Platythomisus octomaculatus (C. L. Koch, 1845)

Lin, Yejie, Koh, Joseph K. H., Shao, Lili & Li, Shuqiang, 2019, Description on two species of genus Platythomisus (Araneae, Thomisidae) from China and Singapore, ZooKeys 852, pp. 73-84 : 73

Platythomisus octomaculatus (C. L. Koch, 1845) Figs 1 A–C, 2A, C, 3A, B, 4 A–D, 5A, B, 6

Thomisus 8-maculatus C.L. Koch 1845: 55, fig. 990 (♀).

Platythomisus phryniformis Doleschall 1859: 60 pl. 3, fig. 10 (♀).

Platythomisus octomaculatus van Hasselt 1882: 42, pl. 3, fig. 4 (♀); Simon 1895: 1017, fig. 1076 (♀).

Type material.

The holotype of P. octomaculatus was not examined as it could not be located in any of the databases of all the major museums in Europe.

Specimens examined.

♂ (LKCNHM), Singapore, Pasir Ris Road, Pasir Ris Nature Park, mangrove foliage, 09.X.2018, J. Koh leg.; ♀ (LKCNHM), Singapore, Neo Tiew Crescent, Sungei Buloh Wetland Reserve, mangrove foliage, 01°26'49"N, 103°43'45"E, 20.IV.2016, M. Tan leg. ♀ (LKCNHM), Singapore, Neo Tiew Crescent, Sungei Buloh Wetland Reserve, mangrove foliage, 01°26'53"N, 103°43'42"E, 13.I.2013, J. Koh leg.

Diagnosis.

See diagnosis of the species Platythomisus xiandao sp. nov.

Description.

Male (Figs 1 A–C, 2A, C, 4C, D, 5B): total length 3.72, carapace 1.62 long, 1.5 wide, opisthosoma 2.18 long, 1.52 wide. Carapace reddish brown. Eye region orange, AER and PER recurved. Eye sizes and interdistances: AME 0.06, ALE 0.09, PME 0.04, PLE 0.08, AME–AME 0.26, AME–ALE 0.20, PME–PME 0.37, PME–PLE 0.28, AME–PME 0.17, ALE–PLE 0.19. Clypeus 0.13 high, red. Chelicerae red, with ridge, without any teeth. Endites and labium red anteriorly and black posteriorly. Sternum black, with sparse hairs. Legs white, coxae faint black, tarsi, metatarsi and tibiae have a longitudinal black line dorsally each. Legs translucent when alive. Leg I: 6.45 (2.05 + 2.26 + 1.23 + 0.91), leg II: 6.60 (2.18 + 2.35 + 1.19 + 0.88), leg III: 3.84 (1.34 + 1.44 + 0.54 + 0.52), leg IV: 3.56 (1.31 + 1.30 + 0.46 + 0.49). Leg formula: 2134. Opisthosoma broadly pentagonal, dorsum yellow-cinnamon, ventrum reddish-brown. Dorsum with three distinct black spots and four smaller faint brown spots, with red folds laterally, ventrum with a large shield-shaped black patch. Spinnerets black.

Male palp (Figs 1 A–C, 2A, C). Femur white. Tibia black, VTA club-shaped, with a thick bristle near the apex. ITA boot-shaped, terminally flat with a laterally pointing extension. RTA long, terminal slightly bent. Cymbium black. Tegulum flat, disk-shaped, with a tegular ridge. Embolus spiral, thin, the base of embolus arising from a 1:30- o’clock-position, the length of embolus to the length of embolus base 5:1 (Fig. 2A).

Female (Figs 3A, B, 4A, B, 5A) markedly larger and different from male. Total length 17.05, carapace 8.21 long, 7.63 wide, opisthosoma 10.00 long, 7.31 wide. Carapace yellow with three pairs of black spots. The anterior pair cover the ALE and PLE, adjacent to AME and PME; middle spots extremely small. AER and PER slightly recurved. Eye sizes and interdistances: AME 0.14, ALE 0.19, PME 0.10, PLE 0.16, AME–AME 1.14, AME–ALE 0.93, PME–PME 1.61, PME–PLE 1.01, AME–PME 0.54, ALE–PLE 0.42. Clypeus height 0.68, orange. Chelicerae orange, with ridge, margin has a thin brown ring pattern, without any teeth. Endites and labium orange. Sternum orange, with sparsely set hairs. Legs two-colored, with coxa, trochanter, femur and patella in orange, and metatarsus and tarsus black. Coloration of the tibiae varies: black in tibiae I and II, while orange in tibiae III and IV. Leg I: 26.84 (8.14 + 9.62 + 6.02 + 3.06), leg II: 27.24 (8.21 + 9.94 + 6.09 + 3.00), leg III: 15.64 (5.58 + 5.90 + 2.50 + 1.66), leg IV: 15.81 (5.32 + 6.47 + 2.47 + 1.55). Leg formula: 2143. Opisthosoma sub-rectangular with a bluntly pointed posterior end, yellow, laterally pleated. Dorsum with seven blue-grey spots, ventrum with an oblong black patch. Spinnerets black, surrounded by a narrow black ring.

Epigyne (Figs 3A, B) with atrium shaped like a funnel with a broad neck, the length of atrium to the middle width of the atrium 1:1.5, the length of anterior margin to the length of posterior margin 2:1. CD short, approximately half the length of the spermathecae. Spermathecae stout, with almost parallel sides anteriorly.

Intraspecific variations: While the holotype has eight spots on the dorsum, as illustrated by Koch (1845), mature specimens seen or photographed in Singapore, Brunei, Thailand, and East and West Malaysia possess only seven dorsal spots but with the eighth spot on the ventrum. In some juvenile females, there are only five dorsal spots on the opisthosoma. The number of spots on the carapace varies between two and four pairs in mature females. The general coloration of live male specimens varies from yellow to red.

Distribution.

The type locality “Ostindien”, meaning "East Indies", refers to Indonesia today. Within Indonesia, the species was recorded in Java as Platythomisus phryniformis by Doleschall (1859) and in Padang, Sumatra by Hasselt (1882). However, we failed to find any specimens of the species during field trips in the country. This species has been recorded in Singapore, Brunei, Thailand, and East and West Malaysia ( Koh and Leong 2014). A report of P. octomaculatus from Assam, India ( Yadav et al. 2017) is clearly misidentified. We suggest it may be P. xiandao sp. nov.

Natural history.

Individuals live among low-lying tree foliage in or around degraded forests and mangrove swamps. Eggs are laid between leaves and sealed with thick silk. The egg sacs are guarded by the mother until the spiderlings hatch in about 2 weeks.