Antillobisium tomasi, Díaz & Zaragoza & Iborra, 2018

Díaz, René Barba, Zaragoza, Juan A. & Iborra, Germán López, 2018, A new Antillobisium species (Arachnida: Pseudoscorpiones: Bochicidae) from Cuba, with biogeographical and ecological remarks on the genus, Zootaxa 4461 (3), pp. 399-410 : 401-407

Antillobisium tomasi n. sp.

( Figs 3‒21 )

Type material. Male holotype: Cuba, Cueva del Pirata, Cayo Caguanes, Yagüajay , Sancti Spiritus, 22.38777 N, - 79.12472 W, 20 m asl, 16.IV.2016, collected by T.M. Rodríguez ( CZACC 3.3363 ) . Paratypes: 1 male (CZACC 3.3366), 2 females ( CZACC 3.3364 , CZACC 3.3365 ), same data as holotype, except 26.II.2006 , collected by P. de la Torre. 1 tritonymph ( CZACC 3.3367 ), Cueva Grande, Cayo Caguanes, Yagüajay , Sancti Spiritus, 22.39417 N, - 79.12444 W, 20 m asl, 18.VIII.1997 , collected by A. Reyes, in the dark part of the cave on the wall.

Diagnosis (Ƌ, ♀). The largest and most strongly troglomorphic species of the genus. Pedipalpal femur without a pronounced tubercle at base of antiaxial face and slightly shorter than patella. Chelal fingers with dentition undulating in distal half through cyclic changes in the orientation of the teeth. Pedipalp strongly granulated, femur (♂) length 4.17‒5.07 mm, (♀) 3.90‒4.18 mm, (♂) 11.0‒11.3 times longer than broad, (♀) 10.0‒10.5; chela+ (♂) length 5.68‒6.24 mm, (♀) 5.12‒5.42 mm, (♂) 9.8‒10.3 times longer than broad, (♀) 7.7‒8.1.

Etymology. The species is named after the Cuban biospeleologist and arachnologist Tomás Michel Rodríguez, who collected the holotype.

Description (Ƌ, ♀). A large bochicid, body length about 6 mm, with extremely troglomorphic facies ( Fig. 3 ). Integument depigmented; preserved specimens with opisthosoma and legs pale; carapace, chelicerae and pedipalps reddish.

Carapace. Elongate, maximum width at the anteromedial portion ( Fig. 4 ). Without eyes or eyes spots. Epistome lacking. Chaetotaxy 4‒6:6:5:2‒3:5‒6 (22‒26). One pair of anterior, medial and posterior lyrifissures. Numerous small pores over entire surface. Medial surface reticulated ( Fig. 5 ).

Coxal area. Manducatory process long and acute, with 2 distal setae on each side, disk of the pedipalpal coxa with 10‒16 setae, pedal coxa I: 7‒11 setae, II 5‒8, III 7‒8, IV 7‒10. Anterolateral process of coxa I rounded and moderately prominent; without medial process.

Opisthosoma. Elongate, pleural membranes smooth and longitudinally striate. Chaetotaxy of tergites: 4:4:4:4‒ 5:6:6:6:6:6:4‒5:4:2, tergite X with 4 and XI with 3‒4 tactile setae. Male sternite II with 31‒32 setae (11 medial and 21‒22 marginal and small), sternite III with 16‒20 small setae on posterior genital opening and 7‒9 marginal setae. Female sternite II with 10‒11 (2 medial and 8‒9 marginal), sternite III with 20‒23 setae, including marginal and scattered medial setae. Chaetotaxy of sternites IV‒XII 6‒8:7‒9:8‒10:8‒10:8‒10:5‒8:4‒7:2‒4:2; sternites VI‒VIII bear 2 small discal setae in addition to the marginal setae; sternite XI with all setae tactile. Stigmata on sternites III and IV with 2 setae.

Chelicera. Six setae on hand and one on movable finger, 0.74‒0.77 from base ( Fig. 6 ). Galea simple, length 0.11‒0.14 mm. Fixed finger with 10‒13 teeth, distal tooth larger than others, which are distinctly worn in holotype and some paratypes ( Fig. 7 ); movable finger with a very large distal tooth, turned slightly laterally to lodge the fixed finger, and 7‒8 teeth extending to middle of finger, worn in holotype and some paratypes ( Fig. 7 ). Rallum ( Figs 8 , 21 ) with four blades, distal blade smooth and distinctly shorter than others, which are anteriorly serrate in distal third and all approximately of the same length [one female paratype with the smooth blade in subdistal position, behind a serrate blade ( Fig. 21 )]. Serrula exterior with 33‒36 blades, serrula interior with 27 blades.

Pedipalps. All articles heavily granulated, less so on chelal hand. Trochanter short. Femur and patella very slender, femur ( Fig. 9 ) without glandular tubercle at base of antiaxial face, slightly shorter than patella ( Fig. 10 ) but distinctly longer than chelal fingers. Hand widest at middle; in dorsal view, with fusiform shape ( Fig. 11 ), in lateral view, ventral margin almost flat, dorsal margin weakly curved ( Fig. 12 ); 0‒3 chemosensory setae on dorsum of hand, thin and small, distinctly separated and distributed from ib to base of fixed finger ( Fig. 12 ). Trichobothria as in Figs 11‒12 ; trichobothrium ib located in basal half of dorsum of hand, eb in distal portion of hand; esb and isb at base of finger, medial portion of finger without trichobothria, ist distad of est and both isolated, it slightly distad of et, both trichobothria at tip of finger. Both chelal fingers with venedens and venom apparatus, nodus ramosus distad of trichobothrium ist in fixed and distad of st in movable finger. Fixed finger distinctly longer than movable finger. Fixed finger of male with 124‒131 (113‒115 in female) contiguous and pointed teeth down to base of fixed finger; distalmost teeth only slightly smaller than others ( Fig. 15 ); distal half of finger with dental row undulating with repeated changes in the orientation of the teeth in cycles of 2‒6 teeth ( Figs 16‒19 ); teeth in basal half pointed, straight ( Fig. 14 ); one strongly sclerotized protuberance with a tiny seta on paraxial face ( Figs 13 , 15 ), level with 12‒14th teeth, approximately at crossing point of fingertips. Movable finger with trichobothrium sb equidistant between b and st, trichobothrium st between levels of est and it when fingers closed; male with 101‒116 teeth (112‒113 in female), those in distal half with same shape and orientation as those of fixed finger, but deviations less marked; basal half of row straight, with rounded teeth and reaching back to level of trichobothrium isb.

Legs. Femur and patella distinctly granulated, other articles almost smooth; tarsi not swollen basally; subterminal setae apically feathery; claws smooth, arolia slightly longer than claws ( Fig. 20 ). Leg I: joint between basitarsus and telotarsus apparently immovable. Leg IV: femur/patella suture strongly oblique, femur less than ¼ length of femoropatella (F/F+P: 0.20); one tactile seta on tibia 0.30‒0.35 from base, basitarsus 0.33‒0.34, absent on telotarsus.

Measurements (in mm) followed by ratios in parentheses. Male holotype, followed by male paratype in square brackets (when different): Body 5.62 [6.04]. Carapace 2.04/1.34 (1.5) [2.00/1.28 (1.6)]. Chelicera 1.00/0.47 (2.1) [0.88/0.40 (2.2)], movable finger 0.62 [0.56]. Pedipalp: trochanter 1.30/0.60 (2.2) [1.10/0.52 (2.1)], femur 5.07/ 0.46 (11.0) [4.17/0.37 (11.3)], patella 5.30/0.46 (11.5) [4.36/0.40 (10.9)], patella pedicel 0.68 [0.58], chela+ 6.24/ 0.64 (9.8) [5.68/0.55 (10.3)], chela - 5.86 (9.2) [5.38 (9.8)], hand+ 2.56 (4.0) [2.20], hand - 2.24 (3.5) [1.90], hand pedicel 0.38 [0.30], movable finger 3.80 [3.32], fixed finger 3.98 [3.47]; ratio movable finger/hand+ 1.5, femur/ movable finger 1.3, femur/carapace 2.5 [2.1], chela+/carapace 3.1 [2.8], chela+/femur 1.2 [1.4]. Leg I: trochanter 0.66/0.37 (1.8) [0.55/0.32 (1.7)], femur 2.06/0.27 (7.6) [1.76/0.23 (7.7)], patella 0.82/0.24 (3.4) [0.68/0.20], tibia 2.14/0.15 (14.0) [1.81/0.14 (12.9)], basitarsus 0.45/0.13 (3.5) [0.40/0.11 (3.6)], telotarsus 1.59/0.11 (14.5) [1.43/ 0.09 (15.9)]; ratio femur/patella 2.5 [2.6], telotarsus/basitarsus 3.5 [3.6]. Leg IV: trochanter 0.94/0.37 (2.6) [0.78/ 0.30], femur+patella 3.41/0.44 (7.8) [2.95/0.38], femur 0.67/0.38 (1.8) [0.58 (1.5)], patella 2.98/0.44 (6.8) [2.60/ 0.38], tibia 2.94/0.19 (15.5) [2.56 (13.5)], basitarsus 0.43/0.16 (2.7) [0.40 (2.5)], telotarsus 2.30/0.13 (17.7) [2.10/ 0.11 (19.1)]; ratio telotarsus/basitarsus 5.3. Female paratypes: Body 5.63‒5.74. Carapace 1.80‒1.90/1.22‒1.26 (1.5). Chelicera 0.88‒0.91/0.43 (2.0‒2.1), movable finger 0.56‒0.57. Pedipalp: trochanter 1.05‒1.14/0.52‒0.56 (2.0), femur 3.90‒4.18/0.39‒0.40 (10.0‒10.5), patella 4.07‒4.22/0.39‒0.42 (10.0‒10.4), patella pedicel 0.55‒0.57, chela+ 5.12‒5.42/0.63‒0.70 (7.7‒8.1), chela - 4.82‒5.12 (7.3‒7.7), hand+ 1.99‒2.15 (3.1‒3.2), hand - 1.77‒1.85 (2.6‒ 2.8), hand pedicel 0.30, movable finger 3.11‒3.32, fixed finger 3.25‒3.50; ratio movable finger/hand+ 1.5‒1.6, femur/movable finger 1.3, femur/carapace 2.2, chela+/carapace 2.8‒2.9, chela+/femur 1.3. Leg I: trochanter 0.55‒ 0.57/0.33‒0.34 (1.7), femur 1.64‒1.70/0.22‒0.24 (7.1‒7.5), patella 0.67‒0.72/0.20‒0.21 (3.4), tibia 1.67‒1.74/ 0.13‒0.14 (12.4‒12.8), basitarsus 0.35‒0.37/0.11‒0.12 (3.1‒3.2), telotarsus 1.26‒1.38/0.09‒0.11 (13.1‒14.0); ratio femur/patella 2.4, telotarsus/basitarsus 3.6‒3.7. Leg IV: trochanter 0.75‒0.82/0.29‒0.32 (2.6), femur+patella 2.72‒ 2.91/0.32‒0.35 (8.3‒8.5), femur 0.54‒0.58/0.31‒0.33 (1.7‒1.8), patella 2.48/0.32‒0.35 (7.1‒7.8), tibia 2.23‒2.29/ 0.17‒0.18 (12.7‒13.1), basitarsus 0.37‒0.39/0.15‒0.17 (2.3‒2.6), telotarsus 1.92‒1.95/0.11‒0.12 (16.0‒17.7); ratio telotarsus/basitarsus 5.0‒5.1.

Tritonymph. Carapace damaged. Apex of pedipalp coxa with 2 setae, rest of coxa with 5 setae. Coxa I‒IV each with 5 setae. Chaetotaxy of tergites 4:4:4:4:5:6:6:5:6:4:4:2. Chaetotaxy of sternites III‒XII 8:8:7:8:6:8:6:?:4:2; sternites VI‒VIII with 2 small discal setae in addition to marginal setae; sternite XI with all setae tactile. Stigmata on sternites III and IV with 1 seta. Cheliceral palm with 5 setae, subgaleal seta on movable finger 0.38 from base; galea long and simple, length 0.46 mm; fixed finger with 11 teeth, distal tooth larger than others; movable finger with 7 teeth, distal tooth very large and sublateral; rallum with 4 blades, with the same form as in adults; serrula exterior with 31 blades, serrula interior with 22 blades. Pedipalp: fixed chelal finger with trichobothrium ist distad of est; trichobothria isb and sb lacking; fixed finger with 108 teeth; movable finger with 109 teeth. Legs much as in adult, a distinct suture between basitarsi and telotarsi, telotarsi not swollen, leg IV F/ F+P 0.15.

Measurements (in mm): Body 3.62. Carapace 1.49/1.01 (1.5). Chelicera 0.75/0.35 (2.1), movable finger 0.46. Pedipalp: trochanter 0.74/0.42 (1.8), femur 2.82/0.31 (9.0), patella 2.90/0.34 (8.5), patella pedicel 0.47, chela+ 3.79/ 0.59 (6.4), chela - 3.59/0.59 (6.1), hand+ 1.56 (2.6), hand - 1.36 (2.3), hand pedicel 0.20, movable finger 2.40, fixed finger 2.42; ratio movable finger/hand+ 1.5, femur/movable finger 1.2, femur/carapace 1.9, chela+/carapace 2.5, chela+/femur 1.3. Leg I: trochanter 0.44/0.25 (1.8), femur 1.27/0.20 (6.4), patella 0.55/0.17 (3.2), tibia 1.19/0.12 (9.9), basitarsus 0.30/0.11 (2.7), telotarsus 1.00/0.12 (8.5); ratio femur/patella 2.3, telotarsus/basitarsus 3.3. Leg IV: trochanter damaged, femur+patella 2.12/0.29 (7.3), femur 0.31/0.29 (1.1), patella 1.86/0.29 (6.4), tibia 1.70/0.15 (11.3), basitarsus 0.34/0.14 (2.4), telotarsus 1.55/0.10 (15.5); ratio telotarsus/basitarsus 4.5.

Remarks. A. tomasi n. sp. is easily distinguishable from the other two Antillobisium species by its considerably larger size and extreme slenderness of the appendages. In addition, it differs from A. vachoni Dumitresco & Orghidan, 1977 by the absence of a tubercle at the base of the antiaxial face of the pedipalpal femur.

Figures

FIGURE 3. Antillobisium tomasi n. sp., male habitus.

FIGURES 4–8. Antillobisium tomasi n. sp., male holotype. 4, carapace; 5, reticular surface magnified; 6, right chelicera; 7, distal parts of right cheliceral fingers; 8, left cheliceral rallum.

FIGURES 9–13. Antillobisium tomasi n. sp., male holotype, right pedipalp. 9, trochanter and femur, dorsal view; 10, patella, dorsal view; 11, chela, near-dorsal view; 12, chela, antiaxial view; 13, tips of chelal fingers, paraxial view. Abbreviation: se, sensillum.

FIGURES 14–21. Antillobisium tomasi n. sp., female paratype, SEM images. 14, dental row in basal half of fixed finger (finger accidentally cracked longitudinally), ventral view; 15, dental row in apical part of fixed finger, arrow points to sensillum (se) partially hidden by debris, ventral view; 16, dental row, portion of distal half, with inset at higher magnification, dorsal view; 17–19, dental row, portion of distal half, at successively higher magnifications, ventro-antiaxial view; 20, apex of leg IV, with inset of distal end of subterminal seta at higher magnification, antiaxial view; 21, right cheliceral rallum. Abbreviation: se, sensillum.