Ephippiochthonius riberai, Zaragoza, Juan A., 2017

Zaragoza, Juan A., 2017, Revision of the Ephippiochthonius complex in the Iberian Peninsula, Balearic Islands and Macaronesia, with proposed changes to the status of the Chthonius subgenera (Pseudoscorpiones, Chthoniidae), Zootaxa 4246 (1), pp. 1-221 : 108-110

Ephippiochthonius riberai n. sp. ( Figs 179–183 )

Type locality. Spain, Valencian Community, Alicante province, Marina Alta comarca , Teulada, Moraira , Cova dels Rats Penats (38°41′12″N, 00°09′10″E; 51 m a.s.l.).

Distribution. Spain: Valencian Community.

Etymology. The species name honours Dr Carles Ribera (University of Barcelona), one of the collectors of the holotype, for his great contribution to the knowledge of the Araneae , particularly from the Iberian Peninsula and Canary Islands.

Diagnosis (♀). A medium-sized, hypogean Ephippiochthonius species of the tetrachelatus -group. Chelicera shorter than carapace, movable cheliceral finger without isolated subapical tooth (di) and spinneret strongly prominent in female, unknown for male, lyrifissure ldb present; no eyes or eye-spots, without preocular microsetae, posterior margin of carapace with 2 macrosetae; chelal hand weakly depressed at level of ib / isb, with long hump distad of ib / isb and moderate slope between trichobothria ib / isb and eb; fixed chelal finger with 20 teeth; movable chelal finger with 17 teeth, without marginal lamina; pedipalpal femur (♀) 6.0 times longer than broad, length 0.67 mm; chela (♀) 4.9 times longer than deep, length 0.90 mm; ratio movable chelal finger/chelal hand (♀) 1.4; all chelal lyrifissure patterns present with their standard complements.

Type material examined. ♀ holotype ( DEUA). Spain, Valencian Community, Alicante province, Marina Alta comarca , Teulada, Moraira , Cova dels Rats Penats (38°41′12″N, 00°09′10″E; 51 m a.s.l.), 01.V.1978, M. Blas, C. Ribera & J.A. Zaragoza.

Description (♀; ♂ unknown). Medium-sized, hypogean species, troglomorphic. Integument depigmented; hispid granulation on lateral surfaces of carapace, on cheliceral hand and on bases of chelal fingers.

Carapace ( Fig. 180 ) distinctly longer than broad and posteriorly constricted; medial part of anterior margin weakly prominent, without a well-defined epistome, and strongly dentate ( Fig. 179 ); without eyes or eye-spots. Chaetotaxy: 18 macrosetae and without preocular microsetae, formula 4:6:4:2:2, anteromedial setae 0.10 mm long, sublateral ocular setae 0.08 mm long; 4 lyrifissures anteriorly and 2 posteriorly.

Chelicera ( Figs 181, 182 ) shorter than carapace, with 6 setae and 1 lateral microseta on hand, seta vb short (length 0.05 mm); hand with 5 dorsal and 1 ventral lyrifissure, lyrifissure ldb present. Fixed finger with 11 teeth decreasing in size proximally, two distal teeth distinctly larger than others. Movable finger without an isolated subapical tooth (di), with 10 teeth decreasing in size proximally, the distal tooth larger than others; spinneret prominent in female, square angle shape ( Fig. 182 ), unknown for male; seta gl 0.52 from base of movable finger. Rallum with 11 blades. Serrula exterior with 14 blades, serrula interior 12 blades.

Chaetotaxy of tergites 4:4:4:4:6:6:6:6:1T2T1:4:1T2T1:0; tergites IX and XI each with 2 sublateral tactile setae. Chaetotaxy of sternites 10:(3)10(3):(2)7(2):8:6:6:6:6:2T1T2:0:2, sternite X with 2 submedial tactile setae.

Pedipalpal coxa with 5 setae (including 2 on manducatory process), distal marginal seta of disk 0.10 mm long; coxa I 3 + 3 marginal microsetae, distal marginal seta 0.06 mm long; II 4 + 9–11 bipinnate coxal spines, III 5 + 6 bipinnate coxal spines and IV 6; intercoxal tubercle bisetose.

Pedipalp with femoral chaetotaxy 3:6:3:5:1. Chela ( Fig. 183 ) with hand weakly depressed at level of ib / isb, with long hump distad of ib / isb and moderate slope between trichobothria ib / isb and eb; dorsal-antiaxial surface of the chelal hand between the hump and trichobothria eb / esb flattened, limited by a marked edge; ventral intercondylar bow-like protuberance (ip) present; chaetotaxy 4:5:3, seta ph3 lacking, setae ih1, ih3 and ih4 approximately level with trichobothria ib / isb; distal end of hand and bases of chelal fingers with sclerotized condylar complex. Fixed finger with 20 teeth, most pointed and all with dental canals, of these the 7 proximal teeth progressively decreasing in size, the distalmost one tiny and the subdistal small, dental row reaching up to halfway between trichobothria sb and b, 5 proximal microtubercles; tip of finger with an accessory tooth (td) on antiaxial face; one pair of short antiaxial sensory setae (as) at the finger base, 0.030–0.035 mm long, distance between them 0.043 mm, finger depth 0.050 mm at the base; 4 teeth at level of est / it occupying 0.1 mm, distance between successive apices 0.025–0.028 mm. Movable finger with 17 teeth, most with dental canals, the distal one tiny, the subdistal one small, up to halfway between trichobothria st and sb are pointed and well developed, decreasing in size proximally and becoming rounded, all with dental canals except the most proximal tooth, dental row reaching up to halfway between trichobothria sb and b, being slightly shorter than the fixed finger dental row, 2 microtubercles at base; basal apodeme long and apically indented; coupled sensilla pc slightly distad of trichobothrium sb. Trichobothria as in Fig. 183 ; trichobothrium ist distinctly distad of esb and well proximad of lyrifissure fb; distance between ib / isb and esb 1.1 times longer than between ib / isb and the base of the hand; distance between st and sb 2.2 times longer than that between sb and b. All chelal lyrifissure patterns present with their standard complements.

Measurements and ratios. Female holotype: Body 1.64. Carapace 0.47/0.42 (1.1). Chelicera 0.42/0.19 (2.1), movable finger 0.21. Pedipalp: femur 0.67/0.11 (6.0), patella 0.28/0.13 (2.1), chela 0.90/0.19 (4.9), hand 0.38 (2.1), movable finger 0.52; ratio movable finger/hand 1.4, femur/movable finger 1.3, femur/carapace 1.4, chela/carapace 1.9, chela/femur 1.4.

Remarks. Within the species of the tetrachelatus -group, E. riberai n. sp. shares with E. aini n. sp. and E. nudipes the following combination of characteristics: anophthalmic, without preocular microsetae, only 2 setae in posterior row of carapace and without isolated subapical tooth on movable cheliceral finger. E. riberai n. sp. is much stouter and smaller than E. nudipes and has a pedipalpal femur chaetotaxy of 3:6:3:5:1, as opposed to 3:6:2:6: 1 in the latter. Comparisons between E. riberai n. sp. and E. aini n. sp. are made in the key and in the remarks under the latter species.

Figures

FIGURES 179 – 183. Ephippiochthonius riberai n. sp., female holotype. 179, anterior margin of carapace, partial view; 180, carapace; 181, left chelicera; 182, fingers of left chelicera, partial view; 183, left chela, antiaxial view.