Tags: Crustacean.
Catomerus is a monotypic genus of intertidal/shallow water acorn barnacle that is found in warm temperate waters of Australia. The genus and species is very easily identified by whorls of small plates surrounding the base of the primary shell wall; no other shoreline barnacle species in the Southern Hemisphere has that feature. This species is considered to be a relic as these plates are found only in primitive living lineages of acorn barnacles or in older fossil species.