A New Bothriolepid Antiarch from the Middle Devonian in Luquan, Yunnan, South China and Its Stratigraphic and Biogeographic Significances

Chahuaqingolepis magniporus gen. et sp. nov., a new taxon of Bothriolepididae (Placodermi: Antiarcha), is described from the Middle Devonian in Luquan County, Yunnan Province, South China. The phylogenetic analysis shows that Chahuaqingolepis is the sister group of Wufengshania with the synapomorphy of the large obtected nuchal area. Together with the findings of other associated antiarchs including Dianolepis, Bothriolepis, and Hunanolepis, the new bothriolepid antiarch is assigned to the Bothriolepis sinensis-Hunanolepis fish assemblage, which characterizes the Eifelian of the Middle Devonian in South China. The fish-bearing Tanglishu Formation can be well correlated with the Tiao-majian Formation in Changsha, Shangshuanghe Formation and lower part of the Haikou Formation in Qujing, and Laohutou Formation in Shaoguan and Lechang areas. This discovery not only enriches the Middle Devonian diversity of bothriolepids, but also provides reliable paleoichthyological evidence on the division and correlation of the fish-bearing Devonian strata in South China and deepens the understanding of the biogeography of the Devonian bothriolepids.

Automated summary

A new species of Bothriolepididae, Chahuaqingolepis magniporus gen. et sp. nov., has been discovered in Luquan County, Yunnan Province, South China, during the Middle Devonian period. Phylogenetic analysis reveals that Chahuaqingolepis is closely related to Wufengshania and shares a synapomorphy of having a large obtected nuchal area. This discovery not only enhances the diversity of bothriolepids during the Middle Devonian, but also contributes to the understanding of the biogeography and correlation of Devonian fish-bearing strata in South China.