Oedothorax Bertkau 1883

Genus Oedothorax Bertkau, 1883 (aheǥ) Type species. Neriene gibbosa Blackwall, 1841. Remark. Genus Oedothorax comprises 38 species (including eleven species known from males and nine from females only) distributed in Indonesia, Malaysia (Borneo), and Holarctic, of which four species have been reported from China (Hebei, Hubei, Hunan, Guizhou, Jilin, Liaoning, Shanxi, Xinjiang, Yunnan and Zhejiang) (Li & Lin 2016, WSC 2025). The genus Oedothorax Bertkau, 1883, is poorly delimited, as evidenced by the transfer of 125 formerly member of genus have been transferred to over a dozen other genera (WSC 2025). This taxonomic instability reflects historical confusion in defining the genus synapomorphies and misclassifications. Recently, Lin et al. (2022) conducted a taxonomic revision and cladistic analysis based on morphological characters in an effort to clarify the genus boundaries. However, the genus remains problematic due to overlapping morphological traits with related genera (e.g., Callitrichia, Mitrager, Nasoona). Many species now reside in distantly related groups, underscoring the need for further phylogenetic study to stabilize Oedothorax and its allies. Currently, only a small core of species (e.g., O. agrestis, O. apicatus, O. gibbosus) remains in the genus, while approximately 24 out of 38 species have been assigned to incertae sedis (Lin et al. 2022). This taxonomic disarray highlights the challenges of delineating Oedothorax without robust synapomorphies or molecular data.