Chthonius aeneae, 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 : 10

Chthonius (E.) aeneae n. sp.

( Figs 1–8 , 293 )

Type locality: Italy, Liguria, Genoa Prov., Sestri Levante, Punta Manara (44°15ʹ17ʺN 9°24ʹ21ʺE).

Distribution. Italy: Liguria.

Diagnosis (3Ƥ). An anophthalmic endogean Chthonius (Ephippiochthonius) that differs from other species of the C. fuscimanus group in the following combination of characters: movable cheliceral finger with isolated subapical tooth (di) and with spinneret weakly raised in males; preocular microsetae absent; pedipalpal hand (in lateral view) without a rounded hump distad of trichobothria ib-isb, weakly depressed at level of ib-isb; fixed chelal finger with 10–11 triangular teeth, at level of est-it with 5 teeth occupying 0.1 mm (distance between successive apices 0.020–0.021 mm); proximal half of movable chelal finger with thick and weakly undulated marginal lamina; length of chela 0.49–0.51 (3), 0.55–0.565 (Ƥ) mm, length of movable chelal finger 0.29–0.30 (3), 0.32–0.325 (Ƥ) mm; chela 5.6–5.7 (3), 5.0–5.1 (Ƥ) times as long as deep; ratio of pedipalpal femur/carapace 1.2 (3Ƥ).

Type material. ITALY — Liguria: Genoa Prov.— 1 3 (holotype), 4 3, 2 Ƥ (paratypes), Sestri Levante, Punta Manara (44°15ʹ17ʺN 9°24ʹ21ʺE), 140 m a.s.l., 23.II.1993, G. Gardini leg., sieved under Quercus ilex (holotype deposited in MHNG, paratypes in G. Gardini coll., Genoa).

Derivatio nominis. The species is named in memory of the late Enea Gardini, my father.

Description of adults (Ƥ). Integument with weak pigmentation, carapace, tergites, chelicerae and pedipalps pale yellow-brown; hispid granulation—more marked in males—on lateral surface of carapace, on cheliceral palm and on the base of pedipalpal femur. Carapace 1.0 times longer than broad, subquadrate, posteriorly slightly constricted; anterior margin (figs 1–2) strongly dentate between median macrosetae, with small epistome in males; ocular area as in fig. 3, no eyes or eye-spots; chaetotaxy 4:6:4:2:2(18), macrosetae thick, preocular microsetae absent; length of anteromedian macrosetae 0.07–0.08 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; sternite III rarely with (3)7(3) setae; genital opening of males flanked by 6 (rarely 5) setae on each side. Chelicerae (figs 4–5) 2.0–2.2 times as long as broad, palm with 6 setae and 2 microsetae laterally; fixed finger with 6–7 teeth proximally reduced in size and 8–10 proximal microtubercles; movable finger with a large subapical tooth (di), at the same level with the spinneret in females, 4– 5 contiguous teeth and 3–4 proximal microtubercles; gl ratio 0.55–0.61; spinneret weakly raised in males, prominent and apically rounded in females; 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 6–7 coxal spines, coxa III with 3–4 coxal spines; intercoxal tubercle bisetose. Pedipalp (figs 6–8): femur 5.6–5.65 (3), 4.75–4.9 (Ƥ) times as long as broad; chela 5.6–5.7 (3), 5.0–5.1 (Ƥ) times as long as deep; hand of chela 2.3–2.35 (3), 2.1–2.2 (Ƥ) times as long as deep, depressed at level of ib-isb, with a weak and deep hump distad of ib-isb; fixed chelal finger with 11–12 triangular teeth with dental canals: the first proximal tooth mostly with rounded tip and the three distal teeth gradually reduced in size distally; base of fixed finger with 4–12 microtubercles; tip of fixed finger with a modified accessory tooth (td) on antiaxial face; pedipalpal fixed finger at level of est-it with 5 teeth occupying 0.1 mm (distance between successive apices 0.020–0.021 mm); distal half of movable finger with 7 triangular, upright teeth, the distal one smaller, with dental canals; proximal half of movable finger with thick and weakly undulated marginal lamina; coupled sensilla pc just proximad of sb; trichobothria as in figs 7–8, eb-esb-ist placed in a straight line or with ist a little distad of the line eb-esb; basal apodeme of movable finger strongly sclerotized, narrowed apically; ratio of movable finger/hand of chela 1.4–1.45 (3), 1.35–1.4 (Ƥ); ratio of pedipalpal femur/movable finger 1.2 (3Ƥ); ratio of pedipalpal femur/carapace 1.2 (3Ƥ).

Measurements (in mm). Body length 0.91–0.98 (3), 1.0–1.05 (Ƥ). Carapace 0.29–0.30 × 0.27–0.29 (0.23–0.26 anteriorly) (3), 0.31–0.315 × 0.31–0.32 (0.265–0.29 anteriorly) (Ƥ). Chelicerae 0.22–0.23 × 0.10–0.11 (3), 0.255– 0.26 × 0.13 (Ƥ), movable finger length 0.105–0.12 (3), 0.13 (Ƥ). Pedipalp: femur 0.34–0.365 × 0.06–0.065 (3), 0.38–0.39 × 0.08 (Ƥ); chela 0.49–0.51 × 0.085–0.09 (3), 0.55–0.565 × 0.11 (Ƥ); hand length 0.20–0.21 (3), 0.23– 0.24 (Ƥ); movable finger length 0.29–0.30 (3), 0.32–0.325 (Ƥ).

Remarks. Among the species of the Chthonius fuscimanus group, C. aeneae n. sp. is closely related to C. nanus and C. tyrrhenicus , both epigean common and widespread in the same geographical area, and to C. intemelius , from western Liguria. It differs from the first two species in the absence of eyes, of preocular microsetae and in the form of the spinneret, which is weakly raised in males; it differs from C. nanus in its smaller size [length of chela 0.49–0.51 mm (3), 0.55–0.565 mm (Ƥ) in C. aeneae , versus 0.52–0.65 mm (3), 0.56–0.73 mm (Ƥ) in C. nanus ]. It can be separated from C. tyrrhenicus by the shape of pedipalpal hand (with gentle slope between trichobothria ib-isb and eb-esb-ist in C. aeneae , with abrupt slope in C. tyrrhenicus ) and in having the pedipalps more slender [chela 5.6–5.7 (3), 5.0–5.1 (Ƥ) times as long as deep in C. aeneae , versus 4.6–5.4 (3), 4.1– 4.7 (Ƥ) in C. tyrrhenicus ]. C. aeneae differs from C. intemelius in the absence of eyes (reduced but still present in C. intemelius ) and the absence of preocular microsetae (two preocular microsetae on each side in C. intemelius ), and in having the pedipalps more slender [chela 5.2–5.4 (3), 4.6–4.75 (Ƥ) times as long as deep in C. intemelius ]. C. aeneae n. sp. has been collected by digging in deep soil in Quercus ilex wood on sandstone.

Figures

FIGURES 1 – 6. Chthonius (E.) aeneae n. sp. 1, male holotype, anterior margin of carapace; 2, female paratype, id.; 3, male holotype, anterolateral portion of carapace; 4, male holotype, right chelicera; 5, female paratype, id.; 6, male holotype, tip of fixed chelal finger, dorsal view.

FIGURES 7 – 8. Chthonius (E.) aeneae n. sp. 7, male holotype, right chela, lateral view; 8, female paratype, id. (Scale bar 0.1

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.