A new species of microgastropod, Orbitestella amphaengensis, is described from Holocene Bangkok clay, where a whale’s skeleton (3,380 ± 30 years old) was found, in Samut Sakorn Province, Central Thailand. This new orbitestellid species is characterised by the presence of prominent keels, characteristics of nodules, spiral series, and numerous axial ribs. The new species is the oldest microgastropod of this family hitherto reported in Thailand and is also the first record of the genus Orbitestella. The presence of this marine microgastropod indicates that the depositional environment was shallow marine deposits.

A new species of the terrestrial haemadipsid genus Tritetrabdella, Tritetrabdella longiducta, from northern Indochina is described. The new species is distinguished from all congeners by the combination of triannulate somite VII, uniannulate somite XXV, three lobes of respiratory auricles in somites XXV–XXVII, 57 friction rays on caudal sucker, male gonopore (in somite XI b5/b6) and female gonopore (in somite XII b5) positions and slightly folded vaginal sac. Phylogenetic analyses using nuclear 18S rRNA and 28S rRNA, in addition to mitochondrial cytochrome c oxidase subunit I markers, confirmed that the new species forms a unique lineage among the known congeners. A key to all the species of Tritetrabdella is provided.

A new species of the coral-associated palaemonid shrimp, Philarius venustus, is described and illustrated based on a single male specimen collected from Sanya, Hainan Island, China. The new species could be distinguished from the congeneric species by a series of morphological features and the unique colour pattern. The COI barcode was obtained from the material and submitted to GenBank