General aspects of the large branchiopod crustacean fauna of Mongolia

 The Gobi Steppe of Mongolia supports numerous temporary water bodies of various sizes. No accurate information is available on the factors that shape the structure of their fauna, partly because they have been regarded as less important environments than permanent lakes. This study represents the first comprehensive survey of the Recent large branchiopod fauna of Mongolia, which consists of at least 16 species. This faunal composition may have resulted from colonization through diversification in East Asia during the Cretaceous period of the Mesozoic era (ca. 135–65 My ago), and to some extent from immigration from Europe into Asia during the Cenozoic era. The distribution patterns of some geologically ancient taxa most probably reflect the ancient hydrosphere. Five new records from Mongolia are presented: three species of Anos-traca, Branchinectella media (Schmankewitsch, 1873), Chirocephalus mongolianus Uéno, 1940, and Chirocephalus sp. (undescribed); one Spinicaudata, Cyzicus sp. (undescribed); and one Laevicaudata, Lynceus sp. (undescribed). The three undescribed species are localized-endemic to the Gobi Steppe. The purpose of this paper is to draw attention to some of the scientific interest and value of ephemeral aquatic habitats in Mongolia, and to argue that hydrobiologists, water resource managers, and conservationists need to take greater interest in temporary habitats.