The spider genus Medionops Sánchez-Ruiz & Brescovit (Araneae: Caponiidae) in Colombia, with the description of four new species

Four new Colombian species of the spider genus Medionops Sánchez-Ruiz & Brescovit, 2017 are described and illustrated: M. carolinae sp. nov. (male and female) from Boyacá department, M. cauca sp. nov. (male) from Cauca department, M. luiscarlosi sp. nov. (male and female) from Caldas department and M. santarosa sp. nov. (male) from Risaralda department. Additionally, the distribution of the type species of M. blades Sánchez-Ruiz & Brescovit, 2017, previously known only from Bogotá, Cundinamarca department, is extended to several localities in the Boyacá department. An updated identifi cation key for all Medionops species is provided.


Introduction
The family Caponiidae S imon, 1890 is an unusual group of ground-wandering spiders, commonly found under rocks, tree trunks and leaf litter. Currently, it is represented by 19 genera and 127 species (World Spider Catalog 2021) occurring in America, Africa and Asia. The generic and specifi c diversity of the family is certainly great in the New World, where 108 species (15 genera) are known; while only 16 species (two genera) occur in Africa, a single monotypic genus is recorded in Iran and only two species (one genus) are known from Southeast Asia (World Spider Catalog 2021). The Caponiidae are divided into two subfamilies according to Petrunkevitch (1939): Nopinae, a subfamily exclusive to the New World and probably a monophyletic lineage, which includes those genera with tarsi divided by one or more adesmatic joints (Sánchez-Ruiz & Brescovit 2018), and Caponinae including all other nonnopine genera.
The Nopinae genus Medionops Sánchez-Ruiz & Brescovit, 2017 was proposed by Sánchez-Ruiz & Brescovit (2017) for seven species distributed in Trinidad, Panama, Colombia, Ecuador, Venezuela and Brazil. Members of this genus are characterized by having all legs with an elongated and dorsally refl exed unpaired claw, associated with a large and globose arolium (Sánchez-Ruiz & Brescovit 2017). Previous studies of pretarsal morphology in Medionops by Sánchez-Ruiz & Brescovit (2017; suggest that the genus is closely related to Nops MacLeay, 1839 and Nopsides Chamberlin, 1924, since some characteristics, such as the elongated unpaired claws and the presence of an arolium, are exclusive to these three genera. The discovery of Medionops by Sánchez-Ruiz & Brescovit (2017) was based on the examination of specimens gathered for the revision of Nops, published by Sánchez-Ruiz & Brescovit (2018). Specimens from 30 caponiid collections around the world were examined for the Nops revision, nine of which containing specimens later described as Medionops, many of them even identifi ed and labeled as Nops at that time.
Despite the fairly large sample of Caponiidae examined by Sánchez-Ruiz & Brescovit (2017, only a few dozen Colombian specimens came to light, none belonging to Colombian collections. As a result, no additional Colombian specimens were revised in either of these two studies. The scarce material reviewed from Colombia led to the fact that, till now, only one species of Nops (N. variabilis Keyserling, 1877) and one species of Medionops (M. blades Sánchez-Ruiz & Brescovit, 2017) were recorded from Colombia.
Recent examination of material from a Colombian arachnological collection (Instituto Alexander Von Humboldt), allowed the discovery of four undescribed Medionops species. These species are herein described and new distribution records for M. blades are given based on material also found in this arachnological collection. A detailed description of somatic and genitalic characteristics, images of the habitus, male palpal morphology and female genital organs, line drawings of the male copulatory bulbs and a distribution map for all Colombian species are provided. Additionally, an updated identifi cation key for all species of the genus is presented.

Material and methods
Morphological observations and illustrations were made using a Leica MC125 stereo microscope with a camera lucida. Multifocal images were taken with Leica MC-190 HD and Leica MC-170 HD digital cameras attached to Leica S8AP0 and Leica MC125 stereo microscopes, respectively, with extended focal range. All multifocal images were assembled using Helicon Focus Pro ver. 5.3.14. Measurements are provided in millimeters (mm) and were made using an ocular micrometer. Descriptions and measurements follow Sánchez-Ruiz & Brescovit (2017). Coloration patterns were described based on specimens preserved in 70-80% ethanol. All type specimens are in good conditions of preservation; the left male palp and female internal genitalia of holotypes and paratypes were dissected for detailed examination and documentation and stored in microvials inside their respective vials. The terminology for copulatory structures follows Sánchez-Ruiz et al. (2015). For M. blades, the female genitalia were dissected with fi ne forceps and scalpel and their soft tissues were digested for 24 hours within a solution of pancreatin following Álvarez-Padilla & Hormiga (2007). For the remaining species the female genitalia were extracted in the same way but digested with Ultrazime® contact lens cleaner enzyme (1 tablet / 5 ml distilled water).
The digital photos were edited using Adobe Photoshop® CS ver. 12.0 and fi gures were edited with Corel Draw® X7 ver. 17.1. Maps were prepared in QGIS (QGIS Development Team 2021). All locality coordinates were obtained from specimen labels and converted to the DMS format (degrees, minutes and seconds). Locality elevations refer to meters above sea level in all cases.

Institutional abbreviations
IAvH = Instituto Alexander Von Humboldt (curator: J.C. Neita), Bogotá, Colombia AMNH = American Museum of Natural History (curator: L. Prendini), New York, USA Abbreviations for morphological terms used in the fi gures ap = anterior plate b = area below genital opening e = embolus ess = external sclerotization around spiracles go = genital opening mc = median concavity on receptaculum re = receptaculum t = tegulum ue = uterus externus  10. Crista short but noticeable, not reaching one fourth of metatarsal length; body more than 4.5 mm total length; males with embolus length more than 3 × the maximum diameter of the tegulum (

Natural history
The holotype was found in the Andean moorland complex of the eastern hills of Colombia ( Fig. 8A-B) which is predominantly populated by plant species such as Espeletia grandifl ora Humb. & Bonpl. and Cupressus sp.

Variation
Males from the Boyacá department population (Fig. 1A-B) have the embolus tip somewhat more curved than those from Cundinamarca department (see images from types in Sánchez-Ruiz & Brescovit 2017: fi gs 2h, 6d). Females from the Boyacá population (Fig. 1G) have a narrower and more sclerotized area under the genital opening than those from the Cundinamarca population.

Distribution
Known from Cundinamarca and Boyacá in Colombia (Fig. 6).  differ from those of M. blades by the narrow, triangular area below the genital opening ( Fig. 2G) (wider and concave in M. blades, Fig. 1G).

Etymology
The specifi c name is a patronym in honor of Carolina Gomez, director of the collections of the Institute Alexander Von Humboldt, Bogotá, Colombia. COLORATION. Carapace, chelicerae, sternum, labium and endites reddish ( Fig. 2A-B). Palps and legs light orange. Abdomen dorsally dark gray with dorsal pattern formed by fi ve wide light chevron stripes, medially joined by thin longitudinal band; ventrally whitish gray ( Fig. 2A-B).

Natural history
All types were collected with pitfall traps baited with human excrement, used to collect dung beetles and ants, mainly in frailejón plants (Espeletia grandifl ora Humb. & Bonpl.) and grassland. Specimens belonging to ant-eating spiders such as Zodariidae Thorell, 1881 were collected together with Medionops in large numbers, probably due to the high availability of prey. Aspects on the natural history of Nopinae spiders are poorly known and only a few studies on the trophic specialization of Nops have been done (see  García et al. 2018;Teruel & Sánchez-Ruiz 2000). These studies highlight the remarkable preference of some nopine species for feeding on arachnids (little scorpions and other spiders). Although no detailed studies have been conducted, the adhesive membranous structures (crista and gladius) on the fi rst two pairs of nopine legs are pobably involved in the prey capture process.

Remarks
The holotype was found in a high Andean humid forest (Fig. 8C-D) and the female paratype was found in a protected area (Sanctuary of Flora and Fauna Iguaque) where human intervention is limited (Fig. 8E-F). The record of this female specimen is separated by only 24 km from the type locality and 8 km from the most distant examined specimen located outside the type locality. The height above sea level between type and female localities hardly differs by about 300 m and even the environments are very similar in both locations (Fig 8C-F). We tentatively matched this female with males from the type locality by similarities in the coloration pattern, but confi rmation of this association will be possible only when more samples come to light. We believe that proposing this doubtful association is preferable to making available a possibly unnecessary specifi c name.
LEGS AND PALPS. Crista unnoticeable; gladius with common nopine shape. Palp with spherical oval tegulum and slightly sinuous embolus longer than cymbium and strongly angled at base (Figs 3C-D, 7C), with acuminate tip and rounded opening.

Distribution
Known only from the type locality in Colombia (Fig. 6).

Diagnosis
Males resemble those of M. santarosa sp. nov. in having a similar copulatory bulb shape, but can be distinguished by the embolus length more than 3 × the maximum tegular width, with pointed tip (Figs 4E-F, 7D) (shorter, with truncated tip in M. santarosa sp. nov., Figs 5C-D, 7E). Females are distinguished from those of all other species by the fl at median concavity on the receptaculum (Fig. 4H).

Holotype
LEGS AND PALPS. Crista unnoticeable; gladius with common nopine shape. Palps with spherical tegulum with small projection on posterior side, embolus length more than 3 × the maximum width of tegulum, with pointed tip (Figs 4E-F, 7D), tip of embolus slightly curved and sharp, with small opening.
LEGS AND PALPS. Crista and gladius as in male. External genitalia with white triangular area below genital opening (Fig. 4G), internal genitalia with fl at median concavity on receptaculum (Fig. 4H).

Distribution
Known from two localities in Caldas department, Colombia (Fig. 6).

Remark
All type specimens were collected with pitfall traps.
LEGS AND PALPS. Crista unnoticeable; gladius with the common nopine shape. Palp with spherical tegulum; embolus length less than 3 × the maximum width of the tegulum, with truncated tip (Figs 5C-D, 7E) and rounded opening.

Female
Unknown.

Distribution
Known only from the type locality in Colombia (Fig. 6).

Discussion
The present study increases from one to fi ve the number of Colombian Medionops species recorded. All these species are known from only a few localities within the country. Among the nopines, Medionops is one of the few genera presenting all three membranous structures of the pretarsal morphology (crista, gladius and arolium) that appear in members of this subfamily (Sánchez-Ruiz & Brescovit 2018). These three membranous structures have been known since Keyserling (1877), who was the fi rst to detect them; however their characteristics remained little studied until Sánchez-Ruiz & Brescovit (2017) standardized their terminologies. The arolium is present only in Nops, Nopsides and Medionops, while the adhesive structures crista and gladius are more common within the nopines. Nyetnops is the only nopine lineage that does not have any of these three structures (Platnick & Lise 2007). The arolium is evolutionarily related to the elongated unpaired claw, since the unpaired claws became elongated to shelter an enlarged arolium (Sánchez-Ruiz & Brescovit 2018). However, Nops species are characterized by a very short or reduced arolium, yet the anterior unpaired claws are elongated in all species, and only in a few species are the posterior unpaired claws not elongated. Conversely, Medionops and Nopsides are characterized by a large arolium and an elongated unpaired claw (Sánchez-Ruiz & Brescovit 2018). Generally, the gladius is homogeneous in size and shape in all lineages that present this structure. Within the nopines with gladius, Medionops is the only genus with at least one species lacking this structure (M. murici Sánchez-Ruiz & Brescovit, 2017); coincidentally, the crista is also absent in this Brazilian species. This would be the fi rst documented instance of gladius and crista loss within a nopine genus. The crista is also fairly homogeneous among genera, but Medionops again diverges from that pattern, presenting diverse conformations of crista shape and size across species. This genus is generally characterized by a very short crista, but it's unnoticeable in M. ramirezi Sánchez-Ruiz & Brescovit 2017 and completely absent   (2018), the crista, gladius and arolium seem to be membranous leg structures that could appear and disappear more easily than other structures. Although the presence and shape of these membranous structures may vary interspecifi cally in Medionops, intraspecifi c variation is not common in the genus. As far as we know, detectable morphological variation between populations is present only in M. blades, specifi cally in the male palpal morphology and the female external genitalia. The populations from Boyacá department have the embolus tip somewhat more curved than those from Cundinamarca department, where the holotype comes from. In females, the area under the genital opening is narrower and more sclerotized in the populations from Boyacá than in those from Cundinamarca department, but the internal receptaculum is very similar in both populations.
On the other hand, M. blades appears to be close to M. carolinae sp. nov. and M. cesari (Dupérré, 2014). The males of these three species have a similar copulatory bulb shape with an oval tegulum and an elongated embolus curved at the tip. However, these species are distinguished by some diagnostic characteristics that suggest a close relationship between the members of M. carolinae sp. nov. and M. cesari. Both species have the tegulum ⅓ as long as the cymbium length (larger in M. blades) and an accentuated curvature at the embolus tip (straighter in M. blades). However, the morphology of the emboli tips, both in M. carolinae sp. nov. and in the two known populations of M. blades, is quite similar. In that regard, the several blade-shaped embolar projections, which were diagnostic for members of M. blades, are also present in M. carolinae sp. nov.
Considering the variations of both known populations of M. blades and their similarities with M. carolinae sp. nov. and M. cesari, the hypothesis that M. blades represents a complex of closely related species cannot be dismissed with the available evidence. We hope soon to be able to obtain more specimens from other localities from Colombia and Ecuador to test this hypothesis with both molecular and additional morphological studies.