Hookeria acutifolia Hook. & Grev. is reported here as a new genus and species record for Thailand. A description, line drawing and photographs are provided, and its lectotype is designated here.

A taxonomic study of the genus Ephemeropsis K.I.Goebel in Thailand is presented, based on the herbarium specimens and field survey. Only one species is recognized in the country, namely E. tjibodensis K.I.Goebel. Detailed description, line drawings, and SEM photographs are provided.

A review of the genus Calyptrochaeta Desv. in Thailand is presented, based on herbarium specimens and field surveys. Two species are recognized, namely C. remotifolia (Müll. Hal.) Z. Iwats. et al. and C. spinosa (Nog.) Ninh. A key to species, descriptions, and illustrations for the species of Calyptrochaeta occurring in Thailand are provided. In addition, lectotype for the names Eriopus spinosus Nog. (= C. spinosa) are also designated in here.