A collection of littoral caprellids from Phuket, Thailand has been studied. The material contained five
species: Metaproto novaehollandiae (Haswell, 1880), Protogeton incertus Mayer, 1903, Aciconula
sp., Metaprotella sandalensis Mayer, 1898, and Monoliropus hapipandi new species, which is
described in the present paper. Monoliropus hapipandi can be distinguished from the remaining species
of Monoliropus by the abdominal appendages reduced to a seta, the mandibular palp bi-articulate
instead of tri-articulate, and by the presence of a striking bi-toothed projection on the penultimate article
of the maxilliped palp. Monoliropus agilis, the closest species to M. hapipandi, is illustrated in detail
based on the type material, for comparison of both species. Lateral view figures for all species are given
and a key to the Caprellidea from Phuket is also provide
