Abstract

The results of a study on the qualitative and quantitative composition of modern planktonic Crustaceans (Cladocera, Diaptomidae, and Cyclopidae) of Lake Dood Tsagaan (northwestern Mongolia) are presented. A comparative analysis of the species composition of crustaceans according to new data and data obtained in the last century (1962–1963) has revealed an increase in the list of crustaceans by five Cladocera species and three Copepoda species, two of which belong to the order Cyclopoida and one to the order Calanoida. Ultrastructural studies of the main morphological parts of the copepod crustaceans Mixodiaptomus incrassatus (Sars, 1903), Acanthodiaptomus paulseni (Sars, 1903), and Cyclops glacialis Flossner, 2001 have been carried out for the first time using a scanning electron microscope (SEM). A detailed study of morphometric and morphological characters, including the use of a SEM, shows that C. glacialis from Lake Dood Tsagaan is identical to the species described in Turgen Kharkhiraa Uvs aimag and Nogoon nuur lakes in the northwest of Mongolia. Nowadays, the biomass of M. incrassatus, an important food object for the whitefish and other fish species, reaches 1100 mg/m³.

中文翻译：

---

杜德察干湖（蒙古达尔哈德盆地）现代枝角类和桡足类甲壳类动物群（甲壳类：枝角类、桡足类）

摘要

介绍了杜德察干湖（蒙古西北部）现代浮游甲壳类（枝角类、甲壳类和巨蜥科）定性和定量组成的研究结果。根据新数据和上个世纪（1962-1963）获得的数据对甲壳类动物的物种组成进行比较分析，发现甲壳类动物名单增加了五种枝角类和三种桡足类物种，其中两种属于甲壳目巨蚓目（Cyclopoida）和卡拉诺亚目（Calanoida）中的一种。首次使用扫描电子显微镜 (SEM) 对桡足类甲壳类Mixodiaptomus incrassatus (Sars, 1903)、Acanthodiaptomus paulseni (Sars, 1903) 和Cyclops glacialis Flossner, 2001主要形态部分进行了超微结构研究。对形态测量和形态特征的详细研究（包括使用 SEM）表明，来自 Dood Tsagaan 湖的C. glacialis与蒙古西北部 Turgen Kharkhiraa Uvs AImag 和 Nogoon nuur 湖中描述的物种相同。如今，白鲑和其他鱼类的重要食物对象M. incrassatus的生物量已达到1100 mg/m ³。