Disentangling an Asian puzzle: Two new bathynellid (Crustacea,Syncarida, Parabathynellidae) genera from Vietnam

In this paper the 17 asiatic species of the family Parabathynellidae are reviewed from a taxonomic point of view using bibliographic data. Two new genera and two new species are described from caves in Vietnam. Paraeobathynella n. g. presents a unique combination of characters (antennule: seven segments; antenna: six segments; mandible: pars incisiva with five teeth and pars molaris with 10 teeth; maxillule: distal endite with seven claws; exopod of the thoracopods with three or more segments and epipods present in thoracopods 3–7; pleopods absent; endopod of the Th 8 male with two setae; seven spines on the sympod and two spines on the endopod of the uropod and the small minimum size of the adult body) and exclusive characters like the Th 8 female having two small spines and one long seta and the general size and aspect of the Th 8 male and its lobes. Sketinella n. g. presents a unique combination of characters (antennule: eight segments; antenna; six segments; mandible: pars incisiva with six teeth and pars molaris with eight teeth: maxillule: distal endite with seven claws; exopod of the thoracopods with three or more segments and epipods present in Th 3–7; endopod of the thoracopod 8 male with two setae; 12 spines on the sympod and two spines on the endopod and seven setae on the exopod of the uropod) and characters exclusive to the asiatic species are: a pair of pleopods reduced to a single seta; a very distinctive basipod and outer lobe of the Th 8 male and an exopod of the Th 8 male with a small tooth or protuberance. This is the first time that the Parabathynellidae has been found in Vietnam, this find extends the range of distribution of this family in Asia.