Microrchis oligovitellinum Lunaschi, 1987

Material deposited: MACN-Pa 596, 597 (new voucher material), MLP (type material).

Hosts: Luciopimelodus pati and Trachelyopterus striatulus [= Trachycoristes striatulus (Steindachner)] (type host not assigned), Ageneiosus inermis *, A. militaris *, Pterodoras granulosus *.

Localities: Atalaya (Magdalena) and Punta Lara (Ensenada), Buenos Aires Province (type locality not assigned); Colastiné River** (tributary of Paraná River), Santa Fe Province.

Site of infection: Anterior, middle and posterior part of intestine.

References: Lunaschi (1987), Arredondo (2013).

Remarks: New hosts and locality records.