Rhopalopsole basinigra Yang & Yang, 1995

(Figs. 1–3)

Rhopalopsole basinigra Yang & Yang, 1995: 20; Qian & Du, 2012: 3; Yang & Du, 2021: 486.

Rhopalopsole duyuzhoui Sivec & Harper, 2008: 111; Yang & Du, 2021: 486.

Rhopalopsole trichotoma Yang & Du, 2021 . In: Yang et al. 2021: 146. syn. nov.

Rhopalopsole wulingensis Sivec & Shimizu, 2008 . In: Sivec et al. 2008: 97. syn. nov.

Material examined. Rhopalopsole trichotoma Yang & Du, 2021 . syn. nov.: Zhejiang Province, Qingyuan, Baishanzu, light trap, 550 m, N27.764444, E119.206436, 1994.IV.10, leg. Hong Wu.

Rhopalopsole wulingensis Sivec & Shimizu, 2008, syn. nov.: 2 topotype males, (CAU), China, Taiwan, Nantou County, Lianhuachi, 675 m, N23.923625, E120.891292, 2010.XI.11, leg. Ding Yang.

Rhopalopsole basinigra Yang & Yang, 1995: 54 males (teneral), Guizhou Province, Zunyi, Sanchahe, 2012. III.29, N28.498211, E 106.406611, leg. Weihai Li.

Distribution. China (Fujian, Guizhou, Shaanxi, Taiwan, Zhejiang).

Remarks. Although with typical characters of R. basinigra, the single male from Baishanzu of Zhejiang (type locality of R. duyuzhoui) was previously identified as R. duyuzhoui as a topotype because the top view of epiproct of R. basinigra was unknown in previous studies. The male is fully aged and shows identical head patterns and terminal characters of R. trichotoma with variations on the pigmentation of tergum 9 (which is typical for R. basinigra) and a darkly pigmented central plate (Fig. 1b). The original dorsal view of epiproct of holotype of R. trichotoma (figs. 5b & 6a, Yang et al. 2021) is identical with the top view (Figs. 1b & 1e, present study), plus the true dorsal aspect (Fig. 1g) is identical to R. basinigra reported from the Guizhou Province (fig. 4a, Yang & Du, 2021). This difference of viewpoint can be due to the moveable hinge of base of epiproct in different males as shown below in Fig. 3, in different individuals from Guizhou Province, and the position of epiproct can be also changed because of treatment of potassium hydroxide.

We checked two topotype males of R. wulingensis syn. nov. which was originally said to be closely related to R. trichotoma and found that one of them also has a similar central plate to R. trichotoma (Fig. 2a), which previously had been considered a diagnostic characteristic by Yang et al. (2021). The pigmentation of tergum 9 of R. wulingensis syn. nov. is indistinct (Fig. 2a), as in holotype of R. trichotoma (fig. 5b in Yang et al. 2021). These differences we considered herein as intraspecific variations related to age or degree of sclerotization. The trilobed epiproct in top and dorsal views is consistent with R. basinigra, especially with the populations of Guizhou (comparing Fig. 2b–d and Figs. 3a–g of the present study with figs. 4a–b in Yang & Du 2021).

We also checked the sensilla basiconica patch of Guizhou males that is invisible under light microscopy (Fig. 3a). The microphotograph (Fig. 3f) shows that the patch of sensilla basiconica forms well even in teneral adults. The pigmentation of tergum 9 in these males are indistinct thus we also consider as variations.

Overall, we considered these characters as intraspecific variations, and we therefore place these two species as junior synonym of R. basinigra .