Abstract
The pontoniine shrimp Philarius gerlachei (Nobili, 1905) is revised based on Nobili's type material from the Persian Gulf and specimens recently collected in Madagascar, Australia and French Polynesia. Philarius gerlachei is redescribed and four species are described as new: P. polynesicus n. sp. from Moorea, French Polynesia; P. rufus n. sp. and P. minor n. sp., both from Heron Island, Great Barrier Reef, Australia, and P albimaculatus n. sp. from Nosy-Be, Madagascar. These species differ from P. gerlachei and/or from each other by a combination of morphological characters and species-diagnostic colour patterns. All species of Philarius appear to be obligate associates of branching corals of the genus Acropora.
NSTL