''Chromidina'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

apostome The Apostomatida are an order of ciliates from the class Oligohymenophorea. Individual organisms from this order are called apostomes. They are symbiotic with Crustacea. For majority of their life cycle they are dormant and encysted on their ho ...

ciliate The ciliates are a group of alveolates characterized by the presence of hair-like organelles called cilia, which are identical in structure to flagellum, eukaryotic flagella, but are in general shorter and present in much larger numbers, with a ...

s of the family Opalinopsidae. Species of ''Chromidina'' are parasitic in the renal and pancreatic appendages of

cephalopods A cephalopod is any member of the molluscan Taxonomic rank, class Cephalopoda (Greek language, Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral symm ...

. In 2016, a molecular study found that the closest relatives of ''Chromidina'' spp. were species of the apostome '' Pseudocollinia''.

References

Oligohymenophorea Ciliate genera Taxa described in 1905 {{ciliate-stub