Sphaerobelum Verhoeff, 1924

Genus Sphaerobelum Verhoeff, 1924 View in CoL

Type species.

Sphaerobelum clavigerum Verhoeff, 1924 View in CoL , by subsequent designation of Jeekel (1971: 28).

Other species included.

26 species (plus three described below: Verhoeff 1924; Attems 1938, 1953; Wongthamwanich et al. 2012; Semenyuk et al. 2018, 2020; Wesener 2019; Zhao et al. 2020, 2022; Rosenmejer et al. 2021; Bhansali and Wesener 2022; Srisonchai et al. 2023).

Distribution.

China (3 species), Laos (10 species), Thailand (7 species), and Vietnam (7 species).

Diagnosis.

A genus of Zephroniinae in which the posterior telopod has 4 telopoditomeres distal to the syncoxite, immovable finger apically uniquely enlarged and massively swollen (except for S. aesculus , S. meridionalis , and S. benqii , in which there is just a swollen spot). Anterior telopod either with 3 or 4 podomeres distal to syncoxite, with podomeres 3 and 4 simple, either completely fused, partly fused, or completely separated.

See more detail of diagnosis in Wongthamwanich et al. (2012), Wesener (2016), Semenyuk et al. (2018), and Srisonchai et al. (2024 b).

Remarks.

Wesener (2019) divided the genus into two main groups based on the modification of the mesal margin of the leg femur. The first group consists of species with either a flat margin or inconspicuous tiny teeth (hardly visible under a stereomicroscope); here, we refer to this as the ‘ unmodified femur. ’ The second group, the ‘ modified femur, ’ includes species with conspicuous teeth along the margin (easily visible under a normal stereomicroscope).

In Thailand, four previously recorded species ( S. aesculus , S. meridionalis , S. truncatum , and S. turcosa ), as well as the three new species described here, are assigned into the ‘ unmodified femur’ group, characterised by no or only inconspicuous teeth on the femur of the leg.