|Habitus of Theridiosoma species when alive. |
A-D, Theridiosoma epeiroides; E-H, T. dissimulatum sp. nov.;
I-L, T. paludicolum; M-O, T. fulvum. P, T. alboannulatum sp. nov.
in Suzuki, Serita & Hiramatsu, 2020.
Japanese spiders of the genus Theridiosoma (Araneae: Theridiosomatidae) were revised with redescription of T. epeiroides Bösenberg & Strand 1906 and description of four new species, namely: T. dissimulatum sp. nov., T. paludicolum sp. nov., T. fulvum sp. nov., and T. alboannulatum sp. nov. The internal morphology of the female genitalia of T. epeiroides is illustrated in this study for the first time. Males of the new species can be distinguished from their congeners by the morphology of the embolic apophyses or the posterior edge of the embolic division on the male palp. Females of the former three species can be differentiated from their related species by the shape of the contour formed by interior edges of a pair of sclerotized processes on the posterior edge of the genital plate. The latter species can be distinguished from the allied species by the angular lateral corners of the genital plate and overall shape of the genitalia (longer than wide).
Keywords: Conductor projection, embolic apophysis, epigyne, morphology, new species, process, taxonomy
Yuya Suzuki, Ryohei Serita and Takehisa Hiramatsu. 2020. Japanese Spiders of the Genus Theridiosoma (Araneae: Theridiosomatidae) with the Description of Four New Species. Acta Arachnologica. 69(2): 133–150. DOI: 10.2476/asjaa.69.133