Occidenchthonius setosus ( Mahnert, 1993 ) Mahnert, 1993

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 : 202-203

Occidenchthonius setosus ( Mahnert, 1993) , n. comb.

( Fig. 316 )

Chthonius (Ephippiochthonius) setosus Mahnert 1993: 979 –980, figs 17–20, table 1.

Type locality. Spain, Canary Islands, Santa Cruz de Tenerife province, Tenerife Island, Anaga massif, Tegueste , Pedro Álvarez (28°31′29″N, 16°18′51″W; 561 m a.s.l.) .

Distribution. Spain: Canary Islands.

Diagnosis (♀). An eyeless hypogean, medium-sized Occidenchthonius species of the machadoi -group. Movable cheliceral finger with isolated subapical tooth (di) and with small spinneret in female, unknown for male, lyrifissure ldb present; without eyes or eye-spots, anterior margin of carapace with 7–9 preocular microsetae on each side, posterior margin with 2 macrosetae; chelal hand weakly depressed at level of ib / isb, with short and flattened hump distad of ib / isb and gentle slope between trichobothria ib / isb and eb; chaetotaxy 4:4:4; fixed chelal finger with 22 teeth; distal half of movable chelal finger with 13 pointed teeth with dental canals, basal half of movable chelal finger with 13 rounded, partially fused, vestigial teeth, without canals, on raised lamina; pedipalpal femur (♀) 5.9 times longer than broad, length 0.77 mm; chela (♀) 6.2 times longer than deep, length 1.09 mm; ratio movable chelal finger/chelal hand (♀) 1.6; lacking lyrifissures ma1 and ma2, all other chelal lyrifissure patterns present with their standard complements.

Type material examined. ♀ holotype ( MHNG), Spain, Canary Islands, Santa Cruz de Tenerife province, Tenerife Island, Anaga massif, Tegueste , Pedro Álvarez (28°31′29″N, 16°18′51″W; 561 m a.s.l.), MSS, 03.VII.1988, leg. A.L. Medina .

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

Carapace slightly longer than broad and weakly constricted posteriorly; medial part of anterior margin weakly prominent, without a well-defined epistome, and strongly dentate; without eyes or eye-spots. Chaetotaxy: 16 setae, with 16 (7+9) preocular microsetae, 2 setae in posterior row, macrosetal formula 4:4:4:2:2, anteromedial setae 0.15 mm long, sublateral ocular setae identical to preocular microsetae, lateral ocular setae 0.11 mm; 4 lyrifissures anteriorly and 2 posteriorly.

Cheliceral hand with 6 setae and 4 lateral microsetae, seta vb short (0.030 mm long), microsetae 0.015–0.028 mm; hand with 5 dorsal and 1 ventral lyrifissure, lyrifissure ldb present. Fixed finger with 12 teeth decreasing in size proximally, two distal teeth distinctly larger than others. Movable finger with an isolated subapical tooth (di), with 10 teeth decreasing in size proximally and 1 proximal microtubercle, the distal tooth larger than others; spinneret small and apically rounded in female, unknown for male; seta gl 0.61 from base of movable finger. Rallum with 11 blades. Serrula exterior with 15 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, tactile seta XI 0.42 mm long. Chaetotaxy of sternites 10:(3)9(3):(2)7(2):8:6:6:6:6:2T1T2:0:2, lateral setae on sternite III macrosetal in size, sternite X with 2 submedial tactile setae.

Pedipalpal coxa with 5 setae (including 2 on manducatory process), distal marginal seta of disk 0.10 mm long; coxa I 3 + 3 marginal microsetae, distal marginal seta 0.09 mm long; II 4 + 6–9 bipinnate coxal spines, III 5 + 4 bipinnate coxal spines and IV 6; intercoxal tubercle bisetose.

Pedipalp with femoral chaetotaxy 3:6:3:5:1. Chela ( Fig. 316 ) with hand weakly depressed at level of ib / isb, with short and flattened hump distad of ib / isb and gentle slope between trichobothria ib / isb and eb; marked hollow before base of movable finger with thicker cuticle; width equal to depth; chaetotaxy 4:4:4, seta ph3 present, seta ih5 absent; distal end of hand and bases of chelal fingers with sclerotized condylar complex. Fixed finger with 22 mostly pointed teeth and with dental canals, 6 proximal teeth decreasing in size and the most proximal rounded, first two distal teeth small, third tooth of normal row (mt) of fixed finger distinctly modified in shape and deviated in orientation with respect to the others, dental row reaching up to halfway between trichobothria sb and b, about 20 proximal microtubercles; tip of finger with an accessory tooth (td) on antiaxial face; one pair of long antiaxial sensory setae (as) at the base, one level with and other markedly distad of lyrifissure fb, 0.045 mm long, distance between them 0.055 mm, fixed finger depth at the base 0.058 mm; 4 teeth at level of est / it occupying 0.1 mm, distance between successive apices 0.025–0.028 mm. Distal half of movable finger with 13 pointed teeth with dental canals that reach up to halfway between trichobothria st and sb, the distal tooth tiny and on a low protuberance, the subdistal one small; basal half of movable chelal finger with 13 rounded, partially fused, vestigial teeth, without canals, on raised lamina; dental row reaching halfway between trichobothria sb and b, 5 proximal microtubercles; basal apodeme long and apically indented; coupled sensilla pc halfway between trichobothria sb and b. Trichobothria as in Fig. 316 ; trichobothrium ist slightly proximad of esb and well proximad of lyrifissure fb; distance between ib / isb and esb approximately equal to that between ib / isb and the base of the hand; distance between st and sb 1.7 times longer than that between sb and b; lacking lyrifissures ma1 and ma2, all other chelal lyrifissure patterns present with their standard complements.

Measurements and ratios. Female holotype: Body 1.64. Carapace 0.55/0.52 (1.1). Chelicera 0.51/0.25 (2.1), movable finger 0.26. Pedipalp: femur 0.77/0.13 (5.9), patella 0.31/0.14 (2.2), chela 1.09/0.18 (6.2), hand 0.41 (2.4), movable finger 0.67; ratio movable finger/hand 1.6, femur/movable finger 1.1, femur/carapace 1.4, chela/carapace 2.0, chela/femur 1.4.

Remarks. Within the machadoi -group, O. setosus shares the absence of eyes with the Canarian species O. lopezi , O. oromii n. sp. and O. tenerifae , but it differs from them in bearing supernumerary preocular and ocular microsetae. The above description incorporates in part that of Mahnert (1993).

Figures

FIGURE 316. Occidenchthonius setosus (Mahnert, 1993) n. comb., female holotype, left chela, antiaxial view. FIGURE 317. Occidenchthonius tamaran (Mahnert, 2011) n. comb., male paratype, left chela, antiaxial view.