Fourteen new species of Oecetis McLachlan, 1877 (Trichoptera: Leptoceridae) from the Neotropical region

Background The caddisfly genus Oecetis currently contains 534 valid species. Its larval stages are found in freshwaters around the world. The adults can be distinguished from other Leptoceridae by the unbranched forewing M vein and the exceptionally long maxillary palps. In the Neotropical region, 55 species of Oecetis have been recorded and most of them can be placed in one of the six species groups known from this biogeographical region: the avara-, falicia-, inconspicua-, punctata-, punctipennis-, and testacea-groups. More than 50% of the known diversity of Neotropical Oecetis has been described in the past 40 years. Here, we describe an additional 14 new species of Oecetis to further document the diversity of this genus in the Neotropical region. Methods The descriptions and illustrations presented here are based on male specimens. Specimens were collected with Malaise traps or ultraviolet light traps. They were preserved in alcohol or pinned as stated in material examined section. Specimens had their genitalia prepared in 85% lactic acid to better observe internal characters and illustrations were aided by the use of a microscope with drawing tube attached. Results and Discussion This study raises the number of species of Oecetis in the Neotropics from 55 to 69. Eight of the new species presented here could not be reliably placed in one of the known species groups (Oecetis acuticlasper n. sp., Oecetis flinti n. sp., Oecetis carinata n. sp., Oecetis cassicoleata n. sp., Oecetis blahniki n. sp., Oecetis gibbosa n. sp., Oecetis licina n. sp., and Oecetis pertica n. sp.). The others are placed in the punctata-group (Oecetis bidigitata n. sp., Oecetis quasipunctata n. sp.), testacea-group (Oecetis plenuspinosa n. sp.), and falicia-group (Oecetis calori n. sp., Oecetis hastapulla n. sp., Oecetis machaera n. sp.). Most of the diagnostic characters rely on structures of the inferior appendages and phallic apparatus, and the shape of tergum X.


INTRODUCTION
Oecetis McLachlan, 1877, is a genus within the caddisfly family Leptoceridae (Insecta: Trichoptera) with 534 valid species. The species in the genus are usually collected along included species in this group are: O. punctipennis (Ulmer), O. iguazu Flint and O. connata Flint. The testacea-group is diagnosed as having a honeycomb microstructure covering abdominal tergum VIII and usually preceding terga, although their function is yet unknown (Malicky, 2005). Henriques-Oliveira, Dumas & Nessimian (2014) described Oecetis iara, the only known species so far in the Neotropics with the honeycomb texture on abdominal terga. However, in the Nearctic region, there are species that share this morphological characteristic such as O. cinerascens (Hagen) and O. persimilis (Banks).
Significant contributions on the taxonomy of Oecetis in the Neotropical region were made in the last 40 years by several authors (Flint, 1974;Bueno-Soria, 1981;Rueda-Martín, Gibon & Molina, 2011;Blahnik & Holzenthal, 2014;Henriques-Oliveira, Dumas & Nessimian, 2014;Quinteiro & Calor, 2015). The species proposed by those authors account for more than 50% of the currently known species in the Neotropical region, but it is known that there is much more to do in caddisfly taxonomy in the Neotropics (Holzenthal & Calor, 2017). Despite this increasing description of the Neotropical fauna, much of the region's biodiversity likely still remains unknown. There are species already deposited and labeled in museums waiting to be described. This study advances the knowledge of Neotropical caddisfly diversity by describing fourteen new species of Oecetis based on morphological characteristics of the adult male.

MATERIALS AND METHODS
The specimens were primarily collected by use of ultraviolet fluorescent light bulbs placed in front of a white sheet, pan light traps (Calor & Mariano, 2012), and Malaise traps. Those specimens collected on the white sheets are preserved dried and pinned. The remaining specimens were preserved in 80% ethyl alcohol.
For a more accurate study of some genital characters, genitalia were removed and cleared in 85% lactic acid (Blahnik, Holzenthal & Prather, 2007) at 115 C for approximately 1 h, washed with distilled water, and stored in 0.2 mL vials in approximately 50 mL of glycerin in the vial bottom. each species is given by country and state, province, or department, summarized by the map presented at the end of the descriptions. The map was built using the website SimpleMappr (available at http://www.simplemappr.net). Species distributions are available as a Supplemental Data File (.kml) and can be opened in Google Earth. For those specimens with collection labels that did not include geographical coordinates, approximate coordinates were used to plot into the map based on the other label data.
The electronic version of this article in portable document format will represent a published work according to the International Commission on Zoological Nomenclature (ICZN), and hence the new names contained in the electronic version are effectively published under that Code from the electronic edition alone. This published work and the nomenclatural acts it contains have been registered in ZooBank, the online registration system for the ICZN. The ZooBank LSIDs (Life Science Identifiers) can be resolved and the associated information viewed through any standard web browser by appending the LSID to the prefix http://zoobank.org/. The LSID for this publication is: urn:lsid: zoobank.org:pub:ED02CA58-B074-45A6-AAC7-48FB48B97BA8. The online version of this work is archived and available from the following digital repositories: PeerJ, PubMed Central and CLOCKSS.

Taxonomy
Oecetis acuticlasper Quinteiro & Holzenthal, n. sp. urn:lsid:zoobank.org:act:046E520D-07ED-4892-BBDE-BE0654C5BE95 Diagnosis. This species can be distinguished from all other Oecetis by the slender dorsal lobe of tergum X, which is almost as long as the preanal appendage and laterally divided at its apex; and by the shape of the inferior appendage, with its enlarged, somewhat triangular ventral lobe, discrete, also triangular dorsal lobe, and a distal lobe, which is distinctly constricted and narrowed in the apical third of the appendage.
This species is morphologically similar to O. maspeluda Botosaneanu, 1977. Both of them have a dorsoventrally divided tergum X, short phallic apparatus, and a somewhat triangular inferior appendage. However, the dorsal lobe of tergum X in this new species is much shorter than in Oecetis maspeluda and laterally divided at the apex. Also, the new species has the ventral margin of inferior appendage slightly concave in lateral view, giving an almost 90 angle between the ventral and distal lobes, while in Oecetis maspeluda this margin is smooth and almost straight. Additionally, the constriction present at the last third of the inferior appendage's length in the new species is unique in Oecetis. This species does not have features to place it in any known species group.
Important adjunct characters, such as the presence of dark spots on the forewing and the position of the main forks, are easily observable. This new species is similar to O. pratti Denning, 1947 since both have tergum X divided dorsoventrally, with a deflexed dorsal lobe, and an inferior appendage without dorsal and ventral lobes. However, the inferior appendage of this new species has a distinct constriction at its base, while Oecetis pratti has the inferior appendage uniformly wide along its entire length. Oecetis flinti n. sp. has its preanal appendage short and ovoid, somewhat lobulate in lateral view, while in Oecetis pratti they are long and digitate. The most evident characteristics of this new species that differ from Oecetis pratti are the presence of a phallic spine in the phallic apparatus and the elongate tergum IX, which is much longer than sternum IX. This species does not fit within one of the recognized species groups.
Thorax. Pterothorax yellowish brown; forewing yellow; dark bands over cord present ( Fig. 2A); dark spots on M-Cu fork, on basis of Rs, on basis of Cu 1 and Cu 2 , on junction of anal veins ( Fig. 2A); forks I and V rooted; sectoral crossvein (s) not aligned with r-m ( Fig. 2A). Hind wing with forks I and V present (Fig. 2B). Legs pale yellow, mid leg with longitudinal row of spines on tibia and tarsal segments. Tibial spur formula 1,2,2; apical spur of fore tibia very small.
Abdomen. Segment IX uneven, tergum IX longer than sternum IX; acrotergite absent ( Fig. 2C). Preanal appendage slightly wider than long (ovoid), bearing apical setae (Figs. 2C and 2D). Tergum X, in lateral view, not divided into dorsal and ventral lobes, undivided medially, composed of single elongated lobe, broad basally, tapering apically, apex acuminate (Figs. 2C and 2D)  Taxonomic comment: The available specimens had damaged wings so it was not possible to illustrate an entire wing.
Etymology. The specific epithet honors our colleague Dr. Oliver S. Flint for his contributions to caddisfly taxonomy and his extensive studies in the Neotropical region.
This new species is very similar to O. inflata Flint, 1974 since they both share a deeply divided tergum X, forming two slender and terete processes. Additionally, they resemble each other in that the preanal appendages are short and digitate, the phallic apparatus is short and strongly curved ventrally, and the forewing venation is almost identical. However, the new species has the ventral lobe of the inferior appendage quadrate and greatly enlarged in relation to the distal lobe. Oecetis inflata has the ventral lobe of the inferior appendage somewhat quadrate, but the ventral margin is very smooth and not as angled as in the new species. Additionally, the distal lobe of the inferior appendage in Oecetis carinata is reduced compared to Oecetis inflata. This new species does not have characteristics that allow placement in a known species group.
Abdomen. Segment IX annular, short; acrotergite absent ( Fig. 3C)  Diagnosis. This species can be distinguished from the other species in Oecetis by its inferior appendage, which has the distal lobe curved, forming an obtuse angle along its length, and by the enlarged phallobase, with a lamellate process distally over the endotheca.
This new species has no similar species in the Neotropical region. Some species, such as O. testacea (Curtis, 1834) or O. cinerascens (Hagen, 1861), share an enlarged phallic apparatus, but both of them have phallic spines and a modified, reticulate tergum VIII, both characteristics not present in this species. Also, the inferior appendage of the new species is very distinct, having a rounded, slightly projected dorsal lobe, which becomes forward-pointing due to the concavity of the distal lobe, which forms an obtuse angle. Additionally, the presence of a flap-like projection on the dorsodistal margin of the phallobase is very conspicuous. This is another new species that cannot be placed in a named species group.
Oecetis bidigitata Quinteiro & Holzenthal, n. sp. urn:lsid:zoobank.org:act:7A089FD8-F3F1-4339-898F-98DE402E3C81 Diagnosis. This new species can be distinguished from the others in the punctata group by its stirrup-like phallotremal sclerite and by its inferior appendage, with a very short ventral lobe and two digitate projections bearing strong and thick setae on the distal lobe.
This species is very similar to O. knutsoni Flint, 1981 and O. quasipunctata n. sp. However, this species, differs from Oecetis knutsoni and Oecetis quasipunctata n. sp., by having a distinct stirrup-like phallotremal sclerite, not present in the other two species. Additionally, Oecetis bidigitata n. sp. has only two digitate projections bearing strong and thick setae on the apex of the distal lobe of inferior appendage, while Oecetis knutsoni and Oecetis quasipunctata n. sp. have four projections.
Oecetis quasipunctata Quinteiro & Holzenthal, n. sp. urn:lsid:zoobank.org:act:B7E84B92-234B-46F1-BDF0-9D74D1CA9AB9 Diagnosis. This new species can be distinguished from the others in the punctata group by its inferior appendage, with the ventral lobe very reduced and forming an acute angle with the distal lobe, and also by the nearly straight distal lobe.
This new species is very similar to Oecetis knutsoni, Oecetis bidigitata n. sp., and Oecetis punctata (Nav as, 1924) (Fig. 7). Oecetis bidigitata has only two digitate projections apically on the distal lobe of the inferior appendage, while Oecetis knutsoni, Oecetis punctata, and Oecetis quasipunctata n. sp. have four projections. Oecetis punctata has a concave inner surface of the inferior appendage (Fig. 7E, best seen in ventral view), while Oecetis knutsoni, Oecetis bidigitata n. sp., and Oecetis quasipunctata n. sp. have the inner surface straight (Fig. 6E). The main differences between Oecetis knutsoni and this new species are in the inferior appendage. Oecetis knutsoni has an inferior appendage with a long ventral lobe forming a straight angle with the distal lobe, while this new species has a very reduced ventral lobe forming an acute angle with the distal lobe. Additionally, Oecetis knutsoni has the apex of the distal lobe slightly bent posteriorly, while the new species has it nearly straight.
Abdomen. Segment IX annular, very short; two acrotergites present dorsolaterally (Fig. 6C)    Etymology. From Latin quasi = appearing as if, similar. This is a reference to the resemblance of this new species with Oecetis punctata (Nav as, 1924), illustrated in Fig. 7.
Oecetis calori Quinteiro & Holzenthal, n. sp. urn:lsid:zoobank.org:act:58B08D3F-32E2-4408-9D62-24A46FAB2B5F Diagnosis. This new species can be diagnosed from the others in the falicia group by its three phallic spines and by the inferior appendage with a small, discrete, quadrate basal projection with a truncate apex, and a triangular, protruding, and very angular ventral lobe.
This new species is similar to O. fibra Chen & Morse in Quinteiro & Calor, 2012 and to O. acarati Angrisano & Sganga, 2009; all of them share a segment IX with slender, ventrally directed dorsolateral processes with no ramifications, and a terete, apically rounded distal lobe on the inferior appendage. However, none of the described species possess three spines in the phallic apparatus as in the new species. Additionally, the inferior appendage of Oecetis fibra has a quadrate ventral lobe with smooth margins, while in Oecetis acarati and the new species this lobe is triangular. Oecetis acarati has the ventral lobe of inferior appendage with a smooth margin and no dorsal lobe, while Oecetis calori, n. sp. has a discrete quadrate dorsal lobe and a triangular flattened ventral lobe.
Abdomen. Segment IX annular, short, bearing pair of dorsolateral processes; processes slender, bent ventrad, cylindrical, tapering posteriorly, same length as phallic apparatus; acrotergite absent (Figs. 8C and 8D). Preanal appendage long, digitate, bearing apical setae (Figs. 8C and 8D). Tergum X, in lateral view, divided into dorsal and ventral lobes; dorsal lobe modified into single cylindrical structure, apex digitate, same length as ventral lobe, with short apical setae (Figs. 8C and 8D); ventral lobe deeply divided laterally, forming two cylindrical lobules, apices rounded (Figs. 8C and 8D, black arrowheads). Inferior appendage 1-segmented, broad at base, setose; dorsal lobe in lateral view quadrate, discrete (Figs. 8C and 8E); ventral lobe, in lateral view, quadrate (Figs. 8C and 8E); distal lobe narrow, tapering posteriorly, apex rounded (Figs. 8C and 8E); short, stout spine-like setae present on inner surface (Fig. 8E). Phallic apparatus bilaterally symmetrical, curved downward, cylindrical, elongate, membranous apically (Figs. 8F-8H); apex elongate, in caudal view (Fig. 8G). Three phallic spines present, curved downward ( Fig. 8F and 8G). One phallotremal sclerite present, horseshoe-shaped, with discrete concavities on sides (Figs. 8G) Diagnosis. This new species can be discriminated from the others in the falicia group by the very elongate dorsal lobe of tergum X, with its slightly clavate apex, the divided apex of the inferior appendage, and by the elongate, asymmetrical, dorsolateral processes on segment IX. This new species is very similar to O. prolongata Flint, 1981, since both of them have an elongate and terete dorsal lobe of tergum X, an inferior appendage with the apex divided, and the dorsolateral processes of segment IX asymmetrical. However, this new species has the apex of dorsal lobe of tergum X clavate, while Oecetis prolongata has it uniform in width along its entire length. Also, Oecetis hastapulla n. sp. has the dorsolateral processes of segment IX longer than those of Oecetis prolongata and the process on the right side of the body is bent posteriorly, while those of Oecetis prolongata are bent ventrally.
Distribution. Costa Rica (Guanacaste, Limó n).  Etymology. From Latin hasta = spear, pullus = dark-colored, blackish. This is a reference to the sclerotized tips of the dorsolateral processes and tergum X.
Oecetis plenuspinosa Quinteiro & Holzenthal, n. sp. urn:lsid:zoobank.org:act:9C9C4C21-B3F3-454C-B5B3-A1D9709ABBCF Diagnosis. This new species can be placed close to those of the testacea-group as defined by (Malicky, 2005), due to the presence of reticulate modifications on abdominal segments V-VIII. Oecetis plenuspinosa can be distinguished from the other species of Oecetis by the shape of the inferior appendage, which lacks dorsal and ventral lobes, by the ventral lobe of tergum X, with two lateral, posterior pointing, digitate projections, and by the distinctly clavate dorsal lobe of tergum X. Additionally, the phallic apparatus has 10 short spines, distributed symmetrically in two groups of five.
In the Neotropical region the only similar species, described to date, is O. iara Henriques-Oliveira, Dumas & Nessimian, 2014. Oecetis plenuspinosa, n. sp. differs from Oecetis iara due to its dorsal lobe of tergum X, with clavate apex, while Oecetis iara has the same structure broad basally, tapering toward an acute apex. Also, the new species has two digitate processes on the ventral margin of the ventral lobe of tergum X and a truncate apex on the inferior appendage, while Oecetis iara does not have these processes on tergum X and has the inferior appendage with the apex digitate.
Thorax. Pterothorax yellowish brown; forewing yellow; dark bands over cord absent; dark spots absent on wing; forks I and V rooted; sectoral crossvein (s) not aligned with r-m. Hind wing with forks I and V present. Legs yellowish brown, mid leg with longitudinal row of spines on tibia and tarsal segments. Tibial spur formula 1,2,2.
Oecetis machaera, n. sp. is similar to O. prolongata Flint, 1981 due to the short, slightly ventrally bent, short dorsolateral process on segment IX. However, Oecetis prolongata has the ventral lobe of the inferior appendage absent. Oecetis machaera, n. sp. has the ventral lobe distinctly projected, cylindrical, and with an acute apex. Additionally, the phallic apparatus of Oecetis prolongata is very long and strongly bent ventrally, while the phallic apparatus of the new species is short and almost straight.
Thorax. Pterothorax yellowish brown; forewing yellowish brown; dark bands over cord absent; dark spots absent; forks I and V rooted; sectoral crossvein (s) not aligned with r-m. Hind wing with forks I and V present. Legs yellowish brown, mid leg with longitudinal row of spines on tibia and tarsal segments. Tibial spur formula 0,2,2.
Distribution. Brazil (Amazonas). Etymology. From Latin machaera = bent sword from ancient Greece, dirk, dagger. This specific epithet refers to the shape of the dorsolateral processes on segment IX in dorsal view, resembling the bent blade of some swords. Diagnosis. This species can be distinguished from other Oecetis by a combination of characters. It has tergum X divided dorsoventrally, segment IX with two lateral rounded processes, projecting between the dorsal and ventral lobes of tergum X, the endotheca bilobed, and the inferior appendage with the ventral margin of the distal lobe angular, and a ventral lobe that is projecting and cylindrical, with a rounded apex.
This new species is similar to O. gibbosa, n. sp., O. traini Rueda-Martín, Gibon &Molina, 2011, andO. rafaeli Flint, 1991 due to the presence of a distinct lateral process on segment IX and its short phallic apparatus. However, in Oecetis traini and Oecetis rafaeli the lateral processes are slender with acute apices, while in Oecetis blahniki, n. sp. and Oecetis gibbosa, n. sp. the apices are rounded, uniformly wide along their lengths, and project between the dorsal and ventral lobes of tergum X. The diagnostic difference between the two new species relies especially on the shape of the inferior appendage. Oecetis blahniki, n. sp. has the ventral margin of the distal lobe strongly angular and a projecting, cylindrical ventral lobe, while Oecetis gibbosa, n. sp. does not have a ventral lobe and its dorsal and distal lobes are terete and elongate. Additionally, Oecetis blahniki, n. sp has the endotheca bilobed, while in Oecetis gibbosa, n. sp. it is single lobed. This species does not have features to place it in any known species group.
Thorax. Pterothorax yellowish brown; forewing brown; dark bands over cord absent; dark spots absent; forks I and V rooted; sectoral crossvein (s) not aligned with r-m. Hind wing with forks I and V present. Legs yellowish brown, mid leg with longitudinal row of spines on tibia and tarsal segments. Tibial spur formula 0,2,2.
Etymology. This specific epithet honors our colleague Roger J. Blahnik for his contributions to caddisfly taxonomy and systematics.
Oecetis gibbosa Quinteiro & Holzenthal, n. sp. urn:lsid:zoobank.org:act:3118C6F6-3776-4624-B2E2-9615553CF62A Diagnosis. This species can be differentiated from the other Oecetis by its dorsoventrally divided tergum X, the presence of two lateral processes on segment IX with their apices truncate and projecting between the lobes of tergum X, and by the inferior appendage with an elongate, cylindrical distal lobe and dorsal lobe that is slightly clavate apically and with a rounded, mesal lobe at midlength.
This new species is similar to Oecetis traini Rueda-Martín, Gibon &Molina, 2011, O. rafaeli Flint, 1991, andO. blahniki, n. sp. due to segment IX bearing a lateral process and also the short phallic apparatus. However, the lateral processes on segment IX in Oecetis traini and Oecetis rafaeli are slender, with acute apices, while the new species has them somewhat quadrate. Oecetis gibbosa, n. sp. differs from Oecetis blahniki, n. sp. in the lateral projections of segment IX, which have their apices truncate in Oecetis gibbosa, n. sp., while Oecetis blahniki, n. sp. has them rounded. Also, Oecetis gibbosa, n. sp. has the inferior appendage with elongate dorsal and distal lobes, and with an inner lobe on the dorsal lobe, while Oecetis blahniki, n. sp. does not have a developed dorsal lobe, and the distal lobe has a very angular ventral margin. Like some of the previous species presented here, this new species does not present any distinct characteristic that would allow us to place it in a species group.
Thorax. Pterothorax yellowish brown; forewing brown; dark bands over cord absent; dark spots absent; forks I and V sessile; sectoral crossvein (s) not aligned with r-m. Hind wing with forks I and V present. Legs yellowish brown. Tibial spur formula 0,2,2.
Etymology. From Latin gibbosus = very humped. This species name is a reference to the projection observed at the mid region of the inferior appendage in caudal view.
Oecetis pertica n. sp. Quinteiro & Holzenthal, Diagnosis. Oecetis pertica n. sp. can be distinguished from the other Oecetis by the long and cylindrical dorsal lobe of tergum X, together with the somewhat quadrate dorsal lobe of the inferior appendage with its apex truncate, and the presence of a protruding ventral lobe on the inferior appendage with a very angular margin and acute apex in lateral view. Also, the very conspicuous phallic spines are divided into two groups in different regions of the phallic apparatus. Finally, the quadrate lateral lobe on segment IX of this species is unique in Oecetis.
This species has the inferior appendage similar to O. doesburgi (Flint, 1974), since both have a C-shaped incision between dorsal and distal lobes, and a dorsal lobe that is broad at its base, with its apex projecting distally. The new species has the dorsal lobe of inferior appendage with distinct truncate apex, whereas Oecetis doesburgi presents it rounded. Also, Oecetis doesburgi has the distal lobe enlarged apically, while Oecetis pertica n. sp. has it narrow. The long dorsal lobe of tergum X and the mesally divided ventral lobe of tergum X of this new species are similar to O. prolongata Flint, 1981, but O. pertica n. sp. does not have the dorsolateral processes on segment IX that are diagnostic of the falicia-group and present in Oecetis prolongata. Finally, O. rafaeli Flint, 1991, and O. blahniki n. sp. also have a pair of lateral processes on segment IX, as well as Oecetis pertica n. sp., but neither of them has the lateral process quadrate, as in the new species. This new species does not have diagnostic characters that allow us to place it in a known species group.
Thorax. Pterothorax yellowish brown; forewing yellowish; small patches of dark setae present at junction of most veins, with patches of white setae adjacent to these; forks I and V sessile; sectoral crossvein (s) not aligned with r-m. Hind wing with forks I and V present. Legs yellowish brown. Tibial spur formula 0,2,2.
Distribution. Brazil (Amazonas). Diagnosis. This species does not have characters that allow us to place it in a diagnosed species group. However, it can be distinguished from the other Oecetis by the enlarged dorsal lobe of tergum X, the triangular lateral process of segment IX, and the distinctly curved inferior appendage.
Oecetis licina n. sp. is similar to Oecetis gibbosa n. sp., since they both share a segment IX lateral process protruding underneath tergum X, as well as a cylindrical dorsal lobe of tergum X and a phallic apparatus that is cylindrical, slightly curved ventrally and bearing one phallic spine. Oecetis licina n. sp. is also similar to Oecetis blahniki n. sp. based on the broad, mesally curved distal lobe of the inferior appendage and the rounded preanal appendage. However, Oecetis licina n. sp. and Oecetis gibbosa n. sp. differ greatly in the inferior appendage shape. Oecetis gibbosa n. sp. has the dorsal lobe of inferior appendage terete, with apical and mesal inner projections. Oecetis licina n. sp. has the dorsal lobe of inferior appendage discreetly projected and rounded. The distal lobe of the inferior appendage in Oecetis licina n. sp. is conspicuously enlarged compared to the terete distal lobe of inferior appendage in Oecetis gibbosa n. sp. Also, the phallic apparatus in Oecetis licina n. sp. is disproportionally large compared to the remainder of the genitalia. Compared to Oecetis blahniki, n. sp., Oecetis licina n. sp. has the ventral lobe of inferior appendage absent, whereas Oecetis blahniki n. sp. has it cylindrical, with acuminate apex. Also, the lateral processes on segment IX of Oecetis licina n. sp. are broad at base and triangular, with acute apex, while Oecetis blahnik n. sp. has them cylindrical throughout, with rounded apex.
Thorax. Pterothorax yellowish brown; forewing light brown; faint band over cord; dark spots apically; forks I and V sessile; sectoral crossvein (s) not aligned with r-m. Hind wing with forks I and V present. Legs yellowish brown. Tibial spur formula 0,2,2.

Concluding remarks
This study raises the number of Oecetis in the Neotropics from 55 to 69 species. The new species distributions are summarized in Fig. 16. It is noticeable that some of them are only known by their holotype specimen since it was the only material available so far. Although this is not the ideal situation, we choose to describe these new species instead of letting them sit in museum collections for up to 20 years, as it can be seen in the case of Oecetis pertica, n. sp. We hope in the future, new information about their behavior or morphological variation can be provided as additional specimens are observed and collected.
Even with our contribution on the Neotropical diversity of Oecetis, many other questions remain unanswered. In this study, eight new species do not present diagnostic characters that allow us to place them in the already proposed taxonomic groups. This may be an indication that much of the diversity of the genus is still to be discovered, especially in Amazonia where many unexplored areas may harbor new species.
Another issue is the absence of a phylogenetic hypothesis of Oecetis species. It has been suggested that the avara-and punctata-groups are closely related (Blahnik & Holzenthal,

2014).
Other than this, there is no further phylogenetic information on Oecetis species or groups of species. Since the phylogenetic relationships among species remain unclear, it is difficult to determine the placement of certain species to species group, for example. In this way, a phylogenetic study would be of much value to identify the character diversity present in Oecetis and how these characters are related to each other. Also, a phylogenetic hypothesis should properly evaluate the delimitation of the already proposed taxonomic groups (e.g., avara-, inconspicua-groups). Considering that some of the new species described here do not fit in any species group diagnosis, perhaps a re-delimitation of those groups is necessary. Since the genus currently contains more than 500 species divided in no more than a dozen species groups, a phylogenetic hypothesis becomes essential to a stable taxonomy with well circumscribed species groups.