Eimeria kinsellai is an apicomplexan parasite of the genus Eimeria that infects the marsh rice rat. It was discovered in 1970 at Paynes Prairie, Alachua County, Florida. A different Eimeria, Eimeria palustris, has been found in Alabama marsh rice rats. E. kinsellai differs from other Eimeria found in rice rats, such as Eimeria couesii, Eimeria oryzomysi, Eimeria ojastii, and E. palustris, in anatomical details. It was named after parasitologist John M. Kinsella.
Notocotylus fosteri is a parasitic fluke that infects the marsh rice rat in Florida.
Aonchotheca forresteri is a parasitic nematode that infects the marsh rice rat in Florida. Occurring mainly in adults, it inhabits the stomach. It is much more common during the wet season, perhaps because its unknown intermediate host is an earthworm that only emerges when it rains. The worm was discovered in 1970 and formally described in 1987. Originally classified in the genus Capillaria, it was reclassified in Aonchotheca in 1999. A. forresteri is small and narrow-bodied, with a length of 13.8 to 19.4 mm in females and 6.8 to 9.2 mm in males. Similar species such as A. putorii differ in features of the alae and spicule, the size of the female, and the texture of the eggs.
Ascocotyle angrense is a fluke in the genus Ascocotyle that mainly infects birds. It has previously been confused with A. diminuta, which infects fish-eating birds and raccoons. It has also been recorded from the marsh rice rat in a saltwater marsh at Cedar Key, Florida, where it occurred in 25% of animals.
Ascocotyle pindoramensis is a fluke in the genus Ascocotyle that occurs along the eastern coast of the Americas from Brazil to Nicaragua, Mexico, Louisiana, and Florida and doubtfully in Egypt. It occurs in the intestine of its definitive hosts. Hosts recorded in the wild include the least bittern, roseate spoonbill, great blue heron, striated heron, stripe-backed bittern, yellow-crowned night heron, black-crowned night heron, osprey, Neotropic cormorant, and marsh rice rat. In the marsh rice rat, it infected 9% of rats examined in a 1970–1972 study in the salt marsh at Cedar Key, Florida, but none in a freshwater marsh. A. pindoramensis has been experimentally introduced into the domestic duck, chicken, dog, house mouse, and golden hamster. It occurs in various body parts of its intermediate hosts—the poeciliid fish Phalloptychus januarius, Poecilia catemaconis, Poecilia mexicana, Poecilia mollienisicola, Poecilia vivipara, and a species of Xiphophorus and the cichlid Tilapia. It was first described as Pygidiopsis pindoramensis in 1928 and subsequently as Pseudoascocotyle mollienisicola in 1960. The latter species was moved to Ascocotyle in 1963, but only in 2006 it was recognized that the two represent the same species, which is now known as Ascocotyle pindoramensis. Other flukes from Argentina and Mexico that were identified as Pygidiopsis pindoramensis instead represent a different species of Pygidiopsis.
Echinochasmus schwartzi is a fluke that infects dogs, muskrats, and marsh rice rats. It uses Fundulus fish as its intermediate host. Adults are similar to Echinochasmus microcaudatus, but differ in features of the oral sucker.
Fibricola lucida is a fluke that infects Virginia opossums, American minks, and marsh rice rats in North America. In a study in Florida, F. lucida was the only fluke of the marsh rice rat that occurred in both the freshwater marsh at Paynes Prairie and the saltwater marsh at Cedar Key. At the former locality, it infected 11% of rice rats and the number of worms per infected rat ranged from 1 to 65, averaging 17. At Cedar Key, 67% of rice rats were infected and the number of worms per infected rat ranged from 1 to 1975, averaging 143.
Gynaecotyla adunca is a fluke that normally infects birds. It has also been found in 15% of a sample of the marsh rice rat from a salt marsh at Cedar Key, Florida. It uses fiddler crabs such as Uca rapax as its intermediate host.
Maritrema prosthometra is a parasitic fluke from North America. It was first described in 1969 from the intestine of the clapper rail in eastern North America. Later, it was also found in the small intestine of 5% of a sample of marsh rice rats collected in a salt marsh at Cedar Key, Florida, where it used the fiddler crab Uca pugilator as an intermediate host.
Maritrema is a genus of trematodes (flukes) in the family Microphallidae, although some have suggested its placement in the separate family Maritrematidae. It was first described by Nikoll in 1907 from birds in Britain. Species of the genus usually infect birds, but several have switched hosts and are found in mammals, such as the marsh rice rat. Several species use the fiddler crab Uca pugilator as an intermediate host.
Microphallus basodactylophallus is a species of digenean parasite in the genus Microphallus. It was first described in 1969, as Carneophallus basodactylophallus, from southern Louisiana, where the raccoon is the definitive host, the first intermediate host is the snail Lyrodes parvula, and the second intermediate host is the crab Callinectes sapidus. It was later moved to the genus Microphallus. In 1988, John Kinsella recorded it from the marsh rice rat in a saltmarsh at Cedar Key, Florida. There, it was one of the most prevalent parasites in the marsh rice rat and used C. sapidus as an intermediate host.
Odhneria odhneri is a digenean parasite in the genus Odhneria of family Microphallidae. It infects several species of shorebirds, including the willet, as well as the marsh rice rat.
Acanthotrema cursitans is a species of fluke in the genus Acanthotrema. It infects the marsh rice rat Oryzomys palustris, the raccoon Procyon lotor, the Virginia opossum Didelphis virginiana, the snail Cerithidea scalariformis, and killifishes of the genus Fundulus on the Gulf Coast of Florida. It was first described as Cercaria cursitans in 1961, then moved to Stictodora in 1974, and to Acanthotrema in 2003.
Urotrema scabridum is a fluke in the genus Urotrema of family Urotrematidae. Recorded hosts include:
Litomosoides scotti is a parasitic nematode in the genus Litomosoides. First described in 1973, it infects the marsh rice rat and is known from a saltwater marsh at Cedar Key, Florida.
Parastrongylus schmidti is a species of parasitic nematode in the genus Parastrongylus. It was first described as Angiostrongylus schmidti in 1971 from the marsh rice rat in Florida, but later assigned to Parastrongylus.
Spiruridae is family of nematodes in the order Spirurida. An unidentified parasitic larval member of this family has been recorded in the marsh rice rat in a salt marsh at Cedar Key, Florida, and also in fiddler crabs (Uca) there; it is perhaps a bird parasite that does not reach maturity in the rice rat.
Trichostrongylus affinis is a species of parasitic nematode in the genus Trichostrongylus. It primarily infects cottontails (Sylvilagus), but has also been found in the hispid cotton rat and the marsh rice rat.
Trichostrongylus sigmodontis is a species of parasitic nematode in the genus Trichostrongylus. It primarily infects the hispid cotton rat, but has also been found in the marsh rice rat.
