A survey of the East Palaearctic Lycosidae (Araneae). 9. Genus Xerolycosa Dahl, 1908 (Evippinae)

Abstract Three species of Xerolycosa: Xerolycosa nemoralis (Westring, 1861), Xerolycosa miniata (C.L. Koch, 1834) and Xerolycosa mongolica (Schenkel, 1963), occurring in the Palaearctic Region are surveyed, illustrated and redescribed. Arctosa mongolica Schenkel, 1963 is removed from synonymy with Xerolycosa nemoralis and transferred to Xerolycosa, and the new combination Xerolycosa mongolica (Schenkel, 1963) comb. n. is established. One new synonymy, Xerolycosa undulata Chen, Song et Kim, 1998 syn. n. from Heilongjiang = Xerolycosa mongolica (Schenkel, 1963), is proposed. In addition, one more new combination is established, Trochosa pelengena (Roewer, 1960) comb. n., ex Xerolycosa.


Introduction
This paper is the first in a series of reviews of the Palaearctic Evippinae Zyuzin, 1985. Evippinae is a relatively small subfamily of wolf spiders restricted to Africa and the Pal-aearctic Region. Only four species belonging to two genera have been recorded from Europe, Xerolycosa nemoralis (Westring, 1861) and X. miniata (C.L. Koch, 1834) (both occur throughout Europe), Evippa eltonica Dunin, 1994 (easternmost Europe, only a few dozen kms from Asia) (Helsdingen 2010) and "Evippa" apsheronica Marusik, Guseinov &Koponen, 2003 (Ponomarjov andTsvetkov 2004;Kovblyuk 2007). Most Evippinae species in the Palaearctic Region have been reported and described from Central Asia and China (cf. Platnick 2011). Xerolycosa Dahl, 1908 was assigned to the Evippinae by Zyuzin (1985). It is the most widespread genus in the subfamily, ranging from the Iberian Peninsula to Kamchatka. The genus currently includes five species (Platnick 2011), three of which are restricted to the Palaearctic Region and two occur in the Afrotropical Region. The purpose of this paper is to provide a review of this small genus.

Material and methods
Specimens were photographed using either a JEOL JSM-5200 scanning electron microscope or an Olympus Camedia E-520 camera attached to an Olympus SZX16 stereomicroscope at the Zoological Museum, University of Turku. Digital images were montaged using a "CombineZM" image stacking software. Photographs were taken in dishes of different sizes with paraffin at the bottom. Different sized holes were made in the bottom to keep the specimens in the correct position. Figures had been made previously and in some cases we were unable to generate scale bars for the digital photographs. All measurements are given in mm. Drawings we made either by using a grid method with a MBS-9 stereomicroscope or a Leitz stereomicroscope with a camera lucida. The bleached epigyne of the holotype female was temporarily coloured with Chlorazol Black. Epigynes were macerated using KOH solution. In the tables of leg spination, apical and dorsal spine data are omitted.
Terminology of the copulatory organs follows Zyuzin (1985Zyuzin ( , 1993. Abbreviations used in the text: AME, ALE, PME, PLE -anterior median, anterior lateral, posterior median and posterior lateral eyes respectively; pv -proventral; rvretroventral; v -ventral; p -prolateral; r -retrolateral. Acronyms: triangle-shaped hoods of the apical pocket) and seems to belong to Trochosa. Therefore, we propose the new combination: Trochosa pelengena (Roewer, 1960) comb. n. Xerolycosa sansibarina, known from the male sex only, has a carapace and abdominal pattern very different from Evippinae species, and the palp has a distinctly different conformation, typical for the Lycosinae (tegular apophysis stretching horizontally, tip of embolus visible and resting horizontally in a tegular depression). However, we refrain from suggesting a new combination because its generic affinities are currently unclear.

IBPN
Because of the burrowing behaviour in X. mongolica (Schenkel, 1963), believed to be absent in the other species, we first followed A.A. Zyuzin's (personal communication) opinion that it may belong to a separate genus. However, females of X. nemoralis are known to excavate shallow depressions in soil (Smola 2007). In addition to behaviour, X. mongolica has widely spaced posterior median eyes (one diameter apart) in contrast to the type species, X. nemoralis, and X. miniata (less than one diameter apart). Study of the male palp and the leg spination revealed no differences between X. mongolica and the other species.

species separation
Xerolycosa species can be distinguished by the shape of the copulatory organs. In addition X. mongolica can be recognized by the variegated (spotty) pattern of the carapace and abdomen, and by lacking a light median band. The spination of leg I may help to distinguish males of X. mongolica, and females of all species.
The male palps in all three species are rather similar in general appearance. The species can be relatively easy recognized in retrolateral view by the profile of the tegular apophysis 25,27,29) and by the shape of the embolic region following dissection, notably the course and length of the embolus, and the seminal duct position (Figs 26,28,30). The males of X. miniata and X. nemoralis have the same spination pattern on leg I (Table 1), but the females have different leg spine formulae ( Table  2). The epigynes in the three species are very similar and can be distinguished by the shape of the septum and the "windows" (Figs 31,33,35,37,39,41). Additional differences can be found in the spermathecae (Figs 32,36,40,34,38,42).   X. nemoralis by the shorter seminal duct, a bent free part of the embolus and a bent tip, a rounded (not pointed) process of the tegular apophysis, basal part higher than apical (equal in X. nemoralis), and the lack of a tegular ridge. Females can be distinguished by the proportions of the epigyne (windows longer than wide, whereas in X. nemoralis they are wider than long). Description. Male. Total length 5.0 (4.7-6.2). Carapace: 2.85 (2.52-3.09) long, 2.1 (1.79-2.22) wide. Carapace length/femur IV ratio 1.2. Habitus and pattern as in Fig. 6; carapace with wide white median band and marginal light stripes.

Key to the Palaearctic
Spination of legs: Palp as in Figs 22, 27-28, cymbial spines poorly distinct, upper part of tegular apophysis with claw-like outgrowth; embolus relatively thin, following an oval course, tip modified.
Distribution. X. miniata has a Euro-Mongolian boreo-nemoral range (Marusik et al., 2000) and is known from Portugal to Tuva, north to central Finland and north Ural, and south to Azerbaijan and north-western Mongolia.
X. undulata was described on the basis of the holotype male from Heilongjiang, not far from Tsitsikar. According to the text (Chen et al. 1999), the type was deposited in the Institute of Zoology in Beijing. However, the type was not found in the collections (Li, personal communication). Comparison of our figures of the male palp of X. mongolica and figures of X. undulata provided by Chen et al. (1998) leaves no doubts that these two names should be synonymized. It is worth mentioning, that when X. undulata was described the male of X. mongolica was unknown.
Epigyne as in Figs 35-38, septum almost triangular in shape, upper margins of windows inclined.
was synonymized with X. nemoralis by Yu & Song (1988) without examination of the female holotype. Study of the holotype and comparison with European and Siberian specimens of X. nemoralis revealed clear differences in pattern, spination and copulatory organs and therefore we remove X. mongolica from synonymy and establish a new combination.
Biology. X. mongolica females make burrows in the ground in places with sparse steppic vegetation. The burrows are relatively deep 7-10.5 cm and 4-6 mm in diameter (Logunov, personal communication). Apparently males do not construct burrows.
These observations were first made by Dmitri Logunov in Tuva. Subsequently we (Koponen and Marusik) witnessed this behaviour. It is worth mentioning that X. mongolica seems to be the smallest burrowing wolf spider (Logunov, personal communication).
Epigyne as in Figs 39-42, windows wider than high, septum with rounded sides. Comments. Judging from the figures, the record of X. nemoralis by Yin et al. (1997: f. 3a-d) from China refers to another species and even a different genus. Distribution. X. nemoralis has a trans-Palaearctic boreo-nemoral range (Marusik et al. 2000) and occurs from the Iberian Peninsula to Kamchatka and the North Kuril Islands, north to the Polar Circle in Lapland and to central Yakutia, south to Azerbaijan and Honshu.