Family Desmodoridae Filipjev, 1922

101. Prodesmodora circulata (Micoletzky, 1913) Micoletzky, 1925 — {62} (0, 0, 0, 9; 1)

Population structure and abundance. Three females (~ 1x10 3/m2).

Ecology and distribution. Hydrobiont. Widespread species. Found in the water bodies of many countries of Europe, Asia and in some areas of North and South America (Andrássy 2005; Decraemer & Smol 2006). Previously collected in one of the rivers of northern Vietnam (Gagarin & Nguyen 2008a).

102. Prodesmodora Micoletzky, 1923 sp.— {27, 31} (0, 7, 0, 0; 3)

Population structure and abundance. Three juvenile specimens at the first and four females at the second site (more than 1x10 3/m2).

Remarks. These specimens are smaller (length of adult females is less than 500 µm) and have some other differences from P. circulata from the locality noted above. Most likely they belong to another, as yet undescribed, species, but we are not absolutely sure about that. Besides P. circulata, no other species of the genus have been reported from Vietnam.