Thaiderces tuoyuan Li & Chang sp. nov. Figs 1D, 2F, 16, 17, 28B, 29

Types.

Holotype: ♂ (IZCAS), Thailand, Yala Province, Than To District, outside Krasaeng Cave, 02°11.9998'N, 101°11.5512'E, 86 m, 25.X.2015, Yao Z. Paratype: 1♀ (IZCAS), same data as holotype.

Etymology.

The species name is a noun in apposition derived from the Chinese pinyin tuŏyuán (oval) and refers to the ovoid shape of the bulb.

Diagnosis.

Thaiderces tuoyuan sp. nov. is similar to T. jian, but males can be distinguished by the obovate bulb (vs. oblong bulb in T. jian), the position of the entire bulb is a mirror image of that of T. jian but theembolus arises from the opposite position in the two species; females can be distinguished by having one pair of spermathecae (vs. two pairs in T. jian).

Description.

Male (holotype). Total length 1.40; carapace 0.54 long, 0.55 wide; abdomen 0.86 long, 0.54 wide. Carapace round and brown, with three longitudinal dark brown bands of nearly equal width (Fig. 16C). Chelicerae brown (Fig. 28B). Clypeus dark brown medially and light brown laterally. Endites pale yellow. Labium dark brown. Sternum dark brown, with median pale yellow band delimitating the two halves of the sternum. Abdomen elongated, dorsum with light brown stripes posteriorly (Fig. 16C), anteroventrally with a brown semi-circle, posterior part with pair of pale yellow vertical dotted lines laterally and a V-shaped mark medially. Legs uniformly brown; measurements: I‒III missing, IV 5.38 (1.38, 0.20, 1.60, 1.40, 0.80). Palp (Fig. 17 A–D): femur four times longer than patella; patella not swollen, tibia 2/3 the length of femur; cymbium scattered with concentrated purplish spots, half the length of femur; bulb light yellow, obovate with embolus arising distally; embolus short and curved, 1/3 the length of the bulb (Fig. 17C, D).

Female (Paratype). General features and coloration similar to that of male (Fig. 16D, E). Measurements: total length 1.62; carapace 0.50 long, 0.62 wide; abdomen 1.12 long, 0.70 wide. Leg measurements: I 4.30 (1.09, 0.20, 1.30, 1.09, 0.62), II missing, III 3.46 (0.80, 0.16, 0.94, 0.93, 0.63), IV 5.47 (1.25, 0.16, 1.56, 1.41, 1.09). Endogyne: a pair of twisted spermathecae, opposing one another, blunt distal parts 3 times wider than the width of stalks, stalk 2 times longer than the head (Fig. 16A).

Distribution.

Known only from the type locality (Fig. 29).