perkinsus perkinsus perkinsus is a genus of alveolates in the phylum perkinsozoa. the genus was erected in 1978 to better treat its type species, perkinsus marinus, known formerly as dermocystidium marinum. these are parasitic protozoans that infect molluscs, at least some of which cause disease and mass mortality. p. marinus is the most notorious, causing the disease perkinsosis, or dermo, in wild and farmed oysters. perkinsus scientific classification domain: eukaryota clade: diaphoretickes clade: sar clade: alveolata phylum: perkinsozoa class: perkinsea order: perkinsida family: perkinsidae genus: perkinsuslevine, 1978 as of 2004, six valid species were in the genus. at least two more have been described since then. species and common hosts include: perkinsus andrewsi on baltic clam (macoma balthica) perkinsus beihaiensis on the oysters magallana hongkongensis and m. ariakensis perkinsus chesapeaki on soft-shell clam (mya arenaria) perkinsus honshuensis on manila clam (venerupis philippinarum) perkinsus marinus on eastern oyster (crassostrea virginica) perkinsus mediterraneus on european flat oyster (ostrea edulis) perkinsus olseni (syn. p. atlanticus) on blacklip abalone (haliotis rubra) and grooved carpet shell (ruditapes decussatus) perkinsus qugwadii on yesso scallop (patinopecten yessoensis) p. andrewsi and p. chesapeaki might be the same species; because the latter was described first, the name p. andrewsi will be a synonym.