The first stygobitic species of atyid freshwater shrimps from Vietnam is described from Cuc Phuong National Park, Northern Vietnam. Caridina thachlam sp. nov. can be distinguished from its congeners by a suite of morphological characters such as strongly reduced eyes without eyestalk, short and almost unarmed rostrum and slender pereiopods. Molecular phylogenetic data from the mitochondrial cytochrome oxidase subunit I (COI) and 16S ribosomal RNA genes also support the distinctiveness of the new species from all other species that we have examined.

The genus Leptophion is recorded for the first time from Vietnam, including new records of three species, viz. L. giganteus Shimizu & Watanabe, L. maculipennis (Cameron) and L. radiatus (Uchida), for the country. The comparative morphological and pictorial characters of Vietnamese specimens were given. In addition, variations and in-country distribution of newly recorded species were also provided.