Species diversity of rotifers (Rotifera: Eurotatoria) of Phu Ninh Lake with five new records from Vietnam

A total of sixty-one taxa of rotifer, belonging to 15 families, 3 orders were identified from the Phu Ninh Lake, Vietnam. Of these, five species were recorded new to Vietnam Rotifera fauna, including Lecane acanthinula (Hauer, 1938), L. sola (Hauer, 1936), L. thailandensis Segers & Sanoamuang, 1994, L. pyriformis (Daday, 1905), and Mytilina bisulcata (Lucks, 1912). The result raised the total number of rotifers known from Vietnam to 227 species. Moreover, the results showed that the number of species recorded increased with the increase of sample size, which followed the equation y=12.85+14.12log(x) (R2 = 0.99). Based on the estimators, the α-diversity of rotifers in Phu Ninh Lake might be up to 67±4 taxa (according to the Bootstrap index), 71±8 taxa (according to the Chao index), or even up to 79 taxa (according to Jacknife 2 index).