9. * Prismatolaimus dolichurus de Man, 1880 — {3, 29, 53, 55, 69} (5, 7, 8, 9; 7)
Population structure and abundance. 1 to 2 juvenile specimens and/or females at each site. Ecology and distribution. Amphibiont. Inhabits very variable terrestrial and aquatic biotopes. Cosmopolitan. Occurs on all continents except for Antarctica (Zullini 2006; Andrássy 2007). Not recorded in Vietnam until the beginning of our studies on meiobenthos (Gusakov et al. 2014).
10. Prismatolaimus intermedius (Bütschli, 1873) de Man, 1880 — {27, 50, 51, 53–55, 59, 63, 65, 68} (0, 18,15, 27; 14)
Population structure and abundance. At site 50—five females (~ 2x10 3/m2), at the other sites—1 to 3 females (up to 1x10 3/m2).
Ecology and distribution. The ecology and distribution of P. intermedius are similar to the previous species except for the fact that in addition to Antarctica it has not been recorded in Australia (Zullini 2006; Andrássy 2007). This species was recovered from river bottom sediments and in soil biotopes of northern Vietnam (Nguyen & Nguyen 2005; Nguyen 2007).
11. Prismatolaimus de Man, 1880 spp. — {53, 57, 66, 69} (0, 4, 8, 18; 6)
Population structure and abundance. Just one juvenile specimen or female at each site. Remarks. This taxon includes individuals of species unidentified owing to various reasons.