Molecular and morphological evidence for a unified, inclusiveSinotaia quadrata(Caenogastropoda: Viviparidae: Bellamyinae)

Abstract

The taxonomy of species in the caenogastropod genus Sinotaia (Viviparidae: Bellamyinae) has been a complex and controversial issue since the 19th century. Sinotaia quadrata, the type species of Sinotaia, comprises many named forms and transitions between them, and the taxonomic validity of some species similar to S. quadrata also requires clarification. To clarify relationships in this common and significant member of the freshwater benthos, we reconstructed a phylogeny for species related to S. quadrata based on the 16S rRNA and cytochrome c oxidase subunit I genes to test which classifications are robust using modern data and interpretation. We also compared the shell outline morphology of type material of most species in the genus Sinotaia from the original literature. The combination of phylogenetic and shape variance data suggests that seven currently recognized species of Sinotaia should be synonymized with S. quadrata. We used microsatellite markers and landmark-based geometric morphometric analysis to examine the genetic differentiation and shell shape variation of S. quadrata populations in both China and Japan. Genetic and shape variations were not congruent, suggesting that minor variations in shell shape do not indicate distinct Sinotaia species. Shell shape variation shows no clear separations and shows environmental plasticity. Using data on molecular phylogenetics, genetic diversity and shell morphology, we provide a more inclusive species concept for S. quadrata. This provides a basis to formally revise this taxon and the seven closely related nominal species that are widely distributed in China and East Asia.

Host species of freshwater snails within the same freshwater ecosystem shapes the intestinal microbiome

“…In this study, SMRT sequencing of full-length 16S rRNA genes was used to compare the gut microbiota of three species of wild herbivorous snails living in the same freshwater environment. Although three snail species, namely Sinotaia quadrata (SQ), Boreoelona ussuriensis (BU) and Radix plicatula (RP), are common in China (Wu et al, 2017;Ye et al, 2021); however, their intestinal microbial communities have not yet been reported. Through the successful identification of a number of bacteria up to the species level, this work yielded distinct gut microbial community profiles for the three snail species.…”

Metabolomics revealed that toxic cyanobacteria stress reduced the flavor quality of Bellamya aeruginosa

“…Bellamya aeruginosa (Gastropoda: Probranchia), is a widespread viviparid freshwater snail species that is distributed across East Asia (Qiu et al, 2017). It is also invasive in other regions, such as Europe and South America (Ye et al, 2021). Because of its delicious meat and high nutritional value, B. aeruginosa has been consumed as a delicacy and medicinal food since ancient times (Mak Sau-Wa, 2022).…”