Xinjiangsha stekolnikovi, Kalúz, Stanislav & Kováčik, Ján, 2012

Kalúz, Stanislav & Kováčik, Ján, 2012, Two new chiggers of the genus Xinjiangsha (Acari: Trombiculidae) and a key to species of the genus, Zootaxa 3595, pp. 77-88 : 83-84

Xinjiangsha stekolnikovi sp. nov.

Description of larva: SIF = 7BS-N-3-2 -1-1-1-1-0-0-0; fsp = 7-7-7; fPp = B.B.BBB; Ga = N; fCx = 1-1-1; fSt = 2- 2; DS = 78; VS = 40; NDV = 118; fDS = 4H-16-6-13-4- 10 -5-9-7-4 = 78.

Idiosoma ( Figs. 5 , 6 ). Scutum anteriorly and laterally subquadrate, posteriorly semi-rounded, slightly wider than long, with 2 AL, 1 AM, 2 PL, 2 PPL, 2 OS (scuto-ocular setae) and two sensilla. Small scutal puncta cover prevailing part of scutum. Sensilla flagelliform, 72 long, with 1–2 long cilia situated in second third of sensilla. Eyes oval, 2 + 2, in ocular plates, situated laterally at level of PL and OS. Humeral setae 49 long, anterior dorsal idiosomal setae 39 long and posterior dorsal idiosomal setae 49 long, thickly ciliated. Dorsal idiosomal setae arranged in irregular rows, varying in number and position of setae. Standard measurements: AW = 63, PW = 77, SB = 29, ASB = 26, PSB = 20, SD = 46, AP = 28, AM = 37, AL = 34, PL = 46, PPL = 46; PL=PPL=OS>AM>AL; SB>ASB>PSB; SD<AW<PW; SB situated anterior to level of PL and PPL. Ventral side of idiosoma with two pairs of sternal setae (fSt = 2-2), and 40 irregularly arranged thickly ciliated ventral setae, 27 of them situated anterior and/or laterally from excretory pore. Lengths of ventral setae increase from anterior (36) to median (40) and posterior (46) setae.

Gnathosoma ( Fig. 7 ). Galeala nude. Palps 75 long, 3-pronged palpotibial claw slender, 21 long, with deeply indented prongs. Chelicera of normal contour, cheliceral blade with usual tricuspid cup.

Legs ( Fig. 8 ). With pretarsus, claws and normal empodia. All setae on legs ciliated, slender. Specialized setae on leg segments—Leg I: tarsus I – S1, f1, (PT´, ST, pST) = N, 2 tibialae, microtibiala, 2 genualae, microgenuala; Leg II: tarsus II – S2, f2, PT´´= N, 2 tibialae, genuala; Leg III: tibiala, genuala, MTa. Number of ciliated setae on leg segments (leg formula) – Leg I: 1-1- 1-5-4-9-22; Leg II: 1-1-2-4-3-5-1; Leg III: 1-1- 2 -3-3-6-14.

Legs length: pa = 297, pm = 263, pp = 308, Ip = 868.

Differential diagnosis. Xinjiangsha stekolnikovi sp. nov. belongs to the group of Xinjiangsha species with two genualae I, two pairs of humeral setae (4H) and nude galeala, but differs from other similar species by the presence of 2 PPL and 2 OS. The related species Xinjiangsha feideri (Daniel and Brelih) differs from X. stekolnikovi by branched galeala, 3 genualae I and fD = 2H-8- 8. X. rychliki differs from X. stekolnikovi by having 4 PPL and 2 OS, 3 genualae I and fPp = B.B.NNB. The remaining Xinjiangsha species show other combination of features.

Etymology. The new species is named in honour of a well-known Russian acarologist Dr. Alexandr A. Stekolnikov.

Material studied. Holotype: 1 larva, Caucasus Mts., Elbrus Mt., Baksan valley, Tyrnyauz env., 43° 26' N, 42° 58' E, 10–16 August 1982 on adult female of Chionomys gud ; collected by J. Obuch. Holotype will be deposited in Slovak National Museum, Bratislava, Slovakia.

Remarks. The genus Xinjiangsha has a wide geographic distribution in the Palearctics from North-Western Africa and West Europe (Vercammen-Grandjean 1956; Brown 2008); through Turkey ( Stekolnikov & Daniel 2012) and Middle Asia ( Kudryashova 1998) to China ( Wen et al. 1984; Wen 2003). Few collections are published from Central Europe ( Kováčik & Kalúz 2010) and South and South-East Europe ( Daniel & Brelih 1959; Kolebinova 1970). The majority of Xinjiangsha species are known from the territories surrounding the Black Sea, e.g. Bulgaria ( Kolebinova 1992), Crimea ( Kudryashova 1998) and Caucasus Mts. ( Kudryashova 1998; Kováčik & Kalúz 2010).

The new described species X. rychliki sp. nov. and X. stekolnikovi sp. nov. come from Turkey and Caucasus, respectively. The finding of X. lyciaensis and X. rychliki from North-West Turkey ( Stekolnikov & Daniel 2012; this manuscript, respectively) enlarges the geographic distribution of Xinjiangsha and indicates that more representatives of this genus could occur south of the Black Sea.

Figures

FIGURE 5. Xinjiangsha stekolnikovi sp. nov. — idiosoma dorsal (scale = 100 µm). Legs length: pa = 244, pm = 228, pp = 266, Ip = 738.

FIGURE 6. Xinjiangsha stekolnikovi sp. nov. — idiosoma ventral (scale = 100 µm).

FIGURE 7. Xinjiangsha stekolnikovi sp. nov. –– gnathosoma (left— ventral aspect, right—dorsal aspect) (scale = 100 µm).

FIGURE 8. Xinjiangsha stekolnikovi sp. nov. — legs I – III (circles—bases of setae; solid circles—upper side; open circles—reverse side (scale = 100 µm).