On the validity of Hebius sauteri maximus (Malnate, 1962) (Squamata, Natricidae), with the redescription of H. maximus comb. nov. and H. sauteri (Boulenger, 1909)

Abstract

Hebius sauteri (Boulenger, 1909) has been long recognized as a widely distributed species with three subspecies, namely Hebius sauteri sauteri from Taiwan Island and southeastern China, Hebius sauteri bourreti (Malnate, 1962) from northern Vietnam, and Hebius sauteri maximus (Malnate, 1962) from Sichuan, southwestern China. However, the validity of these subspecies of the H. sauteri complex has not been evaluated. In the current study, we re-evaluate the taxonomic status of H. s. maximus based on morphological and molecular evidence. Molecular phylogenetic results indicate that H. s. maximus is a distantly diverged clade with respect to H. s. sauteri, and that H. s. maximus is morphologically distinguishable from the nominative subspecies. Therefore, our results support the validity of H. s. maximus and we elevate it to full species status, namely Hebius maximuscomb. nov. The distribution range of H. sauteri is revised according to our proposed taxonomic change. Furthermore, detailed redescription, natural history, and coloration of both H. sauteri and H. maximus and comments on the validity of H. s. bourreti are also provided.

A new species of the genus Hebius (Squamata, Natricidae) from Yunnan, China

“…Morphological characters were described for the newly collected specimen and compared with other key references ( Günther 1875 ; Wall 1910 ; Wall 1925 ; Bourret 1934 ; Taylor 1934 ; Gressitt 1937 ; Smith 1940 ; Dowling 1951a , 1951b ; David and Das 2003 ; Zhao 2006 ; David and Vogel 2010 ; Guo et al 2014 ; Liu et al 2018 ; Ren et al 2018 ; Purkayastha and David 2019 ; Zhou et al 2019 ; Ziegler et al 2019 ; David et al 2021 ; Huang 2021 ; Hou et al 2021 ; Hauser et al 2022 ; Li et al 2022 ; Ma et al 2023 ; Xu et al 2023 ). The measurements and scale counts followed those of Dowling (1951a , 1951b ), Zhao (2006) , and Huang (2021) .…”

“…Currently, there are 51 valid species in the genus Hebius , of which 26 are known to occur in China ( Hauser et al 2022 ; Li et al 2022 ; Ma et al 2023 ; Xu et al 2023 ; Uetz et al 2024 ). Furthermore, recent morphological and molecular phylogenetic analyses of Hebius have shown that the weak species delimitation within this genus may be due to underestimated diversity ( Guo et al 2014 ; Kizirian et al 2018 ; Liu et al 2018 ; Zhou et al 2019 ; Hou et al 2021 ).…”