Plistobunus Pocock, 1903

Zhang, Chao & Martens, Jochen, 2020, A taxonomic study on Epedanidae from Thailand including functional aspects of male genital morphology (Opiliones, Laniatores), ZooKeys 915, pp. 25-58 : 25

Plistobunus Pocock, 1903

Plistobunus Pocock 1903: 447; Roewer 1912: 232; 1923: 207; 1938: 124; Lian et al. 2011: 41.

Type species.

Plistobunus rapax Pocock, 1903, by original designation.

Extended diagnosis.

Medium-sized epedanines (2.40-3.57 mm) with a long median spine on the ocularium. Prosoma with a row of 4-6 setiferous tubercles on each side of the frontal margin. Areae II and IV with or without long spines. The basichelicerite of chelicerae elongate and armed with numerous tubercles, dorsally with three in males and with two in female ( Lian et al. 2011: 42, figs 2, 3; 44: 9, 10; 46: 18, 19. Figs 33-35 , 47-49 ). Pedipalpal femur of male ventrally with 9-13 seta-tipped tubercles, and distally with one or two tubercles on medial side. Pedipalpal patella with at least three seta-tipped tubercles. Distitarsus of leg I with two segments. The distal part of pars basalis of penis widened and with a stereoscopic ventral plate. Stylus columnar. Capsula interna ventrally and capsula externa dorsally surround the stylus.

Included species.

Plistobunus rapax Pocock, 1903, Plistobunus columnarius Lian et al., 2011, and Plistobunus jaegeri sp. nov.

Distribution.

China (Hong Kong and Hainan Island), Thailand (Ubon Ratchathani).

Sexual dimorphism.

The species of this genus possess conspicuous sexual dimorphism in the armature of the appendages. The tubercles or spines in male on the basichelicerite of chelicerae, and those of the femur of pedipalps and legs are much more robust or conspicuous than those of in female; the shape of body is very similar in both sexes.

The numbers of seta-tipped tubercles distally on medial side of pedipalpal femur gives an impression of the differences between the species. Male specimens of P. rapax and P. columnarius are described with two ( Lian et al. 2011: 42, fig. 6; 44, fig. 14) and those of P. jaegeri sp. nov. with only one such tubercle (Fig. 38 ). Females of P. columnarius ( Lian et al. 2011: 46, fig. 22) and P. jaegeri sp. nov. (Fig. 52 ) possess no tubercles of this size or position (female of P. rapax unknown).

Figures

Figures 32 - 39. Plistobunus jaegeri sp. nov., male holotype 32 body, lateral view 33 left chelicera, medial view 34 same, lateral view 35 left basichelicerite, dorsal view 36 left cheliceral hand, frontal view 37 left cheliceral fingers, frontal view 38 left pedipalp, medial view 39 same, lateral view. Scale bars: 1 mm (32 - 36, 38, 39), 0.5 mm (37).

Figures 40 - 54. Plistobunus jaegeri sp. nov. male (Figs 40 - 44, holotype) and female (Figs 45 - 54, paratype) 40, 45 body, dorsal view 41 right leg I, retrolateral view 42 - 44, 46 femur of right legs, retrolateral view 42 leg II 43 leg III 44 leg IV 46 leg I 47 left chelicera, medial view 48 same, lateral view 49 left basichelicerite, dorsal view 50 left cheliceral hand, frontal view 51 left cheliceral fingers, frontal view 52 left pedipalp, medial view 53 ovipositor, ventral view 54 same, dorsal view. Scale bars: 1 mm (40 - 46, 52), 0.5 mm (47 - 51), 0.25 mm (53, 54).