Comparative morpho-anatomy and mitochondrial phylogeny of Semisulcospiridae in Yunnan, south-western China, with description of four new species (Gastropoda : Cerithioidea)

Abstract

The taxonomic history of Chinese semisulcospirids is confusing. Originally placed in Melania by late 19th century authors, species have subsequently been dispersed into four different genera, i.e. Semisulcospira Böttger, 1886, Senckenbergia Yen, 1939, Hua Chen, 1943, and Namrutua Abbott, 1948; however, these placements were not conducted within a phylogenetic context. Based on examination of newly collected samples from the Chinese provinces Yunnan, Guizhou, Jiangxi, Anhui and Chongqing, we revised the systematics of the Chinese Semisulcospiridae based on comparative anatomy and mitochondrial phylogenetics. We have examined shell, radular, and reproductive features and employed Bayesian and Maximum Likelihood analyses of partial sequences of mitochondrial genes cytochrome c oxidase I and 16S rRNA to resolve the phylogenetic relationships. The results revealed that Semisulcospiridae is represented by three genera in China, which differ in their reproductive strategy, including Semisulcospira, which is viviparous and contains three species (S. ningpoensis, S. gredleri, and S. pleuroceroides); Hua, which is oviparous and contains 11 species; and Koreoleptoxis, which is oviparous and contains one species. Namrutua and Senckenbergia are identified here as junior subjective synonyms of Semisulcospira. All taxa recognised herein formed well differentiated clades in three mitochondrial phylogeny, and could be reliably distinguished by differences in shell shape and sculpture. Four new species of Hua are described from Yunnan Province. This is the first comprehensive study to review the taxonomy of semisulcospirids in China. These species are sensitive to water quality, and economic development and infrastructure expansion have negatively impacted many populations. We fear that some species may have disappeared before being investigated or described scientifically. Therefore, this research will hopefully inspire further studies and surveys to foster our understanding of freshwater gastropod diversity in China. http://zoobank.org/urn:lsid:zoobank.org:pub:EF2147FD-9EEE-4922-90DC-76651EF9E6AE