Ephippiochthonius ibiza Zaragoza, 2017, n. sp.
Creators: name: Zaragoza, Juan A.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Pseudoscorpiones
Chthoniidae
Ephippiochthonius
Ephippiochthonius ibiza

description: Ephippiochthonius ibiza n. sp. (Figs 154–158)
Type locality. Spain, Balearic Islands, Ibiza, Portinatx, Cova de sa Caperulla (39°06′14″N, 01°32′07″E; 111 m a.s.l.).
Distribution. Spain: Balearic Islands.
Etymology. The species name is a noun in apposition from the island on which the type locality is situated.
Diagnosis (♀). A large, microphthalmic, strongly troglomorphic Ephippiochthonius species of the tetrachelatus -group. Movable cheliceral finger without isolated subapical tooth (di) and spinneret prominent in female, unknown for male, lyrifissure ldb present; anterior eyes with weakly convex lens, posterior eyes absent; 1– 2 preocular microsetae on each side, posterior margin of carapace with 2 macrosetae; chelal hand weakly depressed at level of ib / isb, with distinct, short and weakly conical, hump distad of ib / isb and gentle slope between trichobothria ib / isb and eb; fixed chelal finger with 33–34 teeth; movable chelal finger with 32–33 teeth, without marginal lamina; pedipalpal femur (♀) 9.8–9.9 times longer than broad, length 1.57–1.58 mm; chela (♀) 6.2–6.6 times longer than deep, length 2.06–2.07 mm; ratio movable chelal finger/chelal hand (♀) 1.4; all chelal lyrifissure patterns present with their standard complements, lyrifissures fd and hd with increased number.
Type material examined. ♀ holotype, 1 ♀ paratype (both DEUA), Spain, Balearic Islands, Ibiza, Portinatx, Cova de sa Caperulla (39°06′14″N, 01°32′07″E; 111 m a.s.l.), 25.II.2007, leg. A. Sendra.
Description (♀; ♂ unknown). Large, hypogean species, strongly troglomorphic. Integument depigmented; hispid granulation on lateral surfaces of carapace, on cheliceral hand and weakly on bases of chelal fingers.
Carapace (Fig. 155) distinctly longer than broad and strongly constricted posteriorly; medial part of anterior margin distinctly prominent, without a well-defined epistome, and strongly dentate (Fig. 154); anterior eyes with small and weakly convex lens (diameter 0.025–0.030 mm) and far from anterior margin of carapace (0.065–0.070 mm), posterior eyes absent. Chaetotaxy: 18 macrosetae and 1‒2 preocular microsetae on each side, macrosetal formula 4:6:4:2:2, anteromedial setae 0.16–0.17 mm long, sublateral ocular setae 0.08 mm long, ocular medial setae even longer than the anteromedial; 4 lyrifissures anteriorly and 2 posteriorly.
Chelicera (Figs 156, 157) with 6 setae and 2 lateral microsetae on hand, seta vb short (length 0.075–0.090 mm); hand with 5 dorsal and 1 ventral lyrifissure, lyrifissure ldb present. Fixed and movable fingers with strongly worn teeth of unrecognizable number in bot holotype and paratype, two distal teeth distinctly larger than others in the fixed finger, one in the movable finger. Movable finger without an isolated subapical tooth (di); spinneret prominent, of medium size and rounded in female (Fig. 157), unknown for male; seta gl 0.58 from base of movable finger. Rallum with 11 blades. Serrula exterior with 17–18 blades, serrula interior 13 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 (0.31 and 0.41 mm long, respectively). Chaetotaxy of sternites 10–11:(3)10(3):(2)7(2):8:6:6:6:6:2T1T2:0:2, lateral setae on sternite III microsetal in size, sternite X with 2 submedial tactile setae.
Pedipalpal coxa with 5 setae (including 2 on manducatory process), distal marginal seta of disk 0.17–0.19 mm long; coxa I 3 + 3 marginal microsetae, distal marginal seta 0.11 mm long; II 4 + 9–13 bipinnate coxal spines, III 5 + 4–8 bipinnate coxal spines and IV 6; intercoxal tubercle bisetose.
Pedipalp with femoral chaetotaxy 3:6:2:7–8:1. Chela (Fig. 158) with hand weakly depressed at level of ib / isb, with distinct, short and weakly conical, hump distad of ib / isb and gentle 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 33–34 teeth, most pointed and all with dental canals, of these the 7–9 proximal teeth progressively decreasing in size, dental row reaching halfway between sensilla pc and trichobothrium b, 4–5 microtubercles at base; tip of finger with an accessory tooth (td) on antiaxial face; one pair of long antiaxial sensory setae (as) at the finger base, 0.060–0.075 mm long, distance between them 0.080–0.095 mm, finger depth 0.105 at the base; 4 teeth at level of est / it occupying 0.1 mm, distance between successive apices 0.025–0.030 mm. Movable finger with 32–33 teeth, most with dental canals, the distal one very tiny, up to halfway between trichobothria st and sb teeth are pointed and well developed, decreasing in size proximally and becoming rounded, becoming flattened at the proximal end, all with dental canals except 5 proximal teeth, dental row reaching up to proximad of sensilla pc being slightly shorter than the fixed finger dental row; basal apodeme long and apically indented; coupled sensilla pc halfway between sb and b, slightly closer to b. Trichobothria as in Fig. 158; trichobothrium ist slightly proximad of esb and well proximad of lyrifissure fb; distance between ib / isb and esb 1.0–1.1 times longer than that between ib / isb and the base of the hand; distance between st and sb 1.5–1.6 times longer than that between sb and b. All chelal lyrifissure patterns present, most with their standard complements, except female holotype with 4 lyrifissures fd on one chela and the normal number of 3 on the other chela and both females with duplicated lyrifissure hd.
Measurements and ratios. Female holotype, followed, when different, by female paratype in square brackets: Body 2.24 [2.14]. Carapace 0.82/0.66 (1.2) [0.76/0.65 (1.2)]. Chelicera 0.72/0.31 (2.3) [0.71/0.30 (2.4)], movable finger 0.38. Pedipalp: femur 1.57/0.16 (9.8) [1.58/0.16 (9.9)], patella 0.58/0.24 (2.4) [0.59/0.22 (2.6)], chela 2.07/ 0.32 (6.6) [2.06/0.33 (6.2)], hand 0.85 (2.7) [0.84 (2.5)], movable finger 1.15 [1.18]; ratio movable finger/hand 1.4, femur/movable finger 1.4 [1.3], femur/carapace 1.9 [2.1], chela/carapace 2.5 [2.7], chela/femur 1.3.
Remarks. Ephippiochthonius ibiza n. sp. is distinctly larger and more slender than the other microphthalmic species of the tetrachelatus -group, namely E. nerjaensis (Carabajal Márquez, García Carrillo & Rodríguez Fernández, 2001). They share the absence of an isolated subapical tooth (di) on the movable cheliceral finger and only 2 setae on the carapacal posterior margin, but E. ibiza n. sp. strongly differs from E. nerjaensis in the number of teeth on the movable chelal finger, having about 30 as opposed to about 7 in the latter. Additionally, the position of trichobothrium ist is proximad of esb in E. ibiza n. sp., whereas in E. nerjaensis it is distinctly distad.
description: Published as part of 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), pp. 1-221 in Zootaxa 4246 (1) on pages 87-89, DOI: 10.5281/zenodo.437611