Theridiosoma dissimulatum Suzuki, Serita & Hiramatsu, 2020

Suzuki, Yuya, Hiramatsu, Takehisa & Tatsuta, Haruki, 2022, Two new species and a new genus of ray spiders (Araneae, Theridiosomatidae) from the Ryukyu Islands, southwest Japan, with notes on their natural history, ZooKeys 1109, pp. 67-101 : 67

Theridiosoma dissimulatum Suzuki, Serita & Hiramatsu, 2020

Figs 11 , 12A , 15B

Theridiosoma dissimulatum Suzuki, Serita & Hiramatsu, 2020: 137, figs 1E-H, 3D-F, 5C, D, 8A-J, 9A-P, 13E-H (holotype male and paratypes from Amami Island, Japan; not examined).

Material examined.

Japan, Amami Is. (Kagoshima Prefecture): 1 ♀, Amami City, Nase-uragami Town (28°23'55.6"N, 129°32'27.5"E, alt. 139 m), 1 Jul. 2021, Y. Suzuki leg. ; 4 ♀, Amami City, Sumiyo Town, Nishinakama , Santaro-toge Pass (28°15'48.7"N, 129°25'09.0"E, alt. 141 m), 6 May 2021, Y. Suzuki leg. ; 1 ♀, Ôshima District, Yamato Village, Ôganeku, Materiya-no-taki Waterfall (28°19'04.4"N, 129°21'08.2"E, alt. 176 m), 4 Jul. 2021, Y. Suzuki leg. Okinoerabu Is. (Kagoshima Prefecture): 2 ♂ 4 ♀, Ôshima District, China Town, Tokudoki (27°21'34.5"N, 128°33'02.8"E, alt. 134 m), 8 Dec. 2021, Y. Suzuki leg. Okinawa Is. (Okinawa Prefecture): 2 ♂ 3 ♀, Naha City, Shuri-sueyoshi Town, Sueyoshi-koen Park (26°13'39.6"N, 127°42'55.3"E, alt. 25 m), 7 Mar. 2021, Y. Suzuki leg. ; 2 ♀, Kunigami District, Ôgimi Village, Nerome (26°40'49.7"N, 128°08'01.1"E, alt. 128 m), 14 Apr. 2021, Y. Suzuki leg. ; 1 ♀, Kunigami District, Ôgimi Village, Ôgimi (26°40'57.9"N, 128°08'21.6"E, alt. 311 m), 15 May 2021, Y. Suzuki leg. Iriomote Is. (Okinawa Prefecture): 1 ♂ 3 ♀, Yaeyama District, Taketomi Town, Haiminaka , Otomi-rindo Path (24°17'52.6"N, 123°52'47.3"E, alt. 18 m), 30 Apr. 2021, Y. Suzuki leg. ; 1 ♂ 3 ♀, Ôtomi-daiichi-do Cave (24°17'31.0"N, 123°52'45.7"E, alt. 30 m), 1 May 2021, Y. Suzuki leg.

Remarks.

This species can easily be distinguished from T. nigrivirgatum sp. nov. by the presence of a conductor projection on the male palp and a heart-shaped invagination with a pair of spurs on the posterior margin of the female epigynal plate ( Suzuki et al. 2020). Refer to the description in Suzuki et al. (2020) for further morphological information.

Distribution.

Japan (Amami, Okinoerabu, Okinawa, Ishigaki, and Iriomote Islands; Fig. 11 ).

Habitat.

This species was collected from dim moist forests, especially from locations beside streams (Fig. 12A ).

Web morphology.

Theridiosoma dissimulatum weaves a concave orb web and drags a tension line with the forelegs.

Egg sac.

pale reddish brown and spherical with a long horizontal line and a short stalk (Fig. 15B ).

Figures

Figure 11. Distribution of theridiosomatid species in the Ryukyu Islands, Japan.

Figure 12. Habitats of theridiosomatid species in Ryukyu Islands A streamside in dim forest at Iriomote Island B forest floor of secondary forest at Kume Island C grassland at Kume Island D grassland at Yonaguni Island E crevices on limestone rocky wall at Iriomote Island.

Figure 15. Egg sacs of theridiosomatid species A egg sac of Theridiosoma nigrivirgatum sp. nov. (cap opened) B egg sac of Theridiosoma dissimulatum C egg sac of Theridiosoma alboannulatum D-E egg sac of Sennin tanikawai sp. nov.