Chthonius latellai, 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 : 63-66

Chthonius (E.) latellai n. sp.

( Figs 121–128 , 292 )

Type locality: Italy, Latium, Latina Prov., Bassiano, Grotta di Fiume Coperto 1361 La/LT (41°31ʹ0 6.8ʺN 12°59ʹ38.1ʺE).

Distribution. Italy: Latium.

Diagnosis (Ƥ). 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) at level with the spinneret; carapace without epistome and with 2 preocular microsetae on each side; pedipalpal hand (in lateral view) without a rounded hump distad of trichobothria ib-isb; fixed and movable chelal finger respectively with 13–14 and 8–9 triangular teeth; fixed chelal finger at level of est-it with 3 teeth occupying 0.1 mm (distance between successive apices 0.035–0.040 mm); proximal half of pedipalpal movable finger with straight, thick marginal lamina, weakly undulated; length of chela 1.14–1.19 (3), 1.27 (Ƥ) mm, length of movable chelal finger 0.66–0.70 (3), 0.74 (Ƥ) mm; chela 8.2–8.4 (3), 7.9 (Ƥ) times as long as deep; ratio of pedipalpal femur/carapace 1.8–1.9 (3Ƥ).

Type material. ITALY— Latium: Latina Prov. — 1 3 (holotype) 1 Ƥ (paratype), Bassiano, Monti Lepini, Grotta di Fiume Coperto 1361 La/LT (= Gr. dell’Acquapuzza) (41°31ʹ0 6.8ʺN 12°59ʹ38.1ʺE), 21 m a.s.l., 6.XI.1997, L. Latella leg., sulphurous cave; 1 3 (paratype, with broken opisthosoma), Bassiano, Monti Lepini, Grotta della Cava 384 La/LT, 27 m a.s.l., 13.VIII.1997, L. Latella leg. (holotype deposited in MHNG, paratypes in G. Gardini coll., Genoa).

Derivatio nominis. The species is dedicated to Leonardo Latella (Museo Civico di Storia Naturale, Verona) as an appreciation of his contributions to our knowledge of the subterranean fauna of central and southern Italy.

Description of adults (Ƥ). Highly specialized troglomorphic facies; integument without pigmentation; hispid granulation on lateral surface of carapace, on cheliceral palm and on pedipalpal hand. Carapace 1.0 times longer than broad, posteriorly constricted; anterior margin (figs 121–122) closely dentate between median macrosetae, without epistome; ocular area as in fig. 123, no eyes or eye-spots; chaetotaxy mm 4mm:6:4:2:2 (18), macrosetae slightly thick; length of anteromedian macrosetae 0.13–0.14 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 6–8 setae on each side. Chelicerae (figs 124–125) 2.3–2.4 times as long as broad, palm with 6 setae and 2 microsetae laterally; fixed finger with 9–10 teeth (worn in female paratype) proximally reduced in size and 3–6 proximal microtubercles; movable finger with a large isolated subapical tooth (di) level with spinneret and 9–10 teeth (worn in female paratype), the first 2 distal teeth joined together and prominent; movable finger with 5 proximal microtubercles; gl ratio 0.56–0.59; spinneret weakly prominent and apically rounded in male, prominent and apically sharpened in female; 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 (rarely 6), IV 6; coxa II with 12 coxal spines, coxa III with 5 coxal spines; intercoxal tubercle bisetose. Pedipalp: femur 8.2–8.3 (3Ƥ) times as long as broad; chela (figs 126–128) 8.2–8.4 (3), 7.9 (Ƥ) times as long as deep; hand of chela 3.2–3.4 (3) 3.3 (Ƥ) times as long as deep, weakly depressed proximad of trichobothria ib-isb and with a weak hump distad of ib-isb; fixed chelal finger with 13–14 triangular, upright teeth and one proximal tooth with tip rounded, all with dental canals; base of fixed finger with 3–4 microtubercles; tip of fixed finger with a modified accessory tooth (td) on antiaxial face; fixed chelal finger at level of est-it with 3 teeth occupying 0.1 mm (distance between successive apices 0.035–0.040 mm); distal half of movable chelal finger with 8–9 triangular, upright teeth with dental canals and one proximal vestigial tooth without dental canal; proximal half of movable chelal finger with thick, straight marginal lamina, irregularly undulated in female; coupled sensilla pc nearer sb than b; trichobothria as in figs 127–128, ist distad of the line eb-esb; basal apodeme of movable finger strongly sclerotized, long and fine; ratio of movable finger/hand of chela 1.4–1.5 (3Ƥ); ratio of pedipalpal femur/movable finger 1.2– 1.25 (3Ƥ); ratio of pedipalpal femur/carapace 1.8–1.9 (3Ƥ).

Measurements (in mm). Body length 1.7 (3), 1.95 (Ƥ). Carapace 0.46 × 0.44–0.45 (0.42–0.43 anteriorly) (3), 0.51 × 0.49 (0.46 anteriorly) (Ƥ). Chelicerae 0.42–0.44 × 0.175–0.19 (3), 0.48 × 0.20 (Ƥ), movable finger length 0.21–0.23 (3), 0.24 (Ƥ). Pedipalp: femur 0.83–0.86 × 0.10–0.105 (3), 0.92 × 0.11 (Ƥ); chela 1.14–1.19 × 0.135– 0.145 (3), 1.27 × 0.16 (Ƥ); hand length 0.46–0.47 (3), 0.53 (Ƥ); movable finger length 0.66–0.70 (3), 0 74 (Ƥ).

Remarks. Among the species of the Chthonius fuscimanus group, C. latellai n. sp. is probably related to the epigean C. tyrrhenicus , occurring in the same geographical area, from which it differs in most troglomorphic characters.

C. latellai n. sp. differs from other hypogean species of central Italy ( C. magrinii , C. etruscus and C. sulphureus ) in a higher degree of troglomorphy. It differs from C. magrinii , also from Latium, in the presence of two preocular microsetae on each side (no microsetae in C. magrinii ), in the absence of an epistome (weakly prominent in C. magrinii ), in its greater size and more elongated appendages [length of chela 1.14–1.19 (3) mm, chela 8.2–8.4 (3) times as long as deep, ratio of pedipalpal femur/carapace 1.8–1.9 in C. latellai ; length of chela 0.85–0.88 (3) mm, chela 6.8 (3) times as long as deep, ratio of pedipalpal femur/carapace 1.5 in C. magrinii ] and in the dentition of the chelal fingers (fixed chelal finger at level of est-it with 3 teeth occupying 0.1 mm, distance between successive apices 0.035–0.040 in C. latellai ; fixed chelal finger at level of est-it with 4 teeth occupying 0.1 mm, distance between successive apices 0.030 in C. magrinii ). Comparisons between C. latellai and C. etruscus are made in the Remarks under the latter species. C. latellai differs from C. sulphureus , from Marche, in the position of di with respect to the spinneret (level with spinneret in C. latellai , proximad of spinneret in C. sulphureus ) and in the more elongated appendages [chela 8.2–8.4 (3) 7.9 (Ƥ) times as long as deep, ratio of pedipalpal femur/carapace 1.8–1.9 in C. latellai ; chela 7.2–7.4 (3) 6.6–6.9 (Ƥ) times as long as deep, ratio of pedipalpal femur/carapace 1.7–1.8 in C. sulphureus ].

Like C. sulphureus , C. latellai , inhabits a karstic complex characterized by the presence of hydrogen sulphide (Latella et al. 1999).

Figures

FIGURES 121 – 126. Chthonius (E.) latellai n. sp. 121, male holotype, anterior margin of carapace; 122, female paratype, id.; 123, male holotype, anterolateral portion of carapace; 124, id., right chelicera; 125, female paratype, fingers of right chelicera; 126, male holotype, tip of fixed chelal finger, dorsal view.

FIGURES 127 – 128. Chthonius (E.) latellai n. sp. 127, male holotype, right chela, lateral view; 128, female paratype, id. (Scale bar 0.1 mm).

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.