Biodiversity of Tintinnids (Tintinnida) in Khanh Hoa- Binh Thuan waters.

Abstract

Tintinnids are an important protozoan group in the aquatic food web and had been widely studied in various waters. There are about 1000 known species in the world. However, there have been very few taxonomic studies in Viet Nam and therefore the number of Tintinnid taxa and their distribution are poorly known. The present study documents 65 tintinnids species belonging to 30 genera and 13 families in samples collected from Khanh Hoa - Binh Thuan waters in 2016 and 2017. There were 17 new taxa records for Viet Nam protozoan fauna, raising the number of tintinnids recorded in Viet Nam to 125 taxa. Tintinnid assemblages in Khanh Hoa-Binh Thuan waters shared about 17 species with Ha Long Bay, 32 species with Con Co island and 26 species with coastal waters of South Viet Nam. Analysis of species diversity shows that the Shannon diversity index H' varied from 1.5 to 2.6. Distribution of species numbers and diversity in the Khanh Hoa - Binh Thuan waters revealed possible combined effects of hydrographical activities (e.g. upwelling), Mekong river influent (e.g. salinity), and food available on tintinnid communities.