Pharta bimaculata Thorell, 1891

Dhiya'ulhaq, Naufal Urfi, Benjamin, Suresh P., Buchori, Damayanti, Hidayat, Purnama, Scheu, Stefan & Drescher, Jochen, 2025, Expanding the taxonomy of crab spiders (Araneae, Thomisidae) in Sumatra: a new genus, five new species, and regional records, ZooKeys 1241, pp. 205-246 : 205-246

Pharta bimaculata Thorell, 1891

Figs 18 , 19 , 20

Pharta bimaculata Thorell, 1891: 85; Benjamin 2011: 18, figs 5 E, 48 A – D.

Sanmenia kohi Ono, 1995: 162, figs 7–15.

Material examined.

Indonesia – Jambi Province • 1 ♂, 1 ♀; Sarolangun, Air Hitam, Lubuk Kepayang ; 02°04'15.2"S, 102°47'30.8"E; elev. 54 m; 5 Jun. 2013; J. Drescher leg.; canopy fogging in oil palm plantation; GOET 2013_BO 3.2_AraThom 067 N_002–003 (to be transferred to MZB) . • 1 ♂; same data as previous; ZMH ZMH - A 0031855 (GOET 2013_BO 3.2_AraThom 067 N_001) . 1 ♀; Muaro Jambi, Bahar Utara, Talang Bukit ; 01°52'41.8"S, 103°21'21.6"E; elev. 21 m; 17 Aug. 2013; J. Drescher leg.; canopy fogging in oil palm plantation; ZMH ZMH -A 0031856 (GOET 2013 _ HOr 2.2_AraThom 067 N_001) . • 1 ♀; Batang Hari, Bajubang, Sungkai ; 01°51'39.4"S, 103°18'19.0"E; elev. 42 m; 19 Aug. 2013; J. Drescher leg.; canopy fogging in oil palm plantation; GOET 2013_HOr 3.1_AraThom 067 N_001 (to be transferred to SMF) .

Description.

Male (2013_BO 3.2_AraThom 067 N_001; Figs 18 , 20 A – C ). Total length 2.54. Carapace length 1.25; width 1.25. Abdomen length 1.29; width 1.10. Diameter of eyes: AME 0.04; ALE 0.09; PLE 0.09; PME 0.07. Interdistances between eyes: AME – AME 0.07; AME – ALE 0.05; ALE – ALE 0.22; PME – PME 0.09; PME – PLE 0.11; ALE – PLE 0.10; AME – PME 0.13; PLE – PLE 0.43. Leg measurements: leg I 5.30 (1.46, 0.48, 1.52, 1.20, 0.64); leg II 4.95 (1.39, 0.42, 1.46, 1.14, 0.54); leg III 2.64 (0.79, 0.31, 0.69, 0.50, 0.35); leg IV 2.86 (0.88, 0.23, 0.77, 0.61, 0.37). Carapace pear-shaped, yellow, with a thin, black border; cephalic region with a pair of faint, diagonal, red stripes that cross the eyes; AER recurved; PER recurved. Leg I dark brown; leg II paler than leg I; legs III and IV pale yellow. Abdomen oval, cream coloured with a pair of large red spots in the middle and a smaller pair anteriorly, as well as faint small red dots all over. Palp (Figs 18 D – F , 20 A – C ) as described in Ono (1995) under Sanmenia kohi .

Female (2013_BO 3.2_AraThom 067 N_003, Figs 19 , 20 D, E ). Total length 2.82. Carapace length 1.39; width 1.45. Abdomen length 1.43; width 1.30. Diameter of eyes: AME 0.04; ALE 0.11; PLE 0.11; PME 0.07. Interdistances between eyes: AME – AME 0.08; AME – ALE 0.05; ALE – ALE 0.25; PME – PME 0.10; PME – PLE 0.11; ALE – PLE 0.11; AME – PME 0.15; PLE – PLE 0.46. Leg measurements: leg I 5.33 (1.53, 0.59, 1.61, 1.14, 0.46); leg II 5.18 (1.56, 0.53, 1.55, 1.08, 0.46); leg III 2.67 (0.82, 0.31, 0.68, 0.48, 0.38); leg IV 3.03 (0.94, 0.31, 0.82, 0.54, 0.42). Habitus as in male, except the following: red carapace markings are more prominent and reach the middle of carapace. Small red dots on the abdomen are much more prominent. Epigynum: CO positioned roughly in the middle of spermatheca, on the inner margin, connected to a long horizontal fold. Spermatheca oval.

Distribution.

Singapore; Indonesia (Sumatra: Jambi Province; new record) Fig. 29 .

Variation.

Certain specimens have less vibrant markings on the carapace and abdomen (Fig. 19 D ).

Remarks.

The male specimen described here aligns perfectly with the characteristics of the genus, confirming the associated female’s accuracy. However, the genitalia of the female specimen described by Benjamin (2011: fig. 48 C, D) does not align with the female described in this study. Namely, it possesses a ‘ ring’ encircling the vulva, and the horizontal fold is noticeably lacking. Furthermore, the male and female specimens described by Benjamin (2011) were not collected during the same sampling event, suggesting a possible mismatch between them. Given that this is the type species of the genus and the type specimen is a juvenile, minimising taxonomic confusion is essential. Therefore, the current material will be described as it is, while acknowledging the uncertainties. To resolve this issue definitively, we propose awaiting additional specimens from Singapore, the terra typica. Broader sampling will help clarify the taxonomic placement and relationships, providing a more accurate and comprehensive understanding of this taxon in future.

Figures

Figure 18. Pharta bimaculata Thorell, 1891, male (2013 _ BO 3.2 _ AraThom 067 N _ 001) A, B habitus A dorsal view B ventral view C eye region, frontal view D – F left palp D prolateral view E ventral view F retrolateral view. Scale bars: 1 mm (A, B); 0.2 mm (C); 0.1 mm (D – F).

Figure 19. Pharta bimaculata Thorell, 1891 A, B, D – F female (2013 _ BO 3.2 _ AraThom 067 N _ 003) A, B habitus A dorsal view B ventral view D – F epigynum D ventral view E cleared, ventral view E cleared, dorsal view C female (2013 _ HJ 4.2 _ AraThom 067 N _ 001), habitus, dorsal view. Scale bars: 1 mm (A – C); 0.1 mm (D – F).

Figure 20. Pharta bimaculata Thorell, 1891 A – C male (2013 _ BO 3.2 _ AraThom 067 N _ 001), left palp A ventral view B retrolateral view C palpal tibia, retrolateral view D, E female (2013 _ BO 3.2 _ AraThom 067 N _ 003), epigynum D ventral view E dorsal view. Abbreviations: C = conductor; CO = copulatory opening; E = embolus; FD = fertilisation duct; MA = median apophysis; RTA = retrolateral tibial apophysis; S = spermatheca; VTA = ventral tibial apophysis. Scale bars: 0.1 mm.

Figure 29. Distribution of examined Thomisidae species from the Epidius clade (sensu Benjamin, 2011) prior to the present study, as well as the sampling location of the current study in Jambi Province, Sumatra, Indonesia (green flag). The new genus and the five new species described in the present study are all from the same study location, i. e., a replicated plot design across lowland rainforest, ‘ jungle rubber’ (rubber agroforestry), and smallholder monoculture plantations of rubber and oil palm in Jambi’s lowlands (Drescher et al. 2016).