Protomonascus nybelini gen. et sp. n. (Trematoda: Fellodistomidae) from Elops senegalensis Regan, 1909, on the west coast of Africa.

The worms were taken from openings of the pyloric ceca of Elops senegalensis collected on the Gambian coast. Protomonascus is characterized by an oral sucker with a longitudinal opening, a coiled seminal vesicle, a long pars prostatica, diagonal testes, and a trilobed ovary. The genus resembles Monascus, from which it differs primarily in having 2 intestinal ceca ending blindly, the pyriform cirrus sac with coiled seminal vesicle, and the long pars prostatica. The new genus is placed in the subfamily Monascinae within the family Fellodistomidae. During January 1972, Professor Orvar Nybelin examined five specimens of the teleost, Elops senegalensis Regan, 1909, from the fish market in Bathurst, Gambia. At the openings of the pyloric ceca in three of the fishes, he found one, three, and seven specimens of a digenean, which he presented to the writer for examination. The worms had been fixed in 4% formaldehyde solution and stored in 70% alcohol. Four whole mounts were stained with Mayer's carmalum and two specimens were sectioned and stained with Heidenhain's azan. Figures were drawn with the aid of a camera lucida and measurements are in microns unless otherwise specified. Protomonascus gen. n.