The new crab is currently only known from the Line and Society Islands in the Central Pacific. It lives among dead Pocillipora skeletons (AKA live rock) and Halimeda macroalgae where it spends its days filter-feeding plankton and detritus with its specialized, feathery forearms (maxillipeds).
Porcelain crabs are common reef citizens and are reef-safe. Their large, intimidating pinchers are used primarily for defense; the bulk of its diet is from filter-feeding supplemented by occasional scavenging. These peaceful crabs remain small in size, rarely exceeding 2 inches in length.
While some fish have been collected from the Central Pacific (e.g. Pseudanthias aurulentus). it’s unlikely invertebrates, especially tiny crabs, will make their way into the aquarium trade any time soon.
Petrolisthes paulayi is described in ZooKeys.