Chthonius

Gardini, Giulio, 2013, A revision of the species of the pseudoscorpion subgenus Chthonius (Ephippiochthonius) (Arachnida, Pseudoscorpiones, Chthoniidae) from Italy and neighbouring areas, Zootaxa 3655 (1), pp. 1-151 : 33-35

[ Chthonius (E.) corsicus Callaini, 1981 ]

( Figs 50–53 )

Chthonius corsicus Callaini 1981: 315 , figs IIIa–f, IV.

Type locality: France, Corsica, Dept. Haute-Corse, Bastia, San-Martino-di-Lota (42°43ʹ26ʺN 9°27ʹ21ʺE).

Distribution. Corsica.

Diagnosis (3). An oculated epigean Chthonius (Ephippiochthonius) from Corsica that differs from other species of the C. fuscimanus group in the following combination of characters: movable cheliceral finger without isolated subapical tooth (di); fixed chelal finger at level of est-it with 4 teeth occupying 0.1 mm (distance between successive apices 0.026 mm); length of chela 0.655–0.67 (3), length of pedipalpal movable finger 0.38–0.39 (3); ratio of pedipalpal femur/carapace 1.35–1.4 (3).

Material examined. FRANCE — Corsica: 1 3, Bastia, near Erbalunga, 22.V.1982, S. Zoia & A. Torchia leg., Quercus ilex wood on limestone.

Description of adult (3; Ƥ unknown). Integument with weak pigmentation, carapace, tergites, chelicerae and pedipalps pale brown; evident hispid granulation on lateral surface of carapace, on cheliceral palm and on base of movable chelal finger. Carapace 1.05–1.1 times as long as broad, subquadrate, posteriorly weakly constricted; anterior margin (fig. 50) between median macrosetae with spaced out denticles, without epistome; ocular area as in fig. 51, anterior eyes with fairly convex lens (diameter 0.028 mm), posterior eyes reduced to a smooth cuticular area; distance from anterior eyes to anterior margin of carapace 0.03 mm; chaetotaxy mm 4mm:6:4:2:2 (18), macrosetae fine; length of anteromedian macrosetae 0.08 mm. Chaetotaxy of tergites I–X 4:4:4:4:6:6:6:6:6:4. Chaetotaxy of sternites II–X 10:(3)8(3):(2)7(2):7o8:6:6:6:6:7; genital opening of males flanked by 6–8 setae on each side. Chelicerae (figs 52) 2.1–2.4 times as long as broad, palm with 6 setae and 1 or 2 microsetae laterally; fixed finger with 6–7 subequal teeth and 5–6 proximal microtubercles; movable finger with 5 teeth proximally reduced in size and 3–4 proximal microtubercles, isolated subapical tooth (di) absent; gl ratio 0.59; spinneret weakly raised; rallum with 11 blades; serrulae interior and exterior respectively with 12 and 14 blades. Coxal setae: pedipalp 5 (including 2 on manducatory process), I 3 + 3 marginal microsetae, II 4, III 5, IV 6; coxa II with 7–9 coxal spines, coxa III with 4–5 coxal spines; intercoxal tubercle bisetose. Pedipalp (fig. 53): femur 5.6–6.0 times as long as broad, with hispid granulation basally; chela 5.5–5.8 times as long as deep; hand of chela 2.4–2.5 times as long as deep, weakly depressed at level of ib-isb, without hump distad of ib-isb; fixed chelal finger with 12–13 triangular teeth with dental canals, the two distal teeth smaller, the first proximal tooth smaller and with tip rounded; base of fixed finger with 6–7 microtubercles; tip of fixed finger with a modified accessory tooth (td) on antiaxial face; fixed chelal finger at level of est-it with 4 teeth occupying 0.1 mm (distance between successive apices 0.026 mm); distal half of movable chelal finger with 7 upright, triangular teeth, the proximal one smaller, with dental canals; proximal half of movable finger with thick marginal lamina weakly undulated, with vestiges of 3 teeth back to sb; coupled sensilla pc at level with sb; trichobothria as in fig. 53, ist a little distad of the line eb-esb; basal apodeme of movable finger strongly sclerotized, squat, apically truncate; ratio of movable finger/hand of chela 1.3–1.35; ratio of pedipalpal femur/movable finger 1.2–1.3; ratio of pedipalpal femur/carapace 1.35–1.4.

Measurements (in mm). Body length 1.20–1.26. Carapace 0.35 × 0.32–0.33 (0.29 anteriorly). Chelicerae 0.27– 0.28 × 0.11–0.137, movable finger length 0.14–0.15. Pedipalp: femur 0.47–0.48 × 0.08–0.084; chela 0.655–0.67 × 0.115–0.12; hand length 0.29; movable finger length 0.38–0.39.

Remarks. Among the species of the Chthonius fuscimanus group, C. corsicus is related to C. giustii and C. siscoensis , both from Corsica. It differs from the epigean C. giustii in its larger size [length of chela 0.655–0.67 mm (3) in C. corsicus , 0.33–0.36 mm (3) in C. giustii ], the shape of pedipalpal hand (weakly depressed at level of ibisb with a rectangular profile in C. corsicus , depressed at level of ib-isb with a square profile in C. giustii ) and the pedipalps being more slender [chela 5.5–5.8 (3) times as long as deep in C. corsicus , 4.8–5.15 (3) in C. giustii ]. C. corsicus differs from the hypogean C. siscoensis in many troglomorphic characters.

The above redescription of C. corsicus incorporates the original one of Callaini (1981).

Figures

FIGURES 50 – 53. Chthonius (E.) corsicus Callaini, 1981, male (Corsica, Bastia, near Erbalunga). 50, anterior margin of carapace; 51, anterolateral portion of carapace; 52, right chelicera; 53, right chela, lateral view.