A new spider species, Heser stoevi sp. nov., from Turkmenistan (Araneae: Gnaphosidae)

Abstract Background The genus Heser (Araneae, Gnaphosidae) belongs to the Zelotes group, and is currently known to comprise 10 species distributed in Africa, Asia, Europe and North America. The type species is Heser malefactor Tuneva, 2004 from Kazakhstan. New information A new spider species, Heser stoevi sp. nov. (male and female) found in Koytendag Mountains, southeastern Turkmenistan is described and illustrated. It is morphologically close to H. aradensis (Levy, 1998) from Israel but can be readily distinguished by the longer embolus, the smaller and flattened conductor, the lack of retrolateral tibial apophysis, all this coupled with very distinctive female copulatory organs. The new species was found under stones in arid grassland habitats.


Introduction
The genus Heser (Araneae, Gnaphosidae) belongs to the Zelotes group, which comprises genera of small to medium-sized spiders (typical size ranges from 2 to 10 mm) with preening distal combs on metatarsi III and IV (Murphy 2008). This character is not possessed by any other gnaphosid group. The genus is delimited by Tuneva (2004) with the description of the type species Heser malefactor Tuneva, 2004 from Kazakhstan. In this work, she proposed also two new combinations, both ex. Zelotes -H. aradensis (Levy, 1998) from Israel, andH. infumatus (O. Pickard-Cambridge, 1872) from Egypt, Israel and Tanzania. Later, Bosselaers (2010) and Senglet (2012)

Materials and methods
The specimens were hand-collected under stones. Coloration is described from alcoholpreserved specimens. Male palps and female genitalia were examined and illustrated after dissection from spiders' bodies. All photos were taken with the aid of Panasonic DMC-FS62 digital camera mounted on Wild M5A stereomicroscope. Measurements of the legs are taken from the dorsal side. Total length of the body includes the chelicerae. All measurements are in mm. Abbreviations: AME -anterior median eyes; ALE -anterior lateral eyes; E -embolus; C -conductor; MA -median apophysis; PLE -posterior lateral eyes; PME -posterior median eyes; SD -sperm duct; ST -spermatheca. The type specimens are deposited in the National Museum of Natural History (NMNHS), Sofia, Bulgaria.
Material used for comparison: Heser aradensis (Levy, 1998) Carapace uniformly brown, with a fovea in the posterior half (Fig. 1a, c). All eyes subequal, AME circular, separated from each other by their own diameter, ALE oval, touching AME. PME oval to subtriangular, touching, larger than AME. PLE oval, slightly smaller than ALE, separated from PME by more of one PLE diameter. Clypeus vertical, large one diameter of AME. Chelicerae brown, with a few scattered thin setae on anterior surface, promarginal rim with three very small teeth spaced closely to fang base, retromarginal rim spineless. Sternum smooth, yellow brown, shield-shaped with a thin border (Fig. 1b). Abdomen grey with frontal row of curved hairs and a scutum covering about 10% of abdominal dorsal surface area (Fig. 1a, c). Legs yellowish to yellow-brown (Fig. 1a, c), leg formula 4123, measurements as in Table 1. Male palp (Fig. 2a, b, c, Fig. 5a, c, e): Distinctive retrolateral tibial apophysis is not presented, hence distal part of tibia retrolateral is strongly chitinized and dark colored. The embolus is slender, basally prolaterally inserted, extends across the broad and flat conductor (sensu Bosselaers 2010), circling more than half of the tegulum. Median apophysis large, hook-shaped.

Diagnosis
The somatic characters of the new species correspond to those of the genus Heser, but the genitalia are distinctive and separate well the new species from all other congeners. Morphologically, the new species resembles H. aradensis (Fig. 1b, d) but the male has longer embolus, and smaller and flattened conductor (sensu Bosselaers 2010), as well as lacks distinctive retrolateral tibial apophysis (Fig. 2a,

Etymology
Named in honour of the Bulgarian zoologist Pavel Stoev, who collected the species; name in genitive case.

Distribution
The species is hitherto known only from two closely situated localities in the western slope of Koytentag Mts, southeastern Turkmenistan (Fig. 7). a b c d Figure 6.