus and with fewer setae at inner edge of the slender inner lobe. Description: Length: 3.8 mm. Colouration: Blackish brown; posterior margin of elytra yellowish; legs and antennae yellow. Head: 0.65 mm long, 0.49 mm wide; eyes large, PS : E ratio 2.9; postocular sides slightly curved; postocular angles combined with posterior margin nearly semi-circular; setiferous punctation deep and dense; on average, interstices between punctures as wide as diameter of punctures; moderately narrow impunctate midline absent on posterior vertex; surface partly with micro-punctation; moderately shiny. Antennae with first antennomere as long as half-length of head; second and third antennomere longer than wide; third slightly shorter than second; combined slightly longer than half-length of first antennomere; following antennomeres wider than long and increasing in width; fourth antennomere twice as wide as long; tenth 2.5 times as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.80 mm long, 0.48 mm wide; widest distinctly behind anterior third; anteriad, convergent to neck; posteriad, nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation as dense and deep as on head; wide midline impunctate; surface with weak isodiametric microsculpture; moderately shiny. Elytra: 0.79 mm long, 0.67 mm wide; humeral and posterior angles sub-rectangular; sides approximately parallel; posterior margin convex; deeply retreated to suture; setiferous punctation as dense and deep as on pronotum; surface with weak isodiametric microsculpture; moderately shiny. Abdomen with setiferous punctation as dense and deep as on elytra; setae pointing posteriad; surface with distinct transversely reticulate microsculpture; moderately matt; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergites VII straight (as in Fig. 21c, d). Metatibia with two subapical ctenidia. Aedeagus oval with sub-rectangular anterior angles; C : A ratio 0.25; sclerotised endophallus narrow; covered by minute teeth; in basal half with two torsions; in apical half straight; parameres divided in slender inner lobe and broad outer lobe; inner lobe with row of five setae at inner face.

Diagnosis:
The species is unique within the genus by the characteristic shape of the head with convergent postocular sides. The large cones of the aedeagus resemble those of S. grandiconus but the shape of the head is totally different between these two species. The aedeagus also resembles that of S. melanarius, but S. melanarius is much longer with 5.0-5.4 mm.
Description: Length: 3.7 mm. Colouration: Blackish to dark brown; abdomen slightly lighter brown; legs and antennae light brown. Head: 0.63 mm long, 0.48 mm wide; eyes large, prominent; PS : E = 1.7; postocular sides convergent to sub-rectangular posterior angles; interantennal furrows irregular; weak; setiferous punctation deep and moderately dense; on average, interstices between punctures as wide as diameter of punctures; impunctate midline indistinct; partly absent; surface without microsculpture; shiny. Antennae with first antennomere distinctly longer than half-length of head; antennomeres 2 and 3 longer than wide; combined half as long as first antennomere; antennomers 4-10 wider than long; increasing in width; approximately twice as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.75 mm long, 0.43 mm wide; widest slightly in front of anterior third; anteriad, conically narrowed to neck; posteriad, nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation dense but weak; irregular line of punctures adjacent to wide impunctate midline with 15 to 16 punctures; surface without microsculpture; shiny. Elytra: 0.80 mm long, 0.69 mm wide; humeral and posterior angles sub-rectangular; sides slightly divergent posteriad; posterior margin convexly curved; deeply retreated to suture; setiferous punctation dense and moderately deep; on average, interstices between punctures slightly shorter than diameter of punctures; surface with weak microsculpture; less shiny than head and pronotum. Abdomen with setiferous microsculpture weaker but as dense as on elytra; surface with weak netlike microsculpture; shiny; posterior margin of male sternite VII convexly rounded; posterior margin of male tergite VII with weak emargination (similar as in Fig. 31c, d). Aedeagus oval with sub-rectangular anterior angles; cones large; C : A = 0.41; endophallus transparent; weakly covered by short teeth; with few torsions; parameres twice as long as cones; divided into two lobes; outer lobe broad; as long as cones; inner lobe slender; slightly longer than outer lobe; in apical half with row of 5 paired setae.

Etymology:
The species name is derived from the Latin word oculus (meaning eye) and refers to the large prominent eyes of the species. Head: 0.89 mm long, 0.68 mm wide; eyes short; PS : E ratio 6.6; postocular sides convexly curved; posterior angles combined with posterior margin semi-circular; interantennal furrows absent; setiferous punctation deep and moderately dense; on average, interstices between punctures as wide as diameter of punctures; on posterior vertex partly denser; between eyes with impunctate midline; surface without microsculpture; shiny. Antennae with first antennomere slightly longer than half-length of head; antennomere 2 and 3 longer than wide; combined half-length of first antennomere; antennomeres 4 to 10 wider than long and increasing in width; fourth antennomere 1.5 times as wide as long; tenth antennomere twice as wide as long; antennomeres 4-11 pubescent. Pronotum: 1.09 mm long, 0.66 mm wide; widest at anterior third; anteriad narrowed to neck in smooth convex curve; posteriad nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex with straight centre; setiferous punctation as deep and dense as on head but with wide impunctate midline; irregular line adjacent to midline with 22 to 23 punctures; surface without microsculpture; shiny. Elytra: 0.67 mm long, 0.73 mm wide; without humeral angles; posterior angles rectangular; posterior margin deeply retreated to suture; setiferous punctation as deep and dense as on pronotum; surface with isodiametric ground-sculpture; less shiny than head and pronotum. Abdomen with similar setiferous punctation as on elytra but deeper microsculpture; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergite VII slightly convex (similar as in Fig. 21c, d). Aedeagus oval with sub-rectangular anterior angles; cones at apical orifice slightly curved; C : A ratio 0.22; sclerotised endophallus with basal torsion; partly transparent with sparse minute teeth, partly with thick dark lobes; parameres bilobed in plate-like outer lobe and slender inner lobe; outer lobe with few long setae at outer edge; inner lobe with numerous short and fine setae.

Etymology:
The species name derived from the Latin word ovalis meaning oval and refers to the oval shape of the head. Diagnosis: Unfortunately, the single type specimen is a female. As no other specimen was clearly identified as S. pallipes, the differentiation from the similar S. obscurus and S. obsoletus is unclear. However, the species can be identified by the long hind legs with extremely long metatarsi.

Somoleptus pallipes Sharp, 1885
Description: Length: 4.6 mm; Colouration: Black, legs and antennae yellow. Head: 0.75 mm long, 0.59 mm wide; eyes moderately small; PS : E ratio 4.3; postocular sides slightly divergent posteriad; posterior angles combined with posterior margin semi-circular; setiferous punctation deep and dense; on average interstices between punctures as wide as diameter of punctures; narrow midline impunctate; on posterior vertex midline absent; surface without microsculpture; polished. Antennae with first antennomere slightly longer than half-length of head; antennomere 2 and 3 longer than wide; equal in length; 1.5 times as long as wide; combined as long as half-length of first antennomere; following antennomeres wider than long and increasing in width; twice as wide as long; all antennomeres pubescent. Pronotum: 0.85 mm long, 0.51 mm wide; widest shortly in front of middle; anteriad, continuously convergent to neck; posteriad, approximately parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation as dense and deep as on head; wide midline impunctate; surface without microsculpture; polished; Elytra: 0.86 mm long, 0.71 mm wide; humeral and posterior angles sub-rectangular; sides approximately parallel; posterior margin triangularly retreated to suture; setiferous punctation as deep as on head, but much denser; on average, interstices between punctures half as wide as diameter of punctures; surface partly with isodiametric microsculpture; moderately matt. Abdomen with setiferous punctation finer than on fore-body but similarly dense; surface at base of segments with transverse microsculpture; apically without microsculpture; shiny. Metatibia with three subapical ctenidia; metatarsi combined nearly as long as metatibia. Sharp, 1885 Figs 26a, b;47 G Somoleptus parvulus Sharp, 1885: 496 Type material examined: 2 females, syntypes: Guatemala: Vera Paz, San Geronimo, leg. Champion; Panama, Los Remedios, leg. Champion (BMNH).
Diagnosis: The species extremely resembles S. struyvei in size, punctation and structure of the aedeagus. It may be the sister species of S. struyvei from the Guayanas on the East slope of Amazonian Andes. Without study of the aedeagus, both species can hardly be separated. The cones at the apical orifice of the aedeagus in S. peruanus are much longer and the apical part of the parameres is wider than in S. struyvei. Description: Length: 4.6 mm. Colouration: Dark brown; pronotum only very slightly lighter; legs and antennae light brown. Head: 0.81 mm long, 0.64 mm wide; eyes moderately large; not prominent; PS : E ratio 3.0; postocular sides parallel; posterior angles combined with posterior margin nearly semi-circular; only short central part straight; without interantennal furrows; setiferous punctation weak and sparse; on average, interstices between punctures 2 to 3 times as wide as diameter of punctures; surface without microsculpture; shiny. Antennae with first antennomere half-length of head; antennomeres 2 and 3 as long as apical width; antennomere 4 to 10 wider than long and increasing in width; antennomere 4 twice as wide as long; antennomere 10 1.5 times as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.92 mm long, 0.60 mm wide; widest in front of anterior third; anteriad, narrowed to neck in short convex curve; posteriad, sides nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation slightly deeper and denser than on head; on average, interstices between punctures twice as wide as diameter of punctures; wide midline impunctate; irregular row of punctures adjacent to midline with 13 to 14 punctures; surface without microsculpture; shiny. Elytra: 0.86 mm long, 0.75 mm wide; humeral and posterior angles sub-rectangular; sides slightly divergent posteriad; posterior margin slightly convex; widely retreated to suture; setiferous punctation deep and dense; on average, interstices between punctures half as wide as diameter of punctures; surface without microsculpture; shiny. Abdomen with fine and spares setiferous punctation; surface without microsculpture; shiny; posterior margin of male sternite and tergite VII slightly convex (similar as in Figs 19c,d). Aedeagus oval with sub-rectangular anterior angles; apical orifice on short prominence; cones at interior edge of apical orifice; relatively long; C : A ratio 0.29; sclerotised endophallus with longitudinal torsion; covered with long teeth and lobes; parameres long; straight and wide at base; shortly curved interiorly to acute apex; apex with numerous sensillae with extremely short setae; on basic shaft with one long seta.
Diagnosis: Among the similarly large species between 4 and 5 mm, S. pulcher is characterised by the light brown, nearly yellow pronotum. In this respect, it resembles S. laevis. In contrast to nearly absent posterior angles of head in S. laevis, the posterior angles of the head are more sub-rectangular in S. pulcher. Somoleptus pulcher is mainly characterised by the triangular shape of the parameres and the broad structure of the apical cones of the aedeagus. The aedeagus resembles that of S. recurvatus, but S. recurvatus is much darker and the pronotum less polished than in S. pulcher. Description: Length: 4.8 mm. Colouration: Brown; head and elytra dark brown; nearly black; pronotum light brown; slightly darkened anteriorly; legs and antennae light brown to nearly yellow. Head: 0.88 mm long, 0.67 mm wide; long oval; eyes large; PS : E ratio 2.5; posterior angles widely rounded; posterior margin convex; interantennal furrows weak; setiferous punctation moderately dense and deep; on average, interstices between punctures twice as wide as diameter of punctures; surface without microsculpture; shiny. Antennae with first antennomere as long as halflength of head; second and third antennomere triangular; elongate; at least twice as long as apical width; following antennomeres wider than long; fourth antennomere 1.5 times as wide as long; antennomere 10 twice as wide as long; antennomere 4-11 pubescent. Pronotum: 0.94 mm long, 0.58 mm wide; widest shortly behind anterior third; anteriad, convexly narrowed to neck; posteriad, slightly narrowed in central third and nearly parallel in posterior third; posterior angles shortly rounded; posterior margin slightly convex; setiferous punctation sparse; wide midline impunctate; irregular line adjacent to midline with 17-18 punctures; laterad, punctation sparser; surface without microsculpture; polished. Elytra: 0.85 mm long, 0.81 mm wide; humeral angles nearly rectangular; posteriad, sides slightly divergent; posterior angles nearly rectangular; posterior margin slightly convex; shortly retreated to suture; setiferous punctation moderately dense and deep; on average, interstices between punctures 1.5 times as wide as diameter of punctures; surface with irregular weak ground sculpture; less shiny than head and pronotum. Abdomen with setiferous punctation as dense as on elytra; microsculpture transversely reticulate; less shiny than forebody; male sternite VII and tergite VII with straight posterior margin. Aedeagus shortly oval with sub-rectangular anterior part; pair of apical cones moderately large; C : A ratio 0.31; parameres short; forming triangular plate with numerous sensillae; sensillae without setae. Sharp, 1885 Figs 27a, b;47 J Somoleptus punctulatus Sharp, 1885, 497 Type material examined: female?, holotype: Guatemala: near the city, Aceituno, leg. Champion (BMNH).

Somoleptus punctulatus
Additional material examined: Mexico: 1 male, Jalapa, leg. F. Schneider (ZMHB); 1 female, Queretaro, 16 mi. E Landa de Matamoros, 5300 ft elev., under oak bark, 18.-19.7.1970, leg. A. Newton (FMNH); 1 male, Jalisco, Puerto los Mazos, 10 mi SW Autlán, 4400 ft elev., Berlese, litter, oak-tropical deciduous forest, 25.9.1973, leg. A. Newton (FMNH); 1 female, Chiapas, 12 mi NW Ocozocoautla, 3200 ft elev., 3200 ft elev., under bark, 4.-5.9.1973, leg. A. Newton (FMNH); 1 male, 5.9 km E Bochil, 1300 m elev., riparian mesophytic forest litter, 15.9.1992 Diagnosis: Unfortunately, the abdomen of the single type specimen is destroyed. Therefore, it is uncertain if it is a male or a female and a study of the sexual structures in the last abdominal segments was impossible. The description of the male characters, therefore, is based on the non-type specimens. The species is very similar to S. parvulus in size and colouration. Somoleptus punctulatus may be separated from S. parvulus by the denser and deeper punctation of the elytra and the presence of microsculpture. It may be that both species are conspecific. However, this problem can only be solved if more specimens, in particular, more males are collected. Description: Length: 3.7 mm (estimated). Colouration: Reddish brown; head and elytra darker, blackish; base and apical margin of elytra lighter than the central parts. Head: 0.61 mm long, 0.41 mm wide; eyes moderately large; PS : E ratio 2.5; postocular sides twice as long as eyes; approximately parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation deep and dense; without distinct impunctate midline; extremely narrow parts on anterior and posterior vertex impunctate; on average, interstices between punctures 0.5 times as wide as diameter of punctures; surface without microsculpture; polished. Antennae with first antennomere half-length of head; second antennomere longer than wide; third approximately quadrate; combined half-length of first antennomere; following antennomeres nearly 2.5 times as wide as long; increasing in width; antennomere 4-11 pubescent. Pronotum: 0.76 mm long, 0.48 mm wide; widest at anterior third; anteriad, continuously convergent to neck; posteriad, nearly parallel; posterior angles sub-rectangular; posterior margin slightly convex; setiferous punctation nearly as dense and deep as on head but with wide impunctate midline; surface without microsculpture; polished. Elytra: 0.75 mm long, 0.64 mm wide; humeral and posterior angles sub-rectangular; posteriad, sides slightly divergent; posterior margin slightly retreated to suture; setiferous punctation still deeper and denser than on head and pronotum; on average, interstices between punctures shorter than 0.5 times as wide as diameter of punctures; surface with isodiametric microsculpture; moderately matt. Abdomen weak and sparse with setiferous punctation; distinctly weaker and sparser than on fore-body; posterior margin of male sternite VII with central triangular prominence; posterior margin of male tergite VII straight (similar as in Figs 21c, d). Aedeagus oval; apical cones short; C : A ratio 0.15; sclerotised endophallus narrow with wide torsion; parameres divided into slender inner lobe and plate-like outer lobe; inner lobe curved with few setae on inner face; transparent outer lobe two third as long as inner lobe.

Diagnosis:
The species resembles many black species of similar size between 4 and 6 mm and can be hardly separated without study of the aedeagus. The broad triangular parameres and the recurvate cones at the apical orifice are specific and can be used to distinguish the species from all other species of the genus. Description: Length: 5.2 mm. Colouration: Black, legs light brown; antennae darker brown. Head: 0.77 mm long, 0.58 mm wide; eyes moderately long; PS : E ratio 2.5; posterior angles combined with posterior margin semi-circular; interantennal furrows weakly present; weak transverse furrows from anterior edge of eyes to central vertex; setiferous punctation moderately deep and dense; on average, interstices between punctures 1.5 to 2 times as wide as diameter of punctures; surface without microsculpture; polished. Antennae with first antennomere slightly longer than half-length of head; second and third antennomere triangular; nearly twice as long as apical width; combined slightly longer than half-length of first antennomere; following antennomeres wider than long and increasing in width; fourth 1.5 times as wide as long; tenth twice as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.88 mm; 0.52 mm wide; widest slightly in front of anterior third; shortly convergent in smooth curve to neck; posteriad, slightly narrowed; nearly parallel; posterior angles combined with posterior margin convexly curved; setiferous punctation as dense and deep as on head; wide midline impunctate; surface without microsculpture; polished. Elytra: 0.75 mm long, 0.76 mm wide; humeral and posterior angles sub-rectangular; sides slightly divergent posteriad; posterior margin slightly retreated to suture; setiferous punctation dense and moderately deep; with irregular ground-sculpture; moderately matt. Abdomen with setiferous punctation finer than on elytra; without microsculpture; shiny; posterior margin of male sternite VII approximately semi-circular and slightly elevated; posterior margin of male tergite VII straight (similar as in Figs 9c, d), but with slight prominent centre. Metatibia with two subapical ctenidia. Aedeagus oval with sub-rectangular anterior angles; anterior angles at central orifice slightly prominent; cones at apical orifice short and broad; C : A ratio 0.18; kneed, but at apex approximately parallel; parameres short; triangular; at base extremely broad; in basic third abruptly narrowed to nearly acute apex; inner and outer face with numerous cannulate-sensillae.

Etymology:
The species name is derived from the Latin word recurvare (meaning to bend backwards) and refers to the specific structure of the cones at the apical orifice. Sharp, 1885 Figs 33a, b, 48 H Somoleptus sparsus Sharp, 1885: 497 Type material examined: male, holotype: Guatemala: near the city, Aceituno, leg. Champion (BMNH).

Somoleptus sparsus
Head: 0.76 mm long, 0.54 mm wide; eyes large; prominent; PS : E ratio 2.6; postocular sides nearly parallel; posterior angles sub-rectangular; posterior margin convex with short central part straight; interantennal furrows present; setiferous punctation moderately deep and dense; on average, interstices between punctures at least as wide as diameter of punctures; partly wider; midline impunctate; surface without microsculpture; shiny. Antennae with first antennomere half-length of head; second and third antennomere conical; slightly longer than wide; following antennomeres wider than long; increasing in width; fourth antennomere 1.5 times as wide as long; tenth antennomere nearly 2 times as wide as long; antennomeres 4-11 pubescent. Pronotum: 0.81 mm long, 0.46 mm wide; widest at anterior third; anteriad, widely narrowed in convex curve; posteriad, shortly narrowed in concave curve; in posterior third nearly parallel; posterior angles sub-rectangular; posterior margin weakly convex; setiferous punctation as dep and dense as on head; punctures in row adjacent to impunctate midline with shorter interstices; surface without microsculpture; shiny. Elytra: 0.77 mm long, 0.63 mm wide; humeral and posterior angles sub-rectangular; sides nearly parallel; posterior margin convexly curved; triangularly retreated to suture; setiferous punctation as deep and dense as on pronotum; surface without microsculpture; shiny. Abdomen with setiferous punctation as dense but finer than on elytra; setae pointing posteriad; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergite VII straight (similar as in Figs 21c, d). Aedeagus oval with anterior angles sub-rectangular; cones at apical orifice moderately long; C : A ratio 0.25; sclerotised endophallus with longitudinal torsion; covered by moderately long teeth; parameres bilobed with plate-like outer lobe and slender inner lobe; outer lobe approximately half as long as inner lobe; inner lobe with row of long setae at inner edge.
Somoleptus strigulata (Blackwelder, 1943)  Although the aedeagus of the species is unknown, which makes a certain assignment to the genus Somoleptus uncertain, the structure of the pronotum fits better to Somoleptus than to Lithocharodes (see Irmler 2021). It can be distinguished from S. curtulus by the longer elytra. In S. strigulata the elytra are approximately quadrate, whereas they are distinctly shorter than long in S. curtulus. Moreover, the punctation of the head is denser and the microsculpture on the pronotum deeper than in S. curtulus. Description: Length: 6.1 mm Colouration: Dark brown; elytra indistinctly lighter brown; legs and antennae light brown. Head: 0.98 mm long, 0.75 mm wide; long oval; eyes short; PS : E ratio 7.7; sides nearly parallel; posterior margin nearly semi-circular; interantennal furrows weak; setiferous punctation sparse and moderately deep; on average, interstices between punctures twice as wide as diameter of punctures; surface with weak isodiametric microsculpture; moderately matt. Antennae with first antennomere approximately as long as half-length of head; second and third antennomere triangular; nearly twice as long as apical width; following antennomeres wider than long and increasing in width; fourth antennomere nearly twice as wide as long; tenth antennomere 2.2 times as wide as long; antennomeres 4-11 pubescent; all antennomeres with setae. Pronotum: 1.14 mm long, 0.75 mm wide; widest in central third; anteriad, narrowed to neck in wide convex curve; posteriad, slightly narrowed in central third; posterior third nearly parallel; posterior angles shortly rounded to nearly straight posterior margin; setiferous punctation as dense and deep as on head; adjacent to narrow impunctate midline with irregular line of approximately 19 punctures; surface with wavily reticulate microsculpture; as matt as head. Elytra: 0.71 mm long, 0.73 mm wide; humeral angles obtuse; posteriad, sides divergent; posterior angles nearly rectangular; posterior margin triangularly retreated to suture; setiferous punctation slightly denser than on pronotum; setae pointing posteriad; surface with isodiametric microsculpture; as matt as on pronotum. Abdomen slightly finer and sparser punctate than forebody; setae pointing posteriad; surface with transverse reticulate microsculpture; moderately matt. Aedeagus unknown. Diagnosis: Regarding size, colouration and structure of the elytra and the aedeagus, S. struyvei closely resembles S. peruanus. The eyes of S. struyvei are larger and more prominent than in S. peruanus. In particular, the cones at the apical orifice are much shorter in S. struyvei than in S. peruanus and the parameres are different (see description of S. peruanus). The aedeagus of S. struyvei also resembles that of S. breviusculus but the cones in S. breviusculus are much shorter. In contrast to S. struyvei, the elytra of S. breviusculus are also much shorter.
Description: Length: 4.9 mm. Colouration: Black; legs and antennae brown. Head: 0.78 mm long, 0.61 mm wide; eyes large, prominent; PS : E ratio 2.4; approximately parallel; postocular angles combined with posterior margin semi-circular; interantennal furrows weak; setiferous punctation weak and sparse; on average, interstices between punctures 2-3 times as wide as diameter of punctures; small midline impunctate except two punctures in interocular area; surface without microsculpture, polished. Antennae with first antennomere distinctly longer than half-length of head; antennomeres 2 and 3 longer than wide; combined half as long as first antennomere; antennomeres 4-10 twice as wide as long and increasing in width; antennomeres 4-11 pubescent. Pronotum: 0.90 mm long, 0.52 mm wide; widest at anterior third; anteriad, narrowed in convex curve; posteriad, slightly narrowed; in posterior third approximately parallel; posterior angles combined with posterior margin semicircular; setiferous punctation slightly denser than on head but similarly deep; on average, interstices between punctures twice as wide as diameter of punctures; wide midline impunctate; irregular line adjacent to midline with 14-15 punctures; surface without microsculpture; polished. Elytra: 0.87 mm long, 0.80 mm wide; humeral and posterior angles sub-rectangular; sides slightly divergent posteriad; posterior margin curved; slightly retreated to suture; setiferous punctation similarly dense and deep as on pronotum; surface without microsculpture; polished. Abdomen with setiferous punctation as dense as on elytra; slightly finer; posterior margin of male sternite and tergite VII straight. Aedeagus approximately hexagonal with obtuse angles; C : A ratio 0.19; retreated from apex; apically with transverse setae; apical orifice on each side with two teeth; sclerotised endophallus covered partly by moderately large teeth, partly by minute teeth; in these parts transparent; parameres straight and broad; in apical part abruptly narrowed to acute apex; with numerous sensillae; at inner edge with few short setae.

Etymology:
The species honours its collector, Tim Struyve (Belgium), who found it on his excursion to French Guiana.
Diagnosis: Somolpetus subtilis is similarly small as S. parvulus and S. obsoletus. The short size of the elytra resembles those of S. parvulus but they are unicoloured in S. subtilis, whereas they have lighter spots in S. parvulus. In addition, the structure of the aedeagus is totally different from that of S. obsoletus and S. parvulus. The cones are extremely long continuing into the central lobe, whereas they are much shorter and placed at the apical orifice in S. obsoletus and S. parvulus. The parameres are triangular in S. subtilis, but divided into two lobes with slender inner lobe in the other two species. Overall, the structure of the long cones and the specific endophallus are unique in the genus. Description: Length: 3.3 mm. Colouration: Light brown; head and pronotum slightly lighter than elytra and abdomen; legs and antennae still lighter; nearly yellowish. Head: 0.62 mm long, 0.45 mm wide; eyes large; slightly prominent; PS : E ratio 2.6; parallel; posterior angles rounded but nearly rectangular; posterior margin slightly convex; setiferous punctation weak and sparse; on average, interstices between punctures 2 to 3 times as wide as diameter of punctures; surface without microsculpture; polished. Antennae with first antennomere distinctly longer than half-length of head; antennomere 2 and 3 triangular; nearly twice as long as their apical width; following antennomeres wider than long and increasing in width; fourth antennomere nearly quadrate; tenth antennomere 1.5 times wider than long; antennomeres 4-11 pubescent; all antennomeres with short setae. Pronotum: 0.74 mm long, 0.42 mm wide; widest closely behind anterior third; anteriad, narrowed in smooth curve to neck; posteriad, shortly narrowed; nearly parallel in posterior third; posterior angles obtuse; posterior margin slightly convex; setiferous punctation as weak and sparse as on head; wide midline impunctate; surface without microsculpture; polished. Elytra: 0.67 mm long, 0.62 mm wide; humeral angles nearly rectangular; sides slightly divergent to obtuse rounded posterior angles; posterior margin straight; setiferous punctation as weak and sparse as on pronotum; surface with extremely weak ground sculpture; nearly polished. Abdomen slightly denser punctate than fore-body; weak transverse microsculpture, surface shiny; male sternite VII and tergite VII without process; simply convex to nearly straight. Aedeagus oval; at apical orifice with pair of long cone-like process; increasing in width from base to apex; C : A ratio 0.47; endophallus divided into two sclerotised stripes covered by minute teeth; forming a loop of two circles; parameres triangular; not divided into two lobes; at inner edge with several cannulate sensillae; at outer edge and on basal plate more sensillae. Diagnosis: Somoleptus triangulus has short elytra and short eyes. Among the similarly large species, e.g. S. brunneus, S. longiceps, and S. ovatus, S. triangulus is conspicuous by the divergent postocular sides of the head, which is found also in S. brunneus. Compared to S. brunneus, the eyes of S. triangulus are still shorter. In contrast to S. brunneus, the male sternite VII is prominent and not emarginate.

Somoleptus triangulus
Description: Length: 4.0 mm. Colouration: Light brown; elytra, legs, and antennae lighter brown. Head: 0.67 mm long, 0,56 mm wide; eyes short; not prominent; PS : E ratio 5.9; postocular sides divergent; posterior angles sub-rectangular; posterior margin straight; interantennal furrows extremely weak; setiferous punctation moderately deep and irregularly dense; on average, interstices between punctures 1-2 times as wide as diameter of punctures; on posterior vertex sparser than on anterior vertex; wide midline impunctate; surface without microsculpture; polished. Antennae with first antennomere slightly longer than half-length of head; second and third antennomere longer than wide; second 1.5 times as long as third; antennomeres 4 to 10 wider than long and increasing in width; fourth antennomere twice as wide as long; tenth antennomere 2.2 times as wide as long; antennomeres 4 to 11 pubescent. Pronotum: 0.83 mm long, 0.54 mm wide; widest shortly behind anterior third; anteriad narrowed in smooth curve; sides in posterior half nearly parallel; posterior angles sub-rectangular; posterior margin nearly straight; setiferous punctation as dense and deep as on head; wide midline impunctate; irregular line of punctures adjacent to midline with approximately 16-17 punctures; surface without microsculpture; polished. Elytra: 0,55 mm long, 0.61 mm wide; humeral angles absent; sides posteriad slightly divergent; posterior angles rectangular; posterior margin triangularly retreated to suture; setiferous punctation as deep but slightly denser than on pronotum; on average, interstices between punctures as wide as diameter of punctures; surface without microsculpture; shiny. Abdomen with setiferous punctation as dense as on elytra but less deep; with weak transversely reticular microsculpture; shiny; posterior margin of male sternite VII triangularly prominent; posterior margin of male tergite VII straight (similar as in Figs 21c, d). Aedeagus oval with anterior angles sub-rectangular; C : A ratio 0.19; endophallus with long sclerotised spines at base; anteriorly more transparent and without teeth or spines; parameres nearly twice as long as cones; divided into two lobes; outer lobe plate-like; inner lobe slender; nearly twice as long as outer lobe; with row of few setae at inner edge; another row of four setae near base.

Etymology:
The species name is derived from the same Latin word (meaning triangle) and refers to the triangular shape of the head. Diagnosis: Among the large species of >= 6 mm length with long elytra, S. tschirnhausi is characterised by the absence of distinct posterior angles of the head. Moreover, the parameres of the aedeagus differ by the more elongate shape from the similarly large S. elongatus with sub-rectangular posterior angles of the head. In S. elongatus, the parameres are much broader and plate-like.

Somoleptus tschirnhausi
Description: Length: 6.0 mm. Colouration: Black; elytra dark brown; indistinctly lightened at base; with small yellow spot at posterior angles; legs and antennae light brown; last antennomere with yellow apex. Head: 0.78 mm long, 0.54 mm wide; eyes moderately large; not prominent; PS : E ratio 3.2; shape approximately oval; postocular sides slightly divergent; posterior angles widely rounded; interantennal furrows deep; reaching mid of eyes; setiferous punctation irregularly distinct and sparse; on average, interstices between setiferous punctures 3 to 4 times as wide as diameter of punctures; vertex with impunctate midline; surface without microsculpture; shiny. Antennae first antennomere half-length of head; antennomere 2 and 3 conical; elongate; following antennomeres transverse; second and third antennomere each as long as fourth and fifth antennomere combined; antennomere 10 twice as wide as long; antennomeres 4-11 pubescent; antennomeres 4 to 10 with apical crown of short setae. Pronotum: 0.83 mm long, 0.54 mm wide; widest in anterior third; anteriad, convergent to neck in smooth curve; sides in posterior third approximately parallel; posterior angles obtusely rounded; punctation moderately dense and deep; narrow midline impunctate; irregular line of punctures adjacent to smooth midline with 12 to 14 punctures; along sides several setiferous punctures; between normal punctation with weak micro-punctures; surface slightly matt. Elytra: 0.76 mm long, 0.71 mm wide; widest at posterior angles; posterior angles sub-rectangular; humeral angles distinct; sides slightly divergent to posterior angles; posterior margin retreated to suture; punctation distinctly deeper and denser than on head and pronotum; in parts nearly coriaceous; on average, interstices between puncture as wide as or shorter than diameter of punctures; between large punctures with weak micro-punctures; surface slightly matt. Abdomen densely covered by setiferous punctation; male sternite VII with minute triangular incision at posterior margin; posterior margin of male tergite VII straight. Mesotibia with 4, metatibia with 3 subapical ctenidia. Aedeagus oval with sub-rectangular anterior angles; cones at apical orifice short; C : A ratio 0.11; endophallus with two strings of large teeth; like a zip-fastener; combined to a wide stripe covered by knops; twisted posteriad and bent back to front; parameres triangular; elongate; covered by several sensillae.