Nyctimus kinabaluensis Benjamin & Dhiya’ulhaq, 2025

Benjamin, Suresh P., Dhiya’ulhaq, Naufal Urfi, Deeleman-Reinhold, Christa, Buchori, Damayanti, Hidayat, Purnama, Scheu, Stefan & Drescher, Jochen, 2025, Taxonomic notes on the crab-spider genera Nyctimus Thorell, 1877 and Zametopina Simon, 1909 (Araneae, Thomisidae) with descriptions of six new species from Southeast Asia, ZooKeys 1255, pp. 95-125 : 95-125

Nyctimus kinabaluensis Benjamin & Dhiya’ulhaq sp. nov.

Figs 5 , 6 , 7

Etymology.

The specific epithet is derived from the name of the type locality.

Type material.

Holotype. Malaysia – Sabah State • ♂; Kinabalu National Park, Poring Hot Springs ; 05°59'N, 116°42'E; elev. 600–700 m; 27 Feb. 1996; A. Floren leg.; canopy fogging on Barringtonia tree, in primary forest; RMNH RMNH.ARA.17862 .

Other material examined.

Brunei – Tutong District • 1 ♀; Lamunin, Bukit Sulang ; 1982; N. Stork leg.; canopy fogging; RMNH RMNH.ARA.17859 . Indonesia – Sumatra, Jambi Province • 1 ♀; Sarolangun, Bukit Duabelas National Park ; 01°58'55.2"S, 102°45'02.6"E; elev. 73 m; 7 Oct. 2013; J. Drescher leg.; canopy fogging in rainforest; GOET 2013_BF 2.1_AraThom 004 N_001 (to be transferred to MZB) .

Diagnosis.

Males can be easily distinguished from all other congeners by the embolic base abruptly bent 90 ° towards the retrolateral side of the cymbium and the tapered, bent embolus (Fig. 7 A, B ). Females are distinguishable by the long, oval spermatheca (globular or short-oval in all other congeners; Figs 6 C, D , 7 C, D ).

Description.

Male ( holotype RMNH.ARA.17862 ; Figs 5 A, B , 7 A, B ). Total length 3.24. Prosoma length 1.61; width 1.50. Opisthosoma length 1.63; width 1.31. Diameter of eyes: AME 0.11; ALE 0.20; PLE 0.17; PME 0.08. Interdistances between eyes: AME – AME 0.44; AME – ALE 0.11; ALE – ALE 0.81; PME – PME 0.45; PME – PLE 0.36; ALE – PLE 0.21; AME – PME 0.17; PLE – PLE 1.15. Leg measurements: leg I 5.0 (1.5, 0.6, 1.3, 1.0, 0.6). Prosoma cuboid, almost as long as wide, dark reddish brown; surface weakly granulated; laterally adorned with long macrosetae, each arising from a small tubercle. Chelicerae and sternum coloured as prosoma. Endites brown with white tip. Front legs brown; back legs brown except for the white femora. Opisthosoma oval, greyish brown with white spots (most dense in the anterior half) and paired white bars in the middle; anteriorly with a white border; five large sigillae present, arranged in a triangular formation.

Palp (Fig. 7 A, B ): cymbium oval. Embolus elongated, tapering, with a 150 ° bend in the middle. Tegular hood small. RTA bilobed; ventral lobed very large, claw-shaped; dorsal lobe much smaller than ventral lobed, roughly triangular with an obtuse tip and a small triangular projection; VTA hook-shaped, small, attached medially on the RTA.

Female ( RMNH.ARA.17859 ; Figs 5 C , 7 C, D ). Total length: 3.38. Prosoma length 1.48; width 1.27. Opisthosoma length 1.90; width 1.70. Diameter of eyes: AME 0.07; ALE 0.17; PLE 0.14; PME 0.06. Interdistances between eyes: AME – AME 0.38; AME – ALE 0.12; ALE – ALE 0.74; PME – PME 0.39; PME – PLE 0.33; ALE – PLE 0.22; AME – PME 0.17; PLE – PLE 0.98. Leg measurements: leg I 4.6 (1.3, 0.4, 1.1, 1.0, 0.8). Habitus as in male.

Epigynum (Fig. 7 C, D ): exterior plate large, roughly square with rounded sides. Atrium oval. CO diagonally oriented, anteriorly facing. CD arched. Spermatheca long oval, with a slight bump anteriorly.

Distribution.

Brunei; Malaysia (Borneo: Sabah); Indonesia ( Sumatra: Jambi) (Fig. 19 ).

Figures

Figure 5. Nyctimus kinabaluensis Benjamin & Dhiya’ulhaq sp. nov., from Borneo. A. Male holotype (RMNH. ARA. 17862), prosoma, dorsal view; B. ibid., opisthosoma, dorsal view; C. Female (RMNH. ARA. 17859), habitus, dorsal view. Scale bars: 0.5 mm.

Figure 6. Nyctimus kinabaluensis Benjamin & Dhiya’ulhaq, sp. nov., from Sumatra. A. Female (2013 _ BF 2.1 _ AraThom 004 N _ 001), habitus, dorsal view; B. Prosoma, frontal view; C. Epigynum, ventral view; D. Epigynum, dorsal view, cleared. Scale bars: 1 mm (A); 0.5 mm (B); 0.2 mm (C, D).

Figure 7. Nyctimus kinabaluensis Benjamin & Dhiya’ulhaq, sp. nov., from Borneo. A. Male (RMNH. ARA. 17859), left palp, ventral view; B. ibid., retrolateral view; C. Female (RMNH. ARA. 17862), epigynum, ventral view; D. ibid., dorsal view. Abbreviations: CD = copulatory duct; CO = copulatory opening; E = embolus; RTA = retrolateral tibial apophysis; S = spermatheca; TH = tegular hood; VTA = ventral tibial apophysis. Scale bars: 0.2 mm.

Figure 19. Distribution of all described Nyctimus and Zametopina (Araneae: Thomisidae) species. Grey circles surrounding white dots indicate species collected from the same or very closely located sampling points in Brunei, Sabah (Malaysia), and Jambi (Indonesia).