Platythomisus xiandao, Lin, Yejie, Koh, Joseph K. H., Shao, Lili & Li, Shuqiang, 2019

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 xiandao sp. nov. Figs 1 B–D, 2B, D, 3C, D, 4 E–H, 5C, D, 6

Holotype.

♂ (IZCAS), China, Yunnan Prov., Jinghong City, Mount Jinuo, hatched from paratype egg sac. Hatched 12.X.2017, matured 10.IV.2018, C.T. Wei leg. Paratype: ♀ (IZCAS), same locality data as holotype, collected 06.X.2017, C.T. Wei leg.

Etymology.

The specific name is derived from the Chinese word " xiandao " (noun), the name of the Strategic Priority Research Program of the Chinese Academy of Sciences (CAS). The program has made it possible for the biodiversity research team in the CAS to remain as an integral cluster to fulfil all its ambitious goals.

Diagnosis.

Male of P. xiandao sp. nov. can be easily distinguished from that of P. octomaculatus by the length of embolus to the length of embolus base is 3:1 (Fig. 2B), but 5:1 in P. octomaculatus (Fig. 2A), the base of embolus arising from a 3:30- o’clock-position in P. xiandao sp. nov. (Fig. 1E), and 1:30- o’clock-position in P. octomaculatus (Fig. 1B); the atrium of P. xiandao sp. nov. is bell-shaped (Fig. 3C) while that of P. octomaculatus is funnel-shaped (Fig. 3A); the spermathecae of P. xiandao sp. nov. (Fig. 3D) are more slender than those in P. octomaculatus (Fig. 3B).

The two species can also be diagnosed by their somatic differences. The males of P. xiandao sp. nov. have seven black spots on the opisthosoma (Fig. 4G) and a reddish sternum (Fig. 4H); the males of P. octomaculatus have only three distinct black spots on the opisthosoma (Fig. 4C) and a black sternum (Fig. 4D). The females of P. xiandao sp. nov. have larger black patches on the carapace (Fig. 4A) and a black patch at the center of ventrum extending posteriorly to connect with the black area surrounding the spinnerets through a narrow neck (Fig. 4F), while the black patch at the ventrum of P. octomaculatus females is broadly oblong and well-separated from the spinnerets (Fig. 4B).

Description.

Male (Figs 1 D–F, 2B, D, 4G, H, 5D): total length 3.92, carapace 1.55 long, 1.38 wide, opisthosoma 2.40 long, 1.70 wide. Carapace red. Eye region orange, AER and PER recurved. Eye sizes and interdistances: AME 0.05, ALE 0.09, PME 0.03, PLE 0.06, AME–AME 0.24, AME–ALE 0.17, PME–PME 0.32, PME–PLE 0.28, AME–PME 0.13, ALE–PLE 0.19. Clypeus 0.13 high, red. Chelicerae red, with ridge, without any teeth. Endites and labium red. Sternum red, sparsely set hairs. Legs white, coxa black, tarsus, metatarsus, tibia, patella and femur of leg I and II have two black lines. Legs transparent when alive. Leg I: 5.73 (1.86 + 2.00 + 1.08 + 0.79), leg II: 6.04 (2.02 + 2.10 + 1.10 + 0.82), leg III: 3.20 (1.00 + 1.20 + 0.51 + 0.49), leg IV: 3.27 (1.21 + 1.11 + 0.46 + 0.49). Leg formula: 2143. Opisthosoma oval, white, dorsum cinnamon, ventrum reddish-brown. Opisthosoma dorsum with seven black spots, first one largest, lateral sides with red folds, ventrum reddish-brown, with a large shield-shaped black pattern. Spinnerets black.

Male palp (Figs 1 D–F, 2B, D). Femur white. Tibia black, VTA club-shaped, slightly bent, with a bristle near the apex. ITA boot-shaped, terminally flat with lateral extension. RTA long and thin, terminal slightly bent. Cymbium black. Tegulum flat, disk-shaped, with tegular ridge. Embolus slender and spiral, the base of embolus arising from a 3:30- o’clock-position, the length of embolus to the length of embolus base 3:1 (Fig. 2B).

Female (Figs 3C, D, 4E, F, 5C) distinctly different from male. Total length 13.01, carapace 5.20 long, 5.05 wide, opisthosoma 8.78 long, 6.35 wide. Carapace yellow with three pairs of big black subcircular patches. The anterior pair extend to the protruding ends on both lateral sides of the ocular tubercles, covering the ALE, PME and PLE, and adjoining the AME. The median pair of black disks smaller than the anterior and posterior pairs. AER and PER slightly recurved. Eye sizes and interdistances: AME 0.11, ALE 0.12, PME 0.05, PLE 0.09, AME–AME 0.81, AME–ALE 0.54, PME–PME 1.02, PME–PLE 0.71, AME–PME 0.37, ALE–PLE 0.36. Clypeus height 0.56, orange. Chelicerae orange, with ridge, margin has a black ring pattern, without any teeth. Endites and labium orange. Sternum orange, sparsely set hairs. Legs bicolored, coxa, trochanter, the femur of leg I and II black, the patella of leg I and II and the femur of leg III and IV orange with a black inverted triangle spot. Other legs orange. Leg I: 18.09 (5.70 + 6.41 + 3.96 + 2.02), leg II: 18.54 (5.96 + 6.54 + 4.00 + 2.04), leg III: 10.82 (3.64 + 4.04 + 1.88 + 1.26), leg IV: 11.16 (3.92 + 4.35 + 1.66 + 1.23). Leg formula: 2143. Opisthosoma pentagonal, yellow. Opisthosoma dorsum with seven black spots, with the largest in the anteriormost spot, lateral folded, ventrum yellow, with a shield-shaped black pattern coalescing with the black ring surrounding the black spinnerets.

Epigyne (Fig. 3C, D) with bell-shaped atrium, the length of atrium to the middle width of the atrium 1:1.4, the length of anterior margin to the length of posterior margin 1:1. CD short, about one-fourth the length of the spermathecae. Spermathecae comparatively slender, shaped like a sea cucumber or hot-dog sausage.

Distribution.

China (Yunnan).

Natural history.

Individuals of this species hide under the leaves.

Remarks.

Based on the 647 bp-aligned sequences, the COI uncorrected K2P-distance between P. octomaculatus and P. xiandao sp. nov. is 0.073. The result far exceeded the maximum value of intraspecific genetic distance for Thomisidae .