A new species of Euscorpius Thorell, 1876 (Scorpiones, Euscorpiidae) from Marmara Region of Turkey

Abstract A new species of the genus Euscorpius Thorell, 1876 is described based on specimens collected from Bursa Province, in Marmara Region of Turkey. It is characterized by a mesotrichous trichobothrial pattern (Pv= 8, et= 6, em=4, eb= 4), medium size and light coloration. Euscorpius (Euscorpius) rahsenae sp. n. is the second species of the subgenus Euscorpius recognizedin Turkey.


Introduction
The genus Euscorpius Thorell, 1876 is one of the most studied taxa of scorpions, however, because of its complexity, its taxonomy continuously changes and is not completely clear, especially in the Balkans, Turkey and in Western Europe. The Euscorpius populations of Turkey have been poorly studied, and only three valid species are recognized: E. (Polytrichobothrius) italicus (Herbst, 1800), E. (Alpiscorpius) mingrelicus (Kessler, 1874) and E. (Euscorpius) avcii Tropea et al., 2012. E. mingrelicus, which is a spe-Turkey; AZM: Alaşehir Zoological Museum, Celal Bayar University, Manisa, Turkey; FKCP: František Kovařík Collection, Praha, Czech Republic.
The trichobothrial notations follow Vachon (1974). The morphological measurements are given in millimeters (mm) following Stahnke (1970). The morphological nomenclature follows Stahnke (1970), Hjelle (1990) and Sissom (1990); the chela carinae and denticle configuration follows Soleglad and Sissom (2001) and sternum terminology follows Soleglad and Fet (2003); description and terminology of hemispermatophore follows Soleglad and Sissom (2001) and Fet and Soleglad (2002).  bothria on the pedipalp manus ventral surface is 4 (3 V + Et 1); the number of trichobothria on the pedipalp patella ventral surface is 8 (in 87.29% of examined pedipalps); the number of trichobothria on pedipalp patella external surface is: eb = 4, eba = 4, esb = 2, em = 4, est = 4, et = 6 ( in 77.96% of examined pedipalps). The pectinal teeth count is 9 (in 80.55% of examined pectines) in males, 7 (in 68.29% of examined pectines) in females. The telson vesicle in males is considerably more swollen than in females: average L/H ratio of the vesicle is 2.07 in male and 2.30 in females. Chela with a notch on fixed finger and scalloping of the movable finger in adult males, obsolete in females. Dorsal patellar spur well developed. Average L/W ratio of the chela is 2.35 in males and 2.48 in females. Average length/posterior width ratio of the carapace is 0.98. All carinae on pedipalps are strongly distinct and dark, in contrast with clear color of tegument. Average value of the length from center median eyes to anterior margin of the carapace is 42.47% of the carapace length. Average value of the length from center median eyes to posterior margin of the carapace is 57.53% of the carapace length.

Taxonomy
Description of the holotype male. Coloration: Very light brownish with carapace and pedipalps little darker, legs, telson and chelicerae are lighter. The carinae are dark, distinctly brownish-blackish, especially on pedipalps. Dark lines in the external or distal part of the coxa and sternum. Granulometry on the femora of the legs, especially ventrally, dark. The sternites, pectines and genital operculum are very light brownish-white.
Carapace: Length 4.11 mm; posterior width 4.14. Very finely granulated. Distance from the center of the median eyes to the anterior margin of the carapace is equivalent to 42.33% of the prosoma; the length from the center of the median eyes to the posterior margin of the carapace is equivalent to 57.67% of the prosoma.
Mesosoma: Tergites very finely granulated; sternites finely punctate. The area of overlap between the sternites is lighter in color. Pectinal teeth count is 9-9. The spiracles are very small, oval-shaped and it is inclined about 45° downwards towards outside.
Metasoma: Medium size with respect to body length. Dorsal carinae from segment I-IV are granulated, exhibiting dark granules, obsolete on the segment V; ventromedian carinae from segment I-IV absent; ventromedian carinae on segment V are formed by fine granules; ventrolateral carinae on segment I absent, on segments II and III smooth, on segment IV is formed by small dark granules, on segment V is formed by dark granules; all intercarinal spaces are finely granulated.
Pedipalp: Coxa and trochanter with strong granulation. Femur: dorsal internal carinae tuberculate; dorsal external carinae formed by tubercles, slightly serrulated; intercarinal spaces granulated; external median carinae serrulate, anterior median formed by hardly conical tubercle. Patella length 3.54; patella width 1.38; dorsal internal carinae crenulate to tuberculate; dorsal external carinae low, from rough to crenulate; Ventral external carinae crenulate; ventral internal carinae from serrulate to tuberculate; dorsal intercarinal tegument with granules of increased size from proximal to distal area; ventral intercarinal tegument from smooth to minutely granulate with a few bigger granules near to ventral internal carinae; internal intercarinal tegument uniformly finely granulate. Dorsal patellar spur averagely developed (Fig. 1E). Chelal carina D 1 is distinctly strong, dark and from smooth to rough; D 4 is rough with a few low granules in proximal area; V 1 is distinctly strong, from rough to crenulate and dark; V 3 dark on ¾ of length, mostly smooth with a few scattered minuscule granules; external carina rough and dark; intercarinal tegument from smooth to rough except between carinae D 4 and V 3 , granulate. Movable finger dentition: MD form a straight line of very small denticles closely spaced with a DD on the distal tip; OD formed of 7 denticles on movable finger and 6 denticles on fixed finger, immediately outside of MD, their size increases progressively but the terminal denticle is not very pronounced; ID formed of 7 denticles on movable finger and 6 denticles on fixed fin- ger, spaced from MD, their size increases progressively but the terminal denticle is not very pronounced; IAD on both movable and fixed finger formed of 4 small denticles; L/W ratio of the chela 2.35   Legs: legs with two pedal spurs. Tarsal ventral row with 10-12 stout spinules (including the ventral distal spinule pair); 3 flanking pairs of tarsal setae adjacent to the ventral spinules row. Basitarsus with 6-7 prolateral stout spinules on leg pair I; 4-3 prolateral stout spinules on leg pair II; absent on leg pair III and IV. Dark granulation present above leg femora, mostly ventrally; on the dorsal leg femora I it is weakly marked and of lighter color.
Chelicerae: smooth, without marbling, with darker teeth; the dorsal distal tooth is smaller than the ventral distal tooth; ventral edge is smooth with brush-like setae on the inner part; dorsal edge has five teeth: one distal, two small subdistal, one big median and a small basal; fixed finger has four teeth: one distal, one subdistal, one median and one basal; the median and the basal are in a fork arrangement; the internal edge has brush-like setae.

Discussion and comparison
The only valid species belonging to the subgenus Euscorpius in Turkey is E. avcii. This species was recently described from Dilek Peninsula as an oligotrichous, small Euscorpius, with a length of 24-28 mm, light brown to brown-reddish colored with the carapace and pedipalps darker and legs and telson lighter (Tropea et al. 2012). It is possible to differentiate this species from E. rahsenae sp. n. as follows: the color of E. avcii is reddish brown while E. rahsenae sp. n. is very light brown-ivory with a strong contrast dark color of the carinae; E. avcii is on average smaller than E. rahsenae sp. n. (24-28 cm and 27-34 mm respectively); the pectinal teeth count in E. avcii is 7 in females and 8 in males while in E. rahsenae sp. n. is usually 7 in females and 9 in males; Pv count is usually 7 in E. avcii and 8 in E. rahsenae sp. n.; Pe-et series is generally 5 in E. avcii and 6 in E. rahsenae sp. n.; hemispermatophore exhibiting 6 delicate spines in E. avcii, 8-12 in E. rahsenae sp. n.
The other forms of the subgenus Euscorpius are obviously different species and geographically distant. Below, we compare E. rahsenae sp. n. to some other forms present in the Aegean area: E. sicanus (C. L. Koch, 1837), E. c. candiota Birula, 1903, E. c. scaber Birula, 1900, E. c. ossae Di Caporiacco, 1950and E. c. aegaeus Di Caporiacco, 1950 E. sicanus complex is widespread in mainland Greece and some Aegean islands , and can be easily distinguished from E. rahsenae sp. n. by the trichobothrial series eb = 5 in E. sicanus complex and eb = 4 in E. rahsenae sp. n.
E. c. candiota is a light colored species, described from Crete. It can be distinguished by the E. rahsenae sp. n. by the higher number of trichobothria and pectinal teeth; Pv = 9/10 (usually 10), Pe-et = 6/8 (generally 7) and pectinal teeth count 9 to 10 in males (generally 10) and 7 to 8 in females, compared to Pv = 8, Pe-et = 6 and pectinal teeth count 9 in males and 7 in females.
E. c. scaber is a scorpion from the northern Aegean area, with a dark coloration, an higher number of pectinal teeth, an higher trichobothrial pattern, and in addition, a body totally covered by granules of various size, as also the name suggests, whereas Euscorpius rahsenae sp. n. is light yellowish-brown, without a particularly accentuated granulation. E. c. ossae is an oligotrichous form, dark brown in colour with lighter legs and telson. It was described from Mount Ossa, in Thessaly. This form can be distinguished mainly by the dark colour, the Pv=7 and et=5, compared with Pv=8 and Pe-et=6 of E. rahsenae sp. n. E. c. aegaeus is a light colored form described from the island of Antiparos, in the central-southern part of the Aegean Sea. Probably it is endemic in few islands in the central-south Aegean Sea. In addition, it is described as uniformly light yellow colored and females with pectinal teeth count 8 (Di Caporiacco 1950), while E. rahsenae sp. n. has carapace and pedipalps little darker, legs, telson and chelicerae lighter with carinae dark, distinctly brownish-blackish and pectinal teeth count 7 in females.

Ecology
Some specimens of Euscorpius rahsenae sp. n. were collected from city center (Beşevler and Çiftehavuzlar) and in a ruined building in Yalıçiftlik Village (Mudanya District) of Bursa Province. It shows that Euscorpius rahsenae sp. n. penetrates to human settlements and is an anthropotelerant species.
A large part of Mudanya is an urban area, but the Tirilye locality (Mudanya) has vegetation composed of red pine (Pinus brutia Ten.), torch pine (Pinus nigra Arn. subsp. pallasiana (Lamb)), olive trees (Olea europea L.), and maquis vegetation (Quercus sp., Erica arborea L., Juniperus oxycedrus L., Phillyrea latifolia L., Pistacia lentiscus L., Cistus spp., as main shrubs). The specimens were collected in this locality during night trips with UV light when sitting in cracks of the earthen wall along the roadsides in the forest.