Lyperosomum intermedium is a parasitic trematode belonging to the subclass Digenea that infects the marsh rice rat (Oryzomys palustris). The species was first described in 1972 by Denton and Kinsella, who wrote that it was closest to Lyperosomum sinuosum, known from birds and raccoons in the United States and Brazil. Three years later, Denton and Kissinger placed the two, together with a number of other species, in a new subgenus of Lyperosomum, Sinuosoides. Species of Lyperosomum mainly infect birds; L. intermedium is one of the few species to infect a mammal.