On the cave spiders of Georgia with description of a new blind Centromerus (Arachnida: Araneae)

: A new species Centromerus georgicus sp. n. collected in a Georgian cave (Caucasus) is described based on male and female specimens, diagnosed, and illustrated. New records of some poorly known species ( Tegenaria pontica Haritonov, 1947, Dysdera anatoliae Deeleman-Reinhold, 1988 and Leptonetela caucasica Dunin 1990), as well as the description of the unknown female of L. caucasica are also presented.

The aim of the present study is to provide information on accumulating data on recently collected spiders in Georgian caves and description of a blind Centromerus species.

Material and methods
The studied material was collected by hand picking.Colouration is described from alcohol preserved specimens.Measurements of the legs were taken from the dorsal side.Total length of the body includes the chelicerae.All measurements are in mm.Specimens were examined and measured using a Wild M5A stereomicroscope.Digital images were taken with a Canon EOS1100 attached to a Carl Zeiss Amplival microscope and processed using Adobe Photoshop CS6 software.The specimens are preserved in 70-95% ethanol and deposited in Institute of Zoology, Tbilisi (IZISU), Natural History Museum Stuttgart (NHMS) and National Museum of Natural History, Sofia (NMNHS).The nomenclature follows the World Spider Catalog (World Spider Catalog, 2023) and the taxa are listed alphabetically.
Remarks.Known only from type locality (Phanagoria Cave) (Otto, 2022).Our specimen is either identical or closely related to T. pontica and corresponds with the description and single drawing published so far.Here we provide photographs of sternum and epigyne/vulva that correspond with the single figure in the description of the species (Figs 1-4).
Remarks.Known only from type locality (North Anatolia) (Deeleman & Reinhold, 1988).Our specimen is either identical or closely related to D. anatoliae and corresponds with the description and drawings published so far.Here we provide photographs of eyes and epigyne/vulva that correspond with the figures in the description of the species (Figs 5-8).
Remarks.The species was described by Dunin (1990) from a male, collected in detritus of beech forest in the North Caucasus.Marusik & Guseinov (2003) presented the description of a female of L. caucasica from Azerbaĳan with the remark, that the identification is very provisional and the single female may be preferable refer to the Turkish L. deltshevi (Brignoli, 1979) or to an undescribed species.The present material (male/female) is found in a cave but is identical both in habitus and structures of the palp and corresponds completely with the descriptions and all available drawings published so far .The collected undescribed female gives the possibility to ameliorate the description.
Genital area covered with short hairs, spermathecae slightly visible.Internal genitalia with a pair of spermathecae and sperm ducts, atrium fusiform (Fig. 12).(Dumitrescu & Georgescu, 1980;Deltshev, 1973Deltshev, , 1997;;Deltshev & Ćurčić, 2002); the terminal apophyses are similar but in C. georgicus sp.n. is the straightest, while in the other species it is more or less curved apically (Fig. 17) (Deltshev & Ćurčić, 2002); radical apophyses (I-II) are also similar but in C. bulgarianus the heel of R II is more pointed at the end, elliptical in C. georgicus sp.n. and more or less spherical in C. dacicus and C. serbicus (Figs 15-18) (Deltshev & Ćurčić, 2002); anteroproximal parts of the median membranes are similar butdiffer in details, with slightly toothed margin in C. georgicus sp.n. and C. bulgarianus and covered with small teeth along its entire length in C. dacicus and C. serbicus (Figs 16,18) (Deltshev & Ćurčić, 2002); females are almost indistinguishable but the spermathecae in C. georgicus sp.n. are the smallest than in the other species and the posterior median plate has a horizontal upper edge (Figs 19-22) (Deltshev & Ćurčić, 2002).

Linyphiidae
Etymology.The species name is derived from Georgia.
Colouration as in male.
Epigyne/Vulva : Anterior wall triangular, strongly wrinkled, covering a large epigynal cavity, ending with elongated truncated, squared tip.Distal part of scapus wide and rounded.Posterior median plate small and rectangular, with a triangular extension in the middle pointed to distal part, longer than wide.Spermathecae elongated comma-shaped.Copulatory ducts turning arcuate posteriorly and outward before returning to the middle part of the vulva, ending in copulatory openings in the distal part of the scapus.
Ecology. C. georgicus sp.n. inhabits the dark zone of the cave and can be regarded as a troglobite species (sensu Sket, 2008).
Distribution.Known only from the type locality in Caucasus Mts, Georgia (Fig. 23).
Remarks. C. georgicus sp.n., C. bulgarianus, C. dacicus and C. serbicus are closely allied and strictly vicariant species forming a superspecies.All these taxa are similar, they have limited ranges and probably, represent the descendants of a common ancestor; it is assumed that this ancestral form is no longer present in the epigean fauna and that it has been replaced by an extant Centromerus (Deltshev & Ćurčić, 1997