Project description:To approach the taxonomy of large and complex animal groups it is of advantage to focus on species groups with shared derived character state. We investigate the composition, morphological characteristics and relationships of and within the Schistura cincticauda species group, whose members are small freshwater fishes that inhabit streams and rivers in eastern Myanmar and western and southern Thailand. A phylogenetic analysis using molecular genetic markers demonstrated the monophyly of this group; a combined genetic and morphological analysis revealed the inclusion of at least twelve species. They share the presence of a pair of black marks on the lower lip, one on each side of the median interruption (these marks may be reduced to few melanophores or even missing in some individuals). Additionally, all species share a small body size (max. 60 mm SL), an incomplete lateral line reaching at most to vertical through anal-fin base, and the absence of sexual dimorphism. Each of the 12 species is diagnosed by a unique combination of character states in fin ray numbers, anus position, presence/absence of an axillary pelvic lobe, and colour pattern. The distribution areas of several species overlap and five cases of syntopic occurrence are known. Five unnamed species are described herein.

| S-EPMC10562404 | biostudies-literature

Project description:Complete mitochondrial genome of Schistura yingjiangensis

| PRJNA1123854 | ENA

Project description:Complete mitochondrial genome of Schistura callichroma

| PRJNA1123853 | ENA

Project description:Complete mitogenome sequnece of Schistura polytaenia

| PRJNA1059148 | ENA

Genetic legacy of tertiary climatic change: a case study of two freshwater loaches, Schistura fasciolata and Pseudogastromyzon myersi, in Hong Kong.

Project description:The high biodiversity and strong population structure of freshwater fauna has often been attributed to historical geological and climatic alterations. The impact of these historical changes on obligate freshwater species on a small geographical scale has not been well understood due to the lack of fine-scale comparative phylogeographic studies. Strong population structure has been reported in a goby and a caridean shrimp in Hong Kong, a small but highly developed city in South China, but the common drivers of population differentiation in freshwater fauna in this region remain unclear. This study examined the fine-scale phylogeographic patterns of two freshwater loaches, Schistura fasciolata and Pseudogastromyzon myersi in Hong Kong, using sequence data of mitochondrial control region and two nuclear markers (interphotoreceptor retinoid binding protein gene 2 and ribosomal protein S13 gene). Results show that they exhibit pronounced population structure as supported by high and significant ΦST. Phylogenetic analyses based on the control region reveal six and three distinct lineages in S. fasciolata and P. myersi, respectively. Phylogeographic structure of both species generally follows the paleodrainage pattern, though P. myersi shows a shallower structure on the Mainland, perhaps due to their higher mobility. Most of these lineages diverged during the Pliocene and Late Pleistocene, a period with marked sea-level fluctuations. In a broader context, this suggests that sea-level fluctuation played an important role in shaping even the fine-scale population structure of freshwater fish in South China, implying that the genetic diversity of this fauna may be higher than expected.

| S-EPMC5637367 | biostudies-literature

Snail ChIP-chip on Ciona intestinalis embryo (early gastrula)

Project description:A genomic overview of in vivo binding of a transcription factor Snail in the ascidian early gastrula embryo.

2010-03-09 | GSE17691 | GEO