Description of the external morphological characters of the Turkestan gudgeon Gobiolepidolaemus (Gobionidae) from the Yrgaity River (Shu River basin).

Abstract

The article is devoted to the native fish species of Central Asia — the Turkestan gudgeon Gobiolepidolaemus — an inhabitant of the water bodies of Southern Kazakhstan. According to some researchers, various populations of this species are still poorly studied and may represent separate forms. In Kazakhstan water bodies, populations of the Talas, Shu, Sarysu and Karatau river systems were previously studied, but the available data on morphological variability are often incomplete. A more detailed study of individual populations is needed, based on freshly collected material and more accurate methods. The aim of the article was to describe the external morphological characteristics of the Turkestan gudgeon Gobiolepidolaemus (Gobionidae) from the Yrgaity River (right tributary of the Shu River). External morphological characters were studied on 21 specimens. A detailed description of the coloration, body proportions and fin shape, meristic characters (the number of scales and fin rays) is given, and for the first time for the Turkestan gudgeon, squamation on various areas of the body are described in detail. Three types of breast squamation, a specific feature of the Turkestan gudgeon, have been identified. A comparative analysis was carried out with literature data on Turkestan gudgeon populations from various water bodies. Minor differences were revealed in the number of lateral line scales and branched rays in the fins. Our data on breast squamation of the Turkestan gudgeon from the Yrgaity River do not correspond to the results of a previous study of the population from this river.