Testate Amoebae from South Vietnam Waterbodies with the Description of New Species Difflugia vietnamica sp. nov.

摘要

Testate amoebae in Vietnam are still poorly investigated. We studied species composition oftestate amoebae in 47 waterbodies of South Vietnam provinces including natural lakes,reservoirs, wetlands, rivers, and irrigation channels. A total of 109 species and subspeciesbelonging to 16 genera, 9 families were identiedfrom 191 samples. Thirty-vespecies andsubspecies were observed in Vietnam for the rsttime. New species Diugiavietnamica sp.nov. is described. The most species-rich genera are Diugia(46 taxa), Arcella (25) andCentropyxis (14). Centropyxis aculeata was the most common species (observed in 68.1%samples). Centropyxis aerophila sphagniсola, Arcella discoides, Diugiaschurmanni andLesquereusia modesta were characterised by a frequency of occurrence 20%. Other specieswere rarer. The species accumulation curve based on the entire dataset of this work wasunsaturated and well ttedby equation S = 19.46N0.33. Species richness per sample in naturallakes and wetlands were signicantlyhigher than that of rivers (p 0.001). The result of theSpearman rank test shows weak or statistically insignicantrelationships between speciesrichness and water temperature, pH, dissolved oxygen, and electrical conductivity.