Pinning down a polymorphic parasite: New genetic and morphological descriptions of Eimeria macropodis from the Tammar wallaby (Macropus eugenii)

► We identified Eimeria macropodis from the Tammar wallaby in Australia. ► E. macropodis showed variation in size and shape, typical of a polymorphic species. ► We discovered two copies of the 18S SSU gene, complicating genetic characterization. ► Two genetic markers (18S & COI) were needed to resolve the identity of E. macropodis. ► Our study paves the way for accurate identification of Eimeria in marsupial hosts.