Research of specimens collected in South Vietnam by the staff of IEE RAS significantly increased our knowledge about cladocerans of Southeast Asia

Fig.1: P.G. Gharibyan sampling the Mekong Delta in 2023.

Based on the results of studying samples collected during an expedition to South Vietnam in 2023, as well as samples previously collected by various colleagues during work in Vietnam as part of the activities of the Joint Russian-Vietnamese Tropical Research and Technology Center, employees of the Laboratory of Ecology of Aquatic Communities and Invasions of the Institute of Ecology and Evolution of the Russian Academy of Sciences (co-authored with Vietnamese colleagues) published four articles in the journal "Zootaxa" devoted to the systematics and faunistics of cladoceran crustaceans in Vietnam and throughout Southeast Asia. Two species widespread in the paleotropics have been redescribed in accordance with modern standards of morphological work. A new species of the genus Ovalona (Van Damme & Dumont, 2008) is described, named after one of the active participants in these works, P.G. Gharibyan. This is just the beginning of work devoted to the cladoceran crustaceans of Vietnam. In 2024, a new expedition is planned to further northern regions of South Vietnam with the aim of further studying zooplankton.

Fig.2: *Ilyocryptus raridentatus* Smirnov, 1989 (Cladocera: Ilyocryptidae) is a relatively common benthic species found in the Far East of Asia and Australia.

Articles:

Garibian P.G., Kotov A.A., 2024. Study of rarely occurring males of Bosminopsis сf. africanus Daday, 1908 (Cladocera: Bosminidae) from SE Asia permits clarification of male-character based differentiation within the genus. Zootaxa 5446 (2): 295–300. https://doi.org/10.11646/ZOOTAXA.5446.2.12

Dadykin I.A., Định N., Shiel R.J., Kotov A.A., 2024. Redescription of Ilyocryptus raridentatus Smirnov, 1989 (Cladocera: Ilyocryptidae). Zootaxa Zootaxa 5468 (2): 331–349. https://doi.org/10.11646/ZOOTAXA.5468.2.5

Kotov A.A., Garibian P.G., Dadykin I.A., Gusakov V.A., Định C.N., Tiến N.V., Ji G., Shiel R.J., 2024. Species distribution ranges of Ilyocryptus Sars, 1862 (Cladocera: Ilyocryptidae) fit the transitional zone between Boreal and Tropical Provinces in the Far East. Zootaxa 5471 (2): 232–240. https://doi.org/10.11646/ZOOTAXA.5471.2.3

Sinev A.Y., Dadykin I.A., Dịnh C.N., 2024. A new species of the genus Ovalona Van Damme & Dumont, 2008 (Cladocera: Anomopoda: Chydoridae) from South-East Asia, related to Australian Ovalona archeri (Sars, 1888). Zootaxa 5448(2): 273-282. https://doi.org/10.11646/ZOOTAXA.5448.2.7