Chthonius magrinii, Gardini, Giulio, 2013

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 : 72-74

Chthonius (E.) magrinii n. sp.

( Figs 146–150 , 292 )

Type locality: Italy, Latium, Frosinone Prov., San Giovanni Incarico, Grotta sulla strada per il Santuario della Madonna della Guardia n.c. La/FR (41°30ʹ24.4ʺN 13°33ʹ14.0ʺE).

Distribution. Italy: Latium.

Diagnosis (3). An anophthalmic hypogean Chthonius (Ephippiochthonius) from Latium that differs from other species of the C. fuscimanus group in the following combination of characters: movable cheliceral finger with isolated subapical tooth (di); carapace with weakly prominent epistome, without preocular microsetae; chelal hand (in lateral view) without a rounded hump distad of trichobothria ib-isb, weakly depressed at level of ib-isb; fixed and movable chelal fingers respectively with 13–14 and 8–9 triangular teeth; fixed finger at level of est-it with 4 teeth occupying 0.1 mm (distance between successive apices 0.030 mm); proximal half of pedipalpal movable finger with thick marginal undulated lamina; length of chela 0.85–0.88 mm, length of movable chelal finger 0.51– 0.53; chela 6.8 times as long as deep; ratio of pedipalpal femur/carapace 1.5.

Type material. ITALY— Latium: Frosinone Prov.— 1 3 (holotype) 1 3 (paratype, in poor condition), Northern Aurunci Mts, San Giovanni Incarico, Grotta sulla strada per il Santuario della Madonna della Guardia n.c. La/FR (13° 33ʹ 14.0ʺ E, 41° 30ʹ 24.4ʺ N), 201 m a.s.l., 5.X.2008, P. Magrini leg. (holotype deposited in MHNG, paratype in G. Gardini coll., Genoa).

Derivatio nominis. The species is dedicated to Paolo Magrini (Florence) in appreciation of his contributions to our knowledge of the Italian subterranean fauna.

Description (3, Ƥ unknown). Troglomorphic facies. Integument depigmented; marked hispid granulation on lateral surface of carapace, on cheliceral palm and on distal surface of chelal hand. Carapace 1.0–1.1 times longer than broad, posteriorly constricted; anterior margin (fig. 146) between median macrosetae with long and slender denticles forming a weak epistome; ocular area as in fig. 147, no eyes or eye-spots; chaetotaxy 4:6:4:2:2 (18), macrosetae little thick, no preocular microsetae; length of anteromedian macrosetae 0.10 mm. Chaetotaxy of tergites I–X 4:4:4:4:6:6:6:6:6:4. Chaetotaxy sternites II–X 10 or 11:(3)8(3):(2)7(2):8:6:6:6:6:7; genital opening of males flanked by 8–10 (6 in paratype) setae on each side. Chelicerae (fig. 148) 2.2–2.4 times as long as broad, palm with 6 setae and 1 or 2 microsetae laterally; fixed finger with 8–9 teeth proximally reduced in size and 4–5 proximal microtubercles; movable finger with an isolated subapical tooth (di), a little proximal with respect to the spinneret, 7–8 teeth proximally reduced in size and 4 proximal microtubercles; gl ratio 0.55–0.57; spinneret weakly raised, apically rounded; 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 (once 4) + 3 marginal microsetae, II 4, III 5 (once 6), IV 6; coxa II with 7–8 coxal spines, coxa III with 3–6 coxal spines; intercoxal tubercle bisetose. Pedipalp: femur 6.7–6.8 times as long as broad; chela (figs 149–150) 6.8 times as long as deep; hand of chela 2.6 times as long as deep, weakly depressed at level of ib-isb; fixed chelal finger with 14–15 teeth with dental canals, the first one or two teeth apically rounded, the others upright, triangular; base of fixed finger with 10–12 microtubercles; tip of fixed finger with a modified accessory tooth (td) on antiaxial face; pedipalpal fixed finger at level of est-it with 4 teeth occupying 0.1 mm (distance between successive apices 0.030 mm); distal half of movable chelal finger with 8–10 teeth: the distal one very small, sharp, 7 large, upright and triangular teeth with dental canals, and 1 or 2 vestigial proximal teeth; proximal half of movable chelal finger with thick marginal lamina, slender between sb and the finger base; coupled sensilla pc halfway between b-sb or nearer b than sb; trichobothria as in fig. 150, trichobothrium ist very distad of the line eb-esb; basal apodeme of movable finger strongly sclerotized, apically cut; ratio of movable finger/hand of chela 1.5; ratio of pedipalpal femur/movable finger 1.15–1.2; ratio of pedipalpal femur/carapace 1.5.

Measurements (in mm). Body length 1.4. Carapace 0.40 × 0.37–0.38 (0.34 anteriorly). Chelicerae 0.35–0.37 × 0.15–0.155, movable finger length 0.17–0.19. Pedipalp: femur 0.60–0.61 × 0.09; chela 0.85–0.88 × 0.125–0.13; hand length 0.33–0.345; movable finger 0.51–0.53.

Remarks. Among the species of the Chthonius fuscimanus group, C. magrinii n. sp. is probably related to the epigean C. tyrrhenicus of the same geographical area, from which it differs in most troglomorphic characters. It is also related to the hypogean C. latellai from Latium (see Remarks under latter).

Figures

FIGURES 146 – 150. Chthonius (E.) magrinii n. sp., male holotype. 146, anterior margin of carapace; 147, anterolateral portion of carapace; 148, right chelicera; 149, tip of fixed chelal finger, dorsal view; 150, right chela, lateral view.

FIGURES 290 – 293. Distribution maps for the Italian species of the Chthonius fuscimanus group. 290, Chthonius (E.) boldorii Beier, 1934; 291, Chthonius (E.) genuensis Gardini, 1990, C. (E.) gestroi Simon, 1896, C. (E.) monguzzii n. sp., C. (E.) pieltaini Beier, 1930, C. (E.) troglophilus Beier, 1930 and C. (E.) zoiai Gardini, 1990; 292, Chthonius (E.) etruscus n. sp., C. (E.) latellai n. sp., C. (E.) magrinii n. sp. and C. (E.) sulphureus n. sp.; 293, Chthonius (E.) aeneae n. sp., C. (E.) gallii n. sp., C. (E.) intemelius n. sp. and C. (E.) ligur n. sp.