Tetrablemma kepense, Lin, Yucheng, Li, Shuqiang & Jaeger, Peter, 2018

Lin, Yucheng, Li, Shuqiang & Jaeger, Peter, 2018, Tetrablemmidae, a spider family newly recorded from Cambodia (Arachnida, Araneae), ZooKeys 777, pp. 43-55 : 43-44

Tetrablemma kepense sp. n. Figs 1, 2, 6

Type material.

Holotype ♂ (SMF), CAMBODIA: Kep Province, Kep, Phnom Kep, secondary forest, leaf litter, elevation 105 m, 10°28'50"N, 104°17'50"E, 4-8 July 2017, P. Jäger leg., sieving. Paratypes 7♂, 8♀ (5 ♂, 6♀ SMF; 2♂, 2♀ NHMSU), same data as holotype.

Etymology.

The specific name refers to the type locality; adjective.

Diagnosis.

With the exception of T. marawula Lehtinen, 1981, T. brevidens Tong & Li, 2008, T. thamin Labarque & Grismado, 2009, and T. ziyaoense Lin & Li, 2014, this new species can be distinguished from other congeners by the lack of modified teeth or tubercle on the clypeus or the ocular area in both sexes, the embolus furcated at proximally 1/3 position, the extra-long inner vulval plate nearly 3 × as long as the central process (Figs 1 E–H, 2 B–C, F–G). It differs from T. marawula by the wider bulb, the sharpened embolic tip and the longer straight inner vulval plate (Figure 2A, B, D, G vs. Lehtinen 1981: figs 266, 283); differs from T. brevidens by the more strongly coiled spermophor, the furcate embolus, the thinner long inner vulval plate, and shorter postgenital scutum (Figure 2A, C, G vs. Tong 2013: figure 97 E–H); male differs from T. thamin by the narrower palpal tibia, the larger bulb, and the bifurcate embolic tip (trifurcate in T. thamin ), female by the presence of a central process and the longer inner vulval plate (Figure 2A, C, D, G vs. Labarque and Grismado 2009: figs 1-3); and differs from T. ziyaoense by the converging cheliceral horns, the reticulated clypeus in both sexes (smooth in female of T. ziyaoense ), the course and outlet position of spermophor, the precurved posterior margin of the pulmonary scutum, the thinner, straight inner vulval plate, the narrower vulval stem, and the lack of a distinct furrow on the preanal scutum (Figs 1 A–H, 2 A–G vs. Lin and Li 2014: figs 13 A–H, 14 A–D, 15 A–C).

Description.

Male (holotype). Measurements: total length 1.08; carapace 0.42 long, 0.37 wide, 0.34 high; abdomen 0.70 long, 0.58 wide, 0.35 high; clypeus 0.14 high; sternum 0.28 long, 0.29 wide. Length of legs: I 1.29 (0.43, 0.12, 0.32, 0.20, 0.22); II 1.22 (0.40, 0.11, 0.30, 0.20, 0.21); III 1.08 (0.33, 0.11, 0.25, 0.19, 0.20); IV 1.38 (0.45, 0.12, 0.36, 0.23, 0.22).

Prosoma (Figure 1A, B, E, G): reddish-brown, carapace finely reticulated, marginally rugose; four eyes in one group, in posterior half of carapace, white with black ocular base, ALE>PLE, ALE and PLE adjacent; cephalic part raised; clypeus high, sloping forward, with sparse setae, marginally round; cheliceral horns long, distal tip sharp, and tilted, cheliceral lamina developed; endites basally wide, distally narrow, labium triangular, distally blunt; sternum irregularly reticulated, scutellate, marginally strongly rugose, posterior corner truncated. Legs: yellowish-orange, cuticle striated; tibiae I–III with three trichobothria, four on tibia IV, and one on metatarsi I–IV. Opisthosoma: pale reddish-brown, dorsal scutum oval, surface nearly smooth, slightly granulated, posteriorly truncated; ventral scutum reticulated; lateral scutum I long, and exceeding beyond the posterior margin of preanal scutum; postgenital scutum straight; preanal scutum approximately oblong, slightly curved.

Palp (Figure 2 A–D): femoral cuticle granulated, approx. 2.5 x longer than patella; patella normal; tibia large, swollen, approx. 1.5 x wider than femur, with a trichobothrium disto-dorsally; cymbium short, triangular from lateral view, bearing long setae; bulb pear-shaped, surface smooth; embolus tubular, distinctly sclerotized, arising from the apex of bulb; embolic tip sharply pointed, lamellar bifurcation at proximally 1/3 position; spermophor coiled into two loops, abruptly twisting to narrow, and open at the embolic tip.

Female (one paratype). Measurements: total length 1.16; carapace 0.44 long, 0.38 wide, 0.34 high; abdomen 0.72 long, 0.61 wide, 0.37 high; clypeus 0.13 high; sternum 0.28 long, 0.30 wide. Length of legs: I 1.26 (0.42, 0.12, 0.31, 0.20, 0.21); II 1.19 (0.40, 0.11, 0.29, 0.19, 0.20); III 1.09 (0.34, 0.11, 0.26, 0.18, 0.20); IV 1.34 (0.44, 0.12, 0.35, 0.22, 0.21).

Prosoma (Figure 1C, D, F, H): coloration and modification as in male, but ocular area in anterior part of the carapace, chelicerae without long horn, only a small nodule fronto-proximally. Clypeus slightly lower than in male, palps distinctly reduced, palpal tibia with a dorsal trichobothrium. Legs as in male. Opisthosoma: dorsal and ventral scuta as in male, except for darker coloration; lateral scutum I long, extending beyond posterior margin of preanal scutum; postgenital scutum long, bearing a row of long setae, mesally narrow, laterally wide; preanal scutum more smooth, wider than long, nearly rectangular, with sparse stiff setae.

Epigyne and vulva (Figure 2F, G): epigynal fold long and obvious; epigynal pit distinct, gap-shaped, opening at the posterior margin of the pulmonary scutum; vulval stem sclerotized; vulval ducts weakly sclerotized, translucent, widely “V” -shaped, apical end connected to seminal receptacles; seminal receptacles inflated, saccular, transparent; inner vulval plate extra-long, straightly tubular, broad at base; central process short, proximally contracted, distally swollen.

Habitat.

Forest leaf litter.

Distribution.

Known only from the type locality (Figure 6).