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 : 54-57

[ Chthonius (E.) giustii Callaini, 1981 ]

( Figs 98–105 )

Chthonius giustii Callaini 1981: 309 , figs Ia–g, IIa–b.

Type locality: France, Corsica, Dept. Haute-Corse, Corte, Forêt de Cervello (42°11ʹN 9°07ʹE). Distribution. Corsica.

Diagnosis (Ƥ). An eyed 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 with 10–12 triangular teeth, at level of est-it, with 5–6 teeth occupying 0.1 mm (distance between successive apices 0.019–0.021 mm); length of chela 0.47–0.54 (3), 0.53–0.61 (Ƥ) mm, length of pedipalpal movable finger 0.28–0.31 (3), 0.30–0.35 (Ƥ) mm; chela 4.8–5.15 (3), 4.1–4.3 (Ƥ) times as long as deep; ratio of pedipalpal femur/carapace 1.1–1.2 (3Ƥ).

Type material examined. FRANCE— Corsica— 2 3 1 Ƥ (paratypes), “ Corsica, Bois de Cervello, muschi e terriccio di Arbutus sp., 21.IV.1980 ” “G. Callaini det., paratypus ” (1 3 1 Ƥ MSNG, unusable permanent microscope slides, left chela of female deformed; 1 3 MSNV, depository not stated by Callaini 1981: 315).

Other material examined. FRANCE— Corsica –1 3, Castagniccia, near Cervione, 4.VI.1982, A. Torchia & S. Zoia leg., sieved in Quercus ilex wood; 1 3 1 Ƥ, Foresta di Vizzavona, 1000–1400 m a.s.l., 28.V.1982, A. Torchia & S. Zoia leg., Fagus sylvatica wood.

Description of adults (Ƥ). Integument pigmented, carapace, tergites, chelicerae and pedipalps brown; lateral surfaces of carapace, cheliceral palm, ventrodistal surface of pedipalpal hand and base of movable chelal finger with weakly cuticular hispid granulation. Carapace 1.0–1.1, subquadrate; anterior margin (figs 98–99) dentate between median macrosetae, weakly prominent; ocular area as in fig. 100, anterior eyes with weakly convex lens (diameter 0.028 mm), posterior eyes reduced to cuticular smooth area, both eyes with tapetum; distance from anterior eyes to anterior margin of carapace 0.030 mm; chaetotaxy mm(or m) 4mm (or m):6:4:2:2 (18), macrosetae fine; length of anteromedian macrosetae 0.06–0.08 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):8:6:6:6:6:7; genital opening of males flanked by 5–7 setae on each side. Chelicerae (figs 101–102) 2.0–2.1 times as long as broad, palm with 6 setae and 2 microsetae laterally; fixed finger with 6–9 teeth proximally reduced in size and 5–6 proximal tubercles; movable finger without isolated subapical tooth (di), with 5–7 teeth proximally reduced in size and 3–4 proximal tubercles; gl ratio 0.59–0.61; spinneret large and prominent, apically rounded, similar in both sexes; 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 4–8 (mostly 5–6) coxal spines, coxa III with 2–5 (mostly 3) coxal spines; intercoxal tubercle bisetose. Pedipalp: femur 5.0–5.4 (3), 4.6–5.15 (Ƥ) times as long as broad; chela (figs 103– 105) 4.8–5.15 (3), 4.1–4.3 (Ƥ) times as long as deep; hand of chela 2.1–2.25 (3), 1.9–2.0 (Ƥ) times as long as deep, depressed at level of ib-isb; fixed chelal finger with 10–12 teeth with dental canals: the first distal tooth smaller, the 1–2 proximal teeth apically rounded, the others upright, large, triangular and weakly reclined; base of fixed finger with 5–7 microtubercles; tip of fixed finger with a modified accessory tooth (td) on antiaxial face; pedipalpal fixed finger at level of est-it with 5–6 teeth occupying 0.1 mm (distance between successive apices 0.019–0.021 mm); distal half of movable finger with 5–7 upright, large, triangular teeth with dental canals and 1 very small distal tooth; proximal half of movable finger with thick marginal lamina, weakly undulated, sometimes with vestigial teeth; coupled sensilla pc level with sb; trichobothria as in figs 104–105, eb-esb-ist placed mostly in a straight line, or with ist at level of esb or proximad of esb; basal apodeme of movable finger strongly sclerotized, squad, apically truncated; ratio of movable finger/hand of chela 1.2–1.4 (3), 1.2–1.3 (Ƥ); ratio of pedipalpal femur/ movable finger 1.2 (3Ƥ); ratio of pedipalpal femur/carapace 1.1–1.2 (3Ƥ).

Measurements (in mm). Body length 1.0–1.1. Carapace 0.28–0.33 × 0.26–0.30 (0.24–0.26 anteriorly) (3), 0.32–0.35 × 0.315–0.35 (0.29–0.30 anteriorly) (Ƥ). Chelicerae 0.22–0.25 × 0.11–0.12 (3), 0.26–0.30 × 0.13–0.15 (Ƥ), movable finger length 0.12–0.13 (3), 0.14–0.16 (Ƥ). Pedipalp: femur 0.33–0.36 × 0.06–0.07 (3), 0.37–0.43 × 0.07–0.09 (Ƥ); chela 0.47–0.54 × 0.095–0.11 (3), 0.53–0.61 × 0.12–0.145 (Ƥ); hand length 0.21–0.23 (3), 0.25– 0.29 (Ƥ); movable finger length 0.28–0.31 (3), 0.30–0.35 (Ƥ).

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

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

Figures

FIGURES 98 – 103. Chthonius (E.) giustii Callaini, 1981 (Corsica, Forêt de Vizzavona). 98, male, anterior margin of carapace; 99, female, id.; 100, male, anterolateral portion of carapace; 101, male, right chelicera; 102, female, id.; 103, male, tip of fixed chelal finger, dorsal view.

FIGURES 104 – 105. Chthonius (E.) giustii Callaini, 1981 (Corsica, Forêt de Vizzavona). 74, male, right chela, lateral view; 75, female, id. (Scale bar 0.1 mm).