Philodromus musteri spec. nov. of the Philodromus aureolus group from Turkey (Araneae: Philodromidae)

Abstract. Philodromus musteri spec. nov., a member of the Philodromus aureolus group from the Mediterranean coast of south-west Turkey, is described from a male specimen. Photos, drawings, diagnosis and a complement to the determination key are provided.

The philodromid fauna of Turkey includes a fairly large number of species (i.e., 37 species according to Logunov & Kunt 2010; 38 species according to Danışman et al. 2019) but is still incom pletely known. So far, 11 members of the Philodromus aureolus group -among the 15 known from the Mediterranean region (Muster & Thaler 2004) -have been recorded from Turkey (Danışman et al. 2019). Philodromus musteri spec. nov. thus constitutes the 12th species of the aureolus group for Turkey and the 16th member of the group in the Mediterranean region.

Material and methods
The male specimen described below was caught alive, imma ture and then raised in captivity to adulthood (molted on 21. Apr. and 19. May 2019). A second specimen, male, immature was also bred in captivity but without reaching the last moult.
For measurements, an eyepiece micrometer was used; all measurements are in mm. The measurement of the leg arti cles was done in dorsal view. Geographic coordinates are pre sented in the WGS 84 system; they were obtained using a smartphone's GPS. Terminology of the genital organs follows Muster & Thaler (2004).

Determination key
The determination key for males to species of the Philodromus aureolus group in the Mediterranean region, proposed by Muster & Thaler (2004), can be adopted in the number 5 and can be complemented between the numbers 12 and 13 as fol lows to include the new species and Philodromus azcursor from Azerbaijan. Remarks: amended or added text is shown in bold; P. bonneti was not included (see Muster & Thaler 2004).

5
Embolus long, originating clearly at proximal half of te gulum (

Discussion
Philodromus musteri spec. nov. has the characters distinguishing members of the Philodromus aureolus group (Dondale & Redner 1976: 129, Wunderlich 2012: 37, Fig. 22, Lecigne et al. 2019. I), particularly the genital characters. Distinctive is a stiff membrane (conductor) on which the embolus of the male rests and a stout and curved seta on the tegulum (the intertegular re ticulanum according to Braun 1965) (Dondale & Redner 1976). Wunderlich (2012) also mentioned an asymmetrical cymbium widened prolaterally, a palpal tibia with three apophyses and most often the base of the embolus thickened (inconspicuous for the new species). The Philodromus aureolus group is rich in species. Since its creation by Chyzer & Kulczyński (1891), many species and subspecies related to this group have been described while introducing at the same time some taxonomic con fusion. Thereafter, further works, notably Kubcová (2004), have clarified the situation. Furthermore, Muster & Tha ler (2004) updated the list of the species of the P. aureolus group known from the western Palaearctic region and the Mediterranean, and at the same time specified the nature of genitalia characters as criteria for differentiation. These works enabled the study of the specimen found at Tekirova.
The discovery of this new species can probably be exp lained by the absence or lack of surveys on the site but also in this area of the province of Antalya. However, it can not be excluded that the species has already formerly been collected and misidentified. It presents similarities with respect to genital structure with P. praedatus O. Pickard Cambridge, 1871 but is rather closely related to P. lunatus and P. buchari, even if none of these two species shows the same combination (see Diagnosis). Distribution. Philodromus lunatus appears to be mainly spread out in the eastern Mediterranean (Muster & Thaler 2004) while P. buchari and P. praedatus show a much wider range; P. buchari occurs in Europe as far as Turkey, P. praedatus is widespread in the western Palaearctic region and occurs in the Mediterranean area as far as Azerbaijan. However, the lat ter has not been yet mentioned from Turkey (Danışman et al. 2019). Fig. 4 shows the distribution in Turkey, by provinces, of two of these three closely related species.
Four other immature/subadult specimens of the P. aureolus group were collected during the survey, two of which probably represented the new species. No other species of this group has been recorded within the same site or in its vicinity. Nevertheless, it is very likely, in view of its distri bution, that P. lunatus may also be present there (see Fig. 4). Other species of the Philodromus aureolus group. As evi dence that the knowledge of this group is still incomplete, P. azcursor, another species close to P. buchari and P. cespitum (Walckenaer, 1802), has been recently described from Azerbaijan (Logunov & Huseynov 2008). It has been added to the updated determination key (see above).  Karol, 1968 is a reportedly endemic species known so far only from northwest Turkey (Bursa) and only from the male. It was described by Karol (1968) as belonging to the Philodromus aureolus group and recognized as such by Muster & Thaler (2004), but could not be tra ced at the Paris museum. The authors state that this species resembles P. lunatus with respect to characters of the male palpal organ. However, several details actually suggest that some structures have been schematized in the figures, i.e. simple, conical shape of several apophyses (RTA, ITA), un figured descending part of sperm duct loop, schematic con ductor contour and the unfigured intertegular reticulanum, at least in retrolateral view.