Spelaeochthonius yinae sp. nov.

urn:lsid:zoobank.org:act: 022ECCAC-A3CD-4BD4-876D-3167FD2CF413

Figs 3, 5A–B

Diagnosis

Differs from the other members of the genus Spelaeochthonius by the following combination of characters: carapace without eyes or eyespots, anterior margin with 6 setae, posterior margin with 2 setae (male 15 setae, female 16 setae); epistome present, composed of 6 teeth, heavily sclerotised; cheliceral hand with 5 lyrifissures, fixed cheliceral finger with large subapical tooth, rallum with 11 blades; and male coxae I with 7 coxal blades, female with 8 coxal blades, each terminally trifurcate blades; fixed chelal finger with 23 acute teeth, movable chelal finger with 14 teeth. Tergite I–II each with 2 setae. Pedipalpal femur (♂) 7.65 ×, (♀) 7.26 × as long as broad, length (♂) 1.30 mm, (♀) 1.38 mm; chela (♂) 5.93 ×, (♀) 6.30 × as long as broad, length (♂) 1.72 mm, (♀) 1.89 mm; ratio movable chelal finger/chelal hand (♂) 1.36 ×, (♀) 1.40 ×.

Etymology

The specific epithet was given in honour of Mrs Hao-Min Yin due to the assistance provided during fieldwork.

Type material

Holotype CHINA • ♂; Yunnan Province, Zhaotong City, Doushaguan Town, Xiao Cave; 28°02.405′ N, 104°06.845′ E; 708 m a.s.l.; 11 Apr. 2017; Yun-Chun Li leg.; MCWNU (Ar-Ps-YN-0081).

Paratype CHINA • 1 ♀; same collection data as for holotype; MCWNU (Ar-Ps-YN-0008) .

Description

Adult male

COLOURS. Chelicerae, pedipalps, and legs reddish brown, remaining parts yellow brown.

CARAPACE (Fig. 3A–B). Subquadrate, 0.90 × as long as broad, without furrows; lateral margins constricted posteriorly, eyes absent but eye region bulging and convex in dorsal view; epistome present, composed of 6 teeth, heavily sclerotised. With 15 setae arranged 6: 2: 3: 2: 2.

CHELICERA. Relatively broad. Cuticle of hand gently granulate to squamate. Hand with 6 setae and 5 lyrifissures, all setae acuminate, movable finger with 1 seta in medial position, galea present as a very low mound. Fixed finger with 1 medium-sized distal tooth and 11 progressively smaller proximal teeth; movable finger with 12 teeth (Fig. 3C). Serrula exterior with 22 lamellae; serrula interior with 18 lamellae. Rallum composed of 11 blades with fine barbules, basal-most 1 distinctly shorter than others (Fig. 3E).

PEDIPALP (Fig. 3H–J). All setae acuminate. Hand of chela narrowed at base of fingers. Trochanter 1.56 ×, femur 7.65 ×, patella 2.33 × as long as broad, femur 3.10 × as long as patella. Chela 5.93 ×, hand 2.48 × as long as broad; movable chelal finger 1.36 × as long as hand. Fixed finger with 23 acute teeth, with middle ones larger than that in both ends; movable finger with 14 teeth. Fixed chelal finger with 8 trichobothria and movable finger with 4, eb, esb, ib, isb, and ist located basally of the fixed finger, it and est distomedial and forming a pair, it slightly more distal than est; et subdistal and duplex xs distal; on movable finger, st subproximal and in medial position on finger, triplet sb, b, and t distomedial to distal, distance between sb and b almost equal to distance between b and t.

ABDOMEN. Tergal chaetotaxy (I–XII): 2: 2: 4: 4: 4: 6: 7: 7: 6: 6: 4: 0; sternal chaetotaxy (IV–XII): 13: 11: 10: 11: 10: 12: 10: 0: 2. Manducatory process with 2 setae. Pedipalpal coxa with 3 setae, coxa I 6, II 6, III 5, IV 4–5 setae; intercoxal tubercle present with 2 setae. Coxae I with 7 coxal blades, each terminally trifurcate blades (Fig. 3D). Anterior genital operculum with 9 setae, without lyrifissures; genital opening with 8 setae on the right side and 7 on the left (Fig. 3L).

LEGS (Fig. 3F–G). Leg I: trochanter 1.34 × as long as deep, femur 7.40 × as long as deep and 2.00 × as long as patella, patella 4.11 × as long as deep, tibia 4.57 × as long as deep, tarsus 13.00 × as long as deep. Leg IV: trochanter 1.56 × as long as deep, femur+ patella 4.62 × as long as deep, femur shorter than patella, tibia 6.55 × as long as deep, metatarsus 3.78 × as long as deep, tarsus 15.00 × as long as deep. Metatarsus with 1 tactile seta (sub-basal, TS = 0.20), tarsus with 1 tactile seta (sub-basal, TS = 0.18). Subterminal tarsal setae not distally serrate, arolium slightly shorter than claws and not divided; all claws simple.

Adult female

Mostly the same as the holotype.

CARAPACE. 0.97 × as long as broad. With a total of 16 setae, including 6 on the anterior margin and 4 on the posterior margin.

PEDIPALP. Trochanter 1.58 × as long as broad, femur 7.26 × as long as broad, patella 2.47 × as long as broad, femur 2.94 × as long as patella. Chela 6.30 × as long as broad, hand 2.5 × as long as broad; movable finger 1.40 × as long as hand.

ABDOMEN. Tergal chaetotaxy (I–XII): 2: 2: 4: 4: 4: 5: 6: 7: 5: 5: 2: 0; sternal chaetotaxy (IV–XII): 11: 11: 10: 10: 11: 11: 7: 0: 2. Coxae I with 8 coxal blades, each terminally trifurcate blades. Genital opening slit-like, anterior genital operculum with 6 setae, with 2 lyrifissures (Fig. 3M).

DIMENSIONS (length/width or, in the case of the legs, length/depth in mm). Male (female in parentheses): body length 2.64 (3.06). Carapace 0.53/0.59 (0.61/0.63). Pedipalp: trochanter 0.28/0.18 (0.30/0.19), femur 1.30/0.17 (1.38/0.19), patella 0.42/0.18 (0.47/0.19), hand 0.72/0.29 (0.75/0.30), length of movable chelal finger 0.98 (1.05), chela 1.72/0.29 (1.89/0.30). Leg I: trochanter 0.22/0.16 (0.24/0.18), femur 0.74/0.10 (0.80/0.11), patella 0.37/0.09 (0.42/0.10), tibia 0.32/0.07 (0.35/0.08), tarsus 0.78/0.06 (0.82/0.07). Leg IV: trochanter 0.25/0.16 (0.32/0.17), femur+patella 0.97/0.21 (1.04/0.22), tibia 0.72/0.11 (0.78/0.12), metatarsus 0.34/0.09 (0.38/0.08), tarsus 0.90/0.06 (0.95/0.08).

Distribution

China (Yunnan).

Habitat

The cave was about 5–20 m high, 15–80 m wide, and its length was unknown. The new species were collected from under damp, shaded gravel about 80 m from the cave entrance. At the same time, some species of spiders, millipedes and neobisiid pseudoscorpions were also collected.