Theridiosoma alboannulatum 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 alboannulatum Suzuki, Serita & Hiramatsu, 2020

Figs 12D , 13D-E , 15C

Theridiosoma alboannulatum Suzuki, Serita & Hiramatsu, 2020: 149, figs 2I-L, 4G-I, 6E-F, 12A-J, 13P (holotype male and paratypes from Iriomote Island, Japan; not examined).

Material examined.

Japan, Kurima Is. (Okinawa Prefecture): 2 ♂, Miyakojima City, Shimojikuruma (24°43'29.2"N, 125°15'09.2"E, alt. 41 m),, 17 Nov. 2021, Y. Suzuki leg. Miyako Is. (Okinawa Prefecture): 3♂ 3 ♀, Miyakojima City, Hiraranishihara , grassland at roadside (24°49'53.5"N, 125°18'55.0"E, alt. 46 m), 24 Apr. 2022, Y. Suzuki leg. Kuroshima Is. (Okinawa Prefecture): 2 ♂ 1♀, Yaeyama District, Taketomi Town, edge of coastal forest besides Hokei beach (24°14'26.2"N, 123°59'32.7"E, alt. 0 m), 2 Nov. 2021, Y. Suzuki leg. Yonaguni Is. (Okinawa Prefecture): 1 ♀, Yaeyama District, Yonaguni Town, Yonaguni (24°27'58.8"N, 123°01'20.1"E, alt. 49 m), 12 Oct. 2021, Y. Suzuki leg. ; 2 ♂ 2♀, Yaeyama District, Yonaguni Town, Sonai Village (24°28'10.5"N, 123°00'31.7"E, alt. 19 m), 12 Oct. 2021, Y. Suzuki leg. ; 1 ♂ 1♀, Yaeyama District, Yonaguni Town , wetland beside secondary forest (24°27'16.3"N, 122°59'24.3"E, alt. 38m), 14 Oct. 2021, Y. Suzuki leg.

Note.

See diagnosis section for comparison with T. nigrivirgatum sp. nov.

Habitat.

This species inhabits grasslands, bushes, and secondary forests. Spiders were collected from the basal parts of grasses.

Web morphology.

The spider weaves a concave web between the grasses (Fig. 13D, E ).

Egg sac.

similar to that of T. nigrivirgatum sp. nov. (Fig. 15C ).

Distribution.

Japan (Miyako, Kurima, Iriomote, Kuroshima, and Yonaguni Islands; Fig. 11 ).

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 13. Web of Theridiosoma and Zoma spiders at Ryukyu Islands, Japan A-C web of Theridiosoma nigrivirgatum sp. nov. D-E web of Theridiosoma alboannulatum F-H web of Zoma dibaiyin. Abbreviations: RA radial anastomosis SS sticky spirals TL tension line.

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.