﻿Four new species of mygalomorph spiders (Araneae, Halonoproctidae and Theraphosidae) from the Colombian Pacific region (Bahía Solano, Chocó)

﻿Abstract The Colombian Pacific coast is an amazing natural region, immersed in one of the most unknown biodiversity hotspots in the world. An expedition carried out in the north of this area, at the Jardín Botánico del Pacífico (JBP) in Bahía Solano, Chocó, focused on studying the diversity of the mygalomorph spider fauna, allowed us to discover four new species included in the families Halonoproctidae and Theraphosidae. The trapdoor species Ummidiasolanasp. nov., and the theraphosids species Euthycaeluscunampiasp. nov. (Schismatothelinae), Melloinapacificasp. nov. (Glabropelmatinae), and Neischnocolusmecanasp. nov. (Theraphosinae) are illustrated, diagnosed, and described in detail. Photographs of somatic features and copulatory organs and a distribution map are provided. Morphological, taxonomical, and biogeographical aspects are discussed for each species. All these taxonomic novelties represent the first records of these genera for the region, expanding the range of geographic distribution of each of them. This work constitutes the first effort focused on characterizing the community of Mygalomorphae species in the Chocó Biogeographic Region.


Introduction
The enigmatic groups of Mygalomorphae spiders, known in a broad sense as tarantulas in America, constitute approximately 6% of the total number of spider species described (Bond et al. 2012). Primarily distributed in the tropics, most mygalomorph spiders remain to be discovered Opatova et al. 2019;Montes de Oca et al. 2022). They include hairy spiders (tarantulas sensu stricto), trapdoor spiders, funnel-web spiders, millimeter-sized spiders with little use of the silk, bald-legged spiders with the ability to attach substrate to their bodies, among other medium-sized spiders (Raven 1985;Hedin and Bond 2006;Bond et al. 2012). They are predatory animals, relatively generalists of other arthropods, most of them with terrestrial and fossorial habits, even though some groups present arboreal habits (Coyle 1986;. While a few groups of trapdoor spiders can perform short-range ballooning (Bristowe 1939;Coyle 1983Coyle , 1985Coyle et al. 1985;Ferretti et al. 2013;Rossi et al. 2021), mygalomorph spiders are primarily terrestrial and relatively sedentary (Raven 1980(Raven , 1985(Raven , 2010. Consequently, many groups have restricted geographic distributions and high levels of endemism, which makes them a highly informative group for conservation studies, environmental monitoring, and biogeography research (Raven 2010;Foelix 2011;Ferretti et al. 2012Ferretti et al. , 2014Perafán et al. 2020). In this way, many unexplored areas, especially in megadiverse regions, have a high potential for new mygalomorph species to be discovered.
The Colombian Pacific region is a fascinating area for its biological characteristics because it's located in the hearth of the Chocó Biogeographic Region. This area constitutes a global biodiversity hotspot, the ninth most biodiverse in the world and one of the most unknown (Cano et al. 2018;Pérez-Escobar et al. 2019). The Colombian Pacific region is distinguished by its immense biodiversity, reported in numerous studies focused especially on birds, mammals, amphibians, reptiles, fishes and plants (e.g., Myers et al. 2000;Hilty and Brown 2001;Mosquera et al. 2007;Sánchez-Gárcés 2017;SIB 2022), and to a lesser extent in some groups of arthropods: myriapods, hemipterans, dipterans, hymenopterans, among others (Martínez-Torres et al. 2011;Padilla-Gil and Arcos 2011;Escovar et al. 2013;González-Córdoba and Montoya-Lerma 2014;Lopez et al. 2014;Padilla-Gil 2017;Narváez-Vásquez et al. 2021). Studies about its arachnid diversity are scarce in the literature, and those addressing Mygalomorphae altogether absent (Paz 1988;Paz and Raven 1990;Perafán and Valencia-Cuellar 2018).
Despite the great potential that Colombia has to become a worldwide reference on Mygalomorphae diversity, due to its geographical location and its enormous variety of ecosystems, only 34 of the 50 species described for the country are known by both sexes, and most of them are distributed in the Andean region WSC 2023). This scenario highlights the need to conduct studies that complement the taxonomic gaps and the scarce information that exists in other natural regions that have been little explored (Cifuentes et al. 2016;Perafán and Valencia-Cuellar 2018;Valencia-Cuellar et al. 2019). The taxonomic novelties presented in this paper are part of the results obtained from a biological expedition carried out in the Jardín Botánico del Pacífico (JBP), focused on Mygalomorphae spiders. The JBP, located in Bahía Solano, is a tourist area and natural reserve that plays a key role in the conservation of the tropical rainforest and mangroves of the Colombian Chocó Biogeographic Region (Fig. 1).
In this first approach to the knowledge of the Mygalomorphae fauna from the rainforest of the Colombian Pacific, we illustrate, describe, and discuss one species from the Halonoproctidae trapdoor spiders, Ummidia solana sp. nov., and three Theraphosidae tarantulas included in different subfamilies, as follow: Euthycaelus cunampia sp. nov. (Schismatothelinae), Neischnocolus mecana sp. nov. (Theraphosinae), and Melloina pacifica sp. nov (Glabropelmatinae). All these new taxonomic records represent first reports of these genera for the region, which extends the range of geographical distribution of each of them. The results of this work constitute a contribution to the knowledge of the biological diversity of one of the areas with the greatest specific richness of species and endemism in Colombia.

Materials and methods
All specimens herein described were collected under Universidad's EAFIT General Collection Permit (Resolution 1566 of 24 December 2013; amended via Resolution 02493 of 31 December 2018); and deposited in the Arachnological Collection (Order Araneae) of the Instituto de Ciencias Naturales (ICN), Universidad Nacional de Colombia, Bogotá, Colombia, preserved in 75% ethanol. The specimens were collected during a biological expedition carried out in the Jardín Botánico del Pacífico (JBP), located in Bahía Solano, Chocó, Colombia (Fig. 2). The JBP has an area of 170 ha, extending from the Pacific coast to the Baudó mountain range (Fig. 2). This place is characterized by having an annual rainfall of more than 5000 mm, an average air temperature of 26 °C, and a relative humidity of 85% (Jardín Botánico del Pacífico 2014; Klinger Braham and Blandón Mosuera 2013). The field work took place during the days and nights from 10-25 February 2022.
Primary reproductive structures, palpal bulb and spermathecae, were removed for their description and photographic documentation. All photographs and descriptions of the copulatory bulb correspond to the left palp. Spermathecae were cleaned and cleared with lactic acid (85%) by immersion in a test tube and subjecting them to increased heat for short time intervals. Setae of the male tibia I and palpal tibia were removed in order to illustrate the tibial apophysis and nodules, respectively. Specimens and the structures removed were examined under a LEICA M205C stereo microscope. Photographs were taken with a stereo microscope ZEISS Stereo Discovery V12, then stacked with Helicon Focus 8.2.0 Mac OS (Helicon Soft Ltd. 2019) and processed with Adobe Photoshop CC 2022 (Adobe Inc. 2022).
All measurements are given in millimeters (mm). The total length given does not include the chelicerae or spinnerets. Eye sizes were measured as the maximum diameter in either a dorsal or frontal view and were taken with a digital micrometer. Body measurements were taken with a digital micrometer or a vernier caliper. The length and width of carapace, eye tubercle, labium and sternum are the maximum values obtained. Leg and palp measurements were taken in dorsal view along the central axis of the right-side limbs and were taken with a vernier caliper.
The general descriptive format follows Decae (2010) and Godwin and Bond (2021) for Ummidia and Raven (1985) and Bertani (2013) for theraphosids, with few modifications. No additional material was examined for the taxonomic analysis of any species. The diagnosis was made based on the original descriptions of its congeners and geographically related species. The diagnosis of Ummidia solana sp. nov. is based on Godwin and Bond (2021), and of Melloina pacifica is based on Bertani (2013) and Goloboff-Szumik and Ríos-Tamayo (2022). Setae on the ventral side of the tarsus in Ummidia and Melloina are considered as pseudoscopula, according to . Number and disposition of spines enumerated from the anterior third to the posterior third, modified from Petrunkevitch (1925). The palpal bulb terminology used in the text and figures follows Bertani (2000) and Guadanucci and Weinmman (2014) to Theraphosinae and Schismatothelinae, respectively. Urticating setae terminology follows Cooke et al. (1972) and Kaderka et al. (2019). For conservation of these new species, the same geographic coordinates of the JBP are recorded in the original description: 6.38, -77.40; specific geographic location data are recorded in the collection label for each of them. The distribution map was produced using QGIS 3.26.1 -Buenos Aires.  Etymology. The specific epithet solana is a noun in feminine refers to the municipality of Bahía Solano, one of the most beautiful places in the Colombian Pacific coast, recognized for having large and desolate beaches and landscapes of abundant vegetation. It is immersed in one of the world's biodiversity hotspots. It is also said that the word "solano" means "wind from where the sun rises".
Diagnosis. Ummidia solana sp. nov. can be differentiated from all geographically proximate species (see Godwin and Bond 2021) by the following combination of morphological features. Male: subcircular carapace, palpal bulb with thin and smoothly sinuous embolus, distally flattened ( Fig. 7A-D); tibia I with numerous spines, 14 prolateral and 40 retrolateral; tarsus IV with defined comb on the retrolateral face ( Fig. 6F) (males of U. quijichacaca and U. tibacuy unknown). Female: oval carapace, longer than wide, with strongly procurved fovea, wide and deep (Fig. 8A, B) (carapace longer than wide but angular in U. quijichacaca and wider than long and rounded in U. tibacuy, both with shallower fovea); basal segment of chelicerae with numerous lateral teeth (9-10) (4-6 in U. quijichacaca and U. tibacuy); maxillae with two sets (proximal and distal) of few cuspules Additionally, female and male (alive) with black carapace and legs, grayish abdomen, and male with reddish brown tarsi (Fig. 3A).
Legs I ( Fig. 6A-C) and II: lateral fields of short curvy spines on tarsus, metatarsus, tibia, and patella. Leg III (Fig. 6D, E): trochanter with blunt pointed apophysis on prolateral dorsal (Fig. 6D); femur swollen; patella strong, with prolateral field of eight short spines on half distal side; tibia short, strong saddle, flanked on either side by narrow membranous slits, with field of short spines on distal dorsal-prolateral side; metatarsus short, with dorsal field of four short spines on distal edge; tarsus short, with prolateral and retrolateral long spine field along full length of segment. Leg IV: retrolateral face of tarsus with defined comb over length of the segment (Fig. 6F).
Coloration. Living spider: carapace black, rugose; ocular area black, PME yellow; chelicerae basal segment, palp, and legs black; tarsi reddish brown; abdomen gray, with cream color spotted pattern. In alcohol: carapace black; sternum brown; labium and maxillae reddish brown; legs dark brown; abdomen gray with spotted pattern; genital area, book lung openings and spinnerets light yellow.
curved, deep, width 2.67; 5.32 from the anterior edge of carapace. Chelicerae basal segment: furrow with ca. ten prolateral / nine retrolateral teeth. Rastellum (Fig. 9A, B): present, formed by many stout short spines, the majority arranged in very developed prolateral process. Fang long. Maxillae (Fig. 9D   and four filiform trichobothria on distal edge; tarsi I-IV with 1-3 clavate trichobothria and few filiform trichobothria. All femora with wide membranous slits on distal side. All legs and palp with many spiniform setae (Fig. 10). All legs femora and patellae I and II without spines. Legs I (Fig. 10A, B) and II, and palp. Palp: femur with a wide row of fine spine-like setae (SLS) along 60% of the segment; patella with a low promedial lobe and four short and wide spines; tibia with a prolateral and retrolateral wide row of curved spines along full length of segment; metatarsus-tarsus with a prolateral and retrolateral wide row of curved spines along full length of segment. Femora I and II: with central rows of short fine SLS along full length of segment. Patellae I and II: with a low retromedial lobe, with three dorsal central rows of fine and short SLS along full length of segment, with some ventral long SLS. Tibiae I and II: with several row of dorsal SLS; tibia I with a wide prolateral and retrolateral row of curved spines along full length of segment; tibia II with a ventral row of lightly curved spines along full length of segment, with a prolateral row of short, curved spines along full length of segment. Metatarsi I and II: with dorsal SLS along full length of segment, and a prolateral and retrolateral row of curved spines along full length of segment. Tarsi I and II: with dorsal SLS and a prolateral and retrolateral row of short, curved spines. Leg III (Fig. 10C, D). Trochanter: with blunt pointed apophysis on prolateral dorsal (Fig. 10C). Femur: swollen, with dorsal and ventral rows of SLS. Patella: dorsal with a central row of SLS along full length of segment, with ca. 13 prodorsal short and strong spines in distal edge. Tibia (Fig. 10D): short, strong saddle, flanked on either side by narrow membranous slits on either side, field of short and fine spines in median side, field of short spines on distal prolateral and dorsal side, with a dorsal row of SLS along full length of segment. Metatarsus: with dorsal and prolateral strong spines, larger than tibiae spines, with a ventral row of strong spines on the distal edge of segment. Tarsus: with prolateral and retrolateral long spines and SLS along full length of the segment.
Leg IV. Trochanter and femur: unmodified. Patella: with a wide dorsal central row, prolateral fields of short spines, rise in size toward distal side. Tibia: swollen, dorsal and prolateral with a row of short and fine spines along full length of segment. Metatarsus and tarsus: prodorsal and retrodorsal with SLS along full length of segment, and with ventral long spines covering the totality of the tarsus and 80% of the metatarsus. Retrolateral face of tarsus with defined comb of long spinules over length of the segment (Fig. 10E).
Coloration. Living spider: carapace black, smooth, shiny, darker than male; ocular area black, PME yellow; chelicerae basal segment, palp, and legs black; abdomen dark gray, with cream color spotted pattern. In alcohol: carapace dark brown; legs and palp brown with darker overtones, mainly in femora and in the distal segments of all legs; sternum, labium, and maxillae brown; abdomen greyish brown with spotted pattern; genital area, book lung openings, and spinnerets light yellow.
Remarks. Ummidia solana sp. nov. is the third species described from the genus and the family Halonoproctidae for Colombia. Godwin and Bond (2021) previously described the species Ummidia quijichacaca and Ummidia tibacuy, both distributed in the center of the country, in the Eastern Cordillera of the Andean Region, and known only from female specimens. U. solana sp. nov. broadens the geographical distribution of the genus since it represents the first record from the Chocó Biogeographical Region. The male was captured walking at night while the female was captured inside her cave, also active at night. Her burrow was built on the ground under leaf litter. Etymology. The specific epithet pacifica is a noun in feminine refers to the Colombian Pacific region, where the species is distributed.
Legs pattern: IV>I>II>III. Lengths of legs and palpal segments on Table 4. Tarsal claws: STC long, with row of 2-4 small teeth, ITC absent on all legs. Claw tufts: weak, present in all tarsi. Tarsal scopulae: absent in all legs. Metatarsal scopulae: absent in all legs. Trichobothria: filiform of different sizes and clavate in all tarsi, I-IV with ca. 20 filiform, I-III with ca. ten clavate, IV with ca. seven clavate; filiform trichobothria also present in all metatarsi and tibia, including palpal tibia. Tarsus IV cracked at midpoint. Plumose setae on retrolateral face on femur IV: absent. Stridulatory bristles: absent. Body with strongly pilose setae. Book lung openings oval and sclerotized. Urticating setae: absent.
Coloration. In alcohol: as described in the male. Remarks. Melloina pacifica sp. nov. is the first species of the genus described for Colombia, although it is known that Melloina is distributed in different ecosystems, including cave environments Pérez-Miles et al. 2019). Males were captured actively walking at night and females were captured in shallow burrows, especially muddy ground. This record expands the geographical distribution of the genus, recorded previously only for Venezuela and Panama (WSC 2023). We confirmed the presence of pseudoscopulae in the anterior tarsi of males, as reported by . In the present work, M. pacifica sp. nov. is included within Theraphosidae according to phylogenetic analysis of Mori and Bertani (2020) and the preliminary results of Pérez-Miles et al. (2019). It should be noted, as mentioned by other authors, Melloina is a distinctive taxon since it is the only one with the exclusive combination of claw tufts and tarsal pseudoscopulae (only in males). Additionally, its taxonomic position is currently being widely debated (Raven 1985;Pérez-Miles et al. 2019;Mori and Bertani 2020;Goloboff-Szumik and Ríos-Tamayo 2022).

Subfamily Schismatothelinae Genus Euthycaelus Simon, 1889
Euthycaelus cunampia sp. nov. https://zoobank.org/6003756C-D948-4BFC-A0D2-9895FC2B98DF Figs 20-22; Table 5 Type material. Holotype ♂: Colombia, Chocó, Bahía Solano, Jardín Botánico del Pacífico, 6.  Etymology. The specific epithet cunampia is a patronym in honor of the family name of Don José and Don Antonio, members of the Emberá indigenous community, from Mecana, Chocó. Mr. José and Mr. Antonio abandoned their hunting traditions for their community to become touristic and academic guides for the JBP. We want to pay tribute to their community and to the JBP with this recognition.
Diagnosis. Males of Euthycaelus cunampia sp. nov. can be distinguished from all other Euthycaelus species by the following combination of morphological features: the shape of the palpal bulb (Fig. 22A-E), with subtegulum widely separated from tegulum, embolus elongated, broadened medially, and tip dorsoventrally flattened, with numerous prolateral keels near the apex and without denticles. Copulatory bulb of E. cunampia sp. nov. resembles males of E. quinteroi Gabriel & Sherwood, 2022, but differs by the wider embolus (Fig. 22C-E) with a curved inner edge (straight in E. quinteroi), and additionally by a higher number of maxillary cuspules (ca. 200 vs. 150) and labial cuspules (ca. 300 vs. 200). Additionally, Figure 20. Euthycaelus cunampia sp. nov., holotype male, habitus. males and females (alive) with carapace and legs black covered by light brown setae, and tibiae, metatarsi and tarsi covered with very light setae (Fig. 20).
Female. Unknown. Remarks. Euthycaelus cunampia sp. nov. represents the first published record of the genus and subfamily Schismatothelinae outside the Andean Region and the Eastern Cordillera for Colombia. This species constitutes the northernmost and westernmost record of the genus and subfamily for the country. Previously, the genus had a characteristic cis-Andean distribution over the Eastern Cordillera of Colombia and the Cordillera de Mérida in Venezuela (Valencia-Cuéllar et al. 2019). The geographic range of the genus Euthycaelus was recently extended with the publication of E. quinteroi from Panama, which is distributed in the same biogeographical region as E. cunampia sp. nov., in the Darien Gap, Chocó Biogeographical Region. This record extended the distribution of the genus to Central America. These latest records disrupt the distribution of the Euthycaelus, now being interpreted as a disjunct distribution, offering new evidence of historical connections between the Pacific humid forests and the Andean forests of the Eastern Cordillera. Etymology. The specific epithet mecana is a noun in apposition related to one of the townships of the municipality of Bahía Solano, where the JBP is located. The name of this small town is due to the fact that it is located on the Mecana riverside, with crystalline waters and abundant biodiversity. The JBP promotes the conservation, research, and recovery of the native biodiversity of this region. We would like to pay tribute to its community and the JBP with this recognition.

Subfamily
Diagnosis. Male of Neischnocolus mecana sp. nov. can be distinguished from the other Neischnocolus species by the following combination of morphological characters: shape of the palpal bulb piriform, with the tip of the embolus continuing the palpal organ axis (not perpendicular), well-developed prolateral (PS and PI) and apical (A) keels with non-serrated edge, PI discontinuous, absence of retrolateral keel (R), and without granulation or microspikes on embolus or tegulum (Fig. 25A-D); palpal tibia with two distal retrolateral processes (Fig. 25F). Female of Neischnocolus mecana sp. nov. differs from other Neischnocolus species in the spermatheca morphology consisting of a glandular and slightly sclerotized trapezoidal back-plate with small transverse keels, with two small asymmetrical tubiform seminal receptacles located on a small projected central portion of the atrium (Fig. 26F). Additionally, male and female have ventral coloration pattern (Figs 24B, E, 26B, E), and female has all body black color (Fig. 23B) (brown or reddish brown in the other species).
Coloration. Living spiders: body color brown, carapace and femora dark brown, legs brown, and abdomen reddish brown. Ventral abdomen with patterns of dark spots (Fig. 24B) and coxae with anterior-proximal white spots (Fig. 24E). In alcohol: reddish brown.
Legs pattern: IV>I>II>III. Lengths of legs and palpal segments on Table 7. Trichobothria: filiform and clavate; all tarsi with two irregular longitudinal rows of short claviform trichobothria. Tarsal claws: STC with a row of five or six small teeth, ITC absent. Scopulae: All tarsi 100% scopulate. Tarsal scopulae: tarsi I-III scopula entire, tarsus IV divided by a wide band of longer conical setae; all tarsal scopula with distal rhomboidal group of longer conical setae. Metatarsal Oca, and an anonymous reviewer for their valuable comments and corrections. Thanks to Mateo Giraldo for the photographs of Fig. 1.