Latest Articles from Zoosystematics and Evolution Latest 2 Articles from Zoosystematics and Evolution https://zse.pensoft.net/ Fri, 29 Mar 2024 02:36:59 +0200 Pensoft FeedCreator https://zse.pensoft.net/i/logo.jpg Latest Articles from Zoosystematics and Evolution https://zse.pensoft.net/ Bashimyzon cheni, a new genus and species of sucker loach (Teleostei, Gastromyzontidae) from South China https://zse.pensoft.net/article/116535/ Zoosystematics and Evolution 100(1): 309-324

DOI: 10.3897/zse.100.116535

Authors: Xiong Gong, E Zhang

Abstract: Bashimyzon, new genus, is here established for Erromyzon damingshanensis, and a new species of the genus is described from the You-Jiang of the Pearl River (=Zhu-Jiang in mandarin Chinese) basin in Guangxi Province, South China. This new genus has a small gill opening above the pectoral-fin base and short pectoral fins extending backwards short of pelvic-fin insertions, both characters combined to separate it from all currently-recognized gastromyzontid genera except Erromyzon and Protomyzon, but differs from the two genera in having a larger gap between the posterior edge of eye and the vertical through the pectoral-fin insertion and very small fleshy lobes posterior to the maxillary-barbel bases. It is further distinct from its most similar genus Erromyzon in having a relatively larger gill opening, fewer branched pectoral-fin rays folded against body, and more posteriorly placed pectoral fins with a shorter fin base. Bashimyzon cheni, new species, and B. damingshanensis, the single congeneric species, differ in number of lateral-line pored scales, body coloration, and cephalic contour, and also in substantial genetic divergence.

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Research Article Wed, 20 Mar 2024 10:26:16 +0200
The discovery of a microbialite-associated freshwater fish in the world’s largest saline soda lake, Lake Van (Turkey) https://zse.pensoft.net/article/62120/ Zoosystematics and Evolution 97(1): 181-189

DOI: 10.3897/zse.97.62120

Authors: Mustafa Akkuş, Mustafa Sarı, F. Güler Ekmekçi, Baran Yoğurtçuoğlu

Abstract: Lake Van is the largest saline soda lake in the world and one of the world’s few endorheic lakes of greater than 3,000 km2 surface area. Despite its huge size, no fish species have so far been known to permanently occur in this lake due to its extreme environmental conditions. Here, we report the discovery of a fish population that permanently inhabits some of the unique microbialites of the lake, at a maximum depth of 13 m and about 500 m offshore. We tested whether this is an undescribed species or a new occurrence of a known species. A molecular and morphological examination showed that the newly discovered fish represents an isolated population of Oxynoemacheilus ercisianus, the only nemacheilid loach native to the freshwater tributaries of the Lake Van endorheic basin. Our further hypotheses on the prediction that (a) stream fishes would have a more anterior placement of fins than lake fishes were supported; but, that (b) stream fishes would be more slender bodied than their lake conspecifics was not supported. The lake dwelling population also shows very small sequence divergence (0.5% K2P distance) to its stream dwelling conspecific in the mtDNA-COI barcode region. The notable morphological difference with minute molecular divergence implies that the newly discovered population might have lost its link to freshwater during desiccation and transgressional phases of the Lake Van, and has adapted to a life on the microbialites.

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Research Article Tue, 16 Mar 2021 10:29:23 +0200