This will likely be exacerbated by the synergy between various anthropogenic impacts. SE Asia's fresh waters are expected to be under increasing pressure from the region's rapidly growing human population. This chapter focuses on changes due to anthropogenic activities, invasive fish species and changes in biodiversity in freshwater lakes and rivers in South East Asia. 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. Using data on molecular phylogenetics, genetic diversity and shell morphology, we provide a more inclusive species concept for S. Shell shape variation shows no clear separations and shows environmental plasticity. Genetic and shape variations were not congruent, suggesting that minor variations in shell shape do not indicate distinct Sinotaia species. quadrata populations in both China and Japan. We used microsatellite markers and landmark-based geometric morphometric analysis to examine the genetic differentiation and shell shape variation of S. The combination of phylogenetic and shape variance data suggests that seven currently recognized species of Sinotaia should be synonymized with S. We also compared the shell outline morphology of type material of most species in the genus Sinotaia from the original literature. quadrata based on the 16S rRNA and cytochrome c oxidase subunit I genes to test which classifications are robust using modern data and interpretation. To clarify relationships in this common and significant member of the freshwater benthos, we reconstructed a phylogeny for species related to S. 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. It follows that opportunity for rapid radiative evolution is of very great importance in the evolution of higher categories, and that such opportunity still may occur from time to time through geological changes.The taxonomy of species in the caenogastropod genus Sinotaia (Viviparidae: Bellamyinae) has been a complex and controversial issue since the 19th century. It is suggested that the origin of the excessively rich characid fauna of the Amazon River, and of the striking forms and groups of deep-sea fishes, has been due to similar tachytelic or quantum evolution. They have unquestionably already done so in the older lake-fish faunas, where certain endemic Tanganyika and Baikal genera are worthy of subfamilial or familial rank. The latter are often capable of becoming the founders of new genera, families, or perhaps even higher categories, at new adaptive levels. The evolution of lake-fish faunas is compared to that of island faunas, and to the evolution of any groups newly admitted to extensive areas where competition is light or absent, and shown to be essentially similar in the relatively rapid production of supralimitally specialized forms. A single preadapted fish family represented in the surrounding fluviatile fish fauna assumes dominance in the evolution of large endemic lake fish faunas. The stages of endemic lake-fish evolution are illustrated by examples, the youngest being the American Great Lakes, the oldest Lake Baikal. Supralimital specializations are shown to be very characteristic if not invariable features of all large, older, endemic lake-fish faunas some are so distinctive as to provide characters worthy of family rank. Certain specializations of the endemic Lanao genera are paralleled or approached by no others in the large, widespread family Cyprinidae because they transcend the morphological limits of all non-Lanao cyprinids, these are termed supralimital specializations. The distributional facts permit the identification, beyond reasonable doubt, of the single, still-existing, ancestral species that gave rise to the entire endemic fish fauna. The endemic fish fauna of Lake Lanao, all belonging to the family Cyprinidae, consisting of a species flock of 13 species and five species referred to four endemic genera, has evolved in a relatively short time, possibly as little as 10,000 years.
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