Prothemenops Schwendinger, 1991

Schwendinger, Peter J. & Hongpadharakiree, Komson, 2014, Three new Prothemenops species (Araneae: Idiopidae) from central Thailand, Zootaxa 3893 (4), pp. 530-550 : 531-532

Prothemenops Schwendinger, 1991

Prothemenops Schwendinger, 1991: 233 . - World Spider Catalog 2014.

Type species. Prothemenops siamensis Schwendinger, 1991 by designation and by monotypy.

Emended diagnosis and description. Idiopid spiders (as defined by Raven 1985) distinguished from all other genera of the family by the unique presence of club-shaped trichobothria ( Fig. 1 C; rarely interspersed with clavate trichobothria) dorsally on all leg metatarsi but not on leg tarsi ( Fig. 1 A–B). Eye group only little wider than long, anteriorly narrower than posteriorly, occupying about one-third of carapace width at that point, with ALE situated at anterior margin of carapace, distinctly in front of remaining eyes ( Figs 2 A–B, E, 5A–B, D, 8A–B). Carapace hirsute, its cephalic region quite low, in males ( Figs 2 C, 8C) distinctly more so than in females ( Fig. 2 D). Fovea narrow (usually occupying not more than one-fifth of carapace width), median portion straight ( Fig. 2 L) or slightly procurved ( Fig. 8 D), always with recurved ends; posterior margin of fovea often with a more or less distinct indentation ( Figs 2 L, 8D). Rastellum sessile or on indistinct mound, in females stronger than in males. Palpal coxae with lunate prolateral zone being slightly sunken and of same colour ( Fig. 5 C) or more or less distinctly lighter than rest of article ( Fig. 8 E; in females more contrasting than in males); prolateral-proximal corner with thick cuspules in all females ( Figs 5 C, 8E); in males with unmodified bristles (often), with basally slightly incrassate bristles (often; Fig. 2 K), or with narrow cuspules or spicules (rarely). Labium usually without cuspules ( Figs 2 K, 5C, 8E), rarely with one cuspule (in few females). Sternum with short labio-sternal suture and with three pairs of small submarginal to marginal sigilla. No metatarsal preening combs. Scopulae always present on tarsi and metatarsi I–II, present or absent on tarsi III–IV and metatarsus III, always absent on metatarsus IV, much denser in females ( Fig. 1 A–B) than in males ( Figs 2 I–J, 5I –J, 8J–L). Scopular setae hairbrush-shaped ( Fig. 1 D). Leg tarsi mostly spinose (except for tarsi I–II of males), in males all pseudosegmented (i.e., median part lightly pigmented except for a normally pigmented dorsal stripe, Fig. 8 L). Tarsal organ low, cowpat-shaped ( Fig. 1 E–F). Paired leg claws with several unequal teeth in one row; unpaired claws bare. Palpal organ with a more or less distinctly divided distal hematodocha not reaching base of embolus, and with a more or less distinctly developed para-embolic apophysis ( Figs 2 H, 4A–B, 5E, G–H, 7A–B, 8G–H, 10A–C). Retroventral tibial apophysis of male palp more or less strongly developed, with ( Fig. 8 F–G) or without apical spicules ( Figs 2 F–H, 5E–H). Tibia I of males with two prolateral coupling spurs bearing one or two megaspines each ( Schwendinger 1991: figs 8–9), or without spurs and megaspines ( Figs 2 I, 5I, 8I); prolateral-distal spicules at base of distal-most coupling spur present ( Schwendinger 1991: fig. 9) or absent. Metatarsus I straight or bent, with or without prolateral process. Vulva with short genital atrium leading to two widely separated, strongly sclerotized sperm receptacles, each composed of a strongly pigmented, more or less enlarged base, of a strongly pigmented, more or less distinctly bent stalk pointing ectad (retrolaterad; Schwendinger 1991: fig. 12), entad (prolaterad) or dorsad ( Fig. 4 C), and composed of an unpigmented, rounded head being not or only slightly wider than the stalk ( Figs 4 C–G, 7C–E, 10D–G). Opisthosoma in posterior half of dorsal side with a pattern of dark transversal, medially interconnected bands (obscured by adpressed white hairs in living spiders; Figs 2 A–B, 3A–D, 5A–B, 6A–C, 8A–B, 9A–C).

Distribution. Specimens are currently available from all parts of Thailand except the south, from western Cambodia and from southern Laos ( Fig. 12 ). The genus probably also occurs in southern Myanmar.

Figures

FIGURE 1. Prothemenops irineae sp. n., SEM micrographs of female (not a paratype). A, dorsolateral view of metatarsus and tarsus of right leg I showing distribution of club-shaped trichobothria (no clavate trichobothria present). B, same in dorsodistal view. C, detail of club-shaped trichobothrium. D, scopular setae on metatarsus I. E, tarsal organ (with adhering dust particles) of right tarsus I. F, tarsal organ of right tarsus II.

FIGURE 2. Prothemenops irineae sp. n., male holotype (A, C, E – L) and female allotype (B, D). A – B, habitus, dorsal view. C – D, carapace, lateral view. E, eye group, dorsal view. F, distal part of right palp, retrodorsal view. G, same, proventral view. H, same, ventral view. I, tibia and metatarsus of right leg I, ventral view. J, tibia and metatarsus of right leg II, ventral view. K, labium and proximal part of left palpal coxa showing bristles with slightly swollen bases. L, recurved fovea with indentation in posterior margin.

FIGURE 4. Prothemenops irineae sp. n. A, right palpal organ of male holotype, retrolateral and slightly distal view. B, same, ventral and slightly distal view. C, left receptacle of exuvia of paratype, ental view (anterior is to the right, posterior to the left). D – G, vulvae of four female paratypes, dorsal view (D = allotype). Abbreviations: a = genital atrium, ae = apex of embolus, b = base of receptacle, be = base of embolus, dh = distal hematodocha, h = head of receptacle, pa = para-embolic apophysis, s = stalk of receptacle, st = subtegulum, t = tegulum, ue = uterus externus. Scale lines 0.1 mm (C), 0.5 mm (A – B, D – G).

FIGURE 5. Prothemenops khirikhan sp. n., male holotype (A, D – J) and female allotype (B – C). A – B, habitus, dorsal view. C, labium and palpal coxae, ventral view. D, eye group, dorsal view. E, distal part of right palp, retroventral view. F, same, retrodorsal view. G, same, ventral view. H, same, proventral view. I, tibia and metatarsus of right leg I, ventral view. J, tibia and metatarsus of right leg II, ventral view.

FIGURE 8. Prothemenops phanthurat sp. n., male holotype (A, C – D, F – L) and female allotype (B, E). A – B, habitus, dorsal view. C, carapace, lateral view. D, fovea, dorsal view. E, labium and palpal coxae, ventral view. F, distal part of right palp, retrodorsal view. G, same, ventral view. H, palpal organ, prolateral view. I, tibia of left leg I, ventral view. J, tibia and metatarsus of right leg I, ventral view. K, tibia and metatarsus of right leg II, ventral view. L, right tarsus I showing pseudosegmentation, prodorsal view.

FIGURE 12. Map of Southeast Asia (without southernmost Thailand and without peninsular Malaysia) showing localities of the three species treated in here (squares with numbers) and the currently known geographic range of the genus Prothemenops (grey area). 1, P. khirikhan sp. n.; 2, P. irineae sp. n.; 3, P. phanthurat sp. n.