Monorchiidae (Trematoda) from Fishes of Apalachee Bay, Gulf of Mexico

Abstract

Five species of monorchiid trematodes, including two new ones, Diplomonorchis floridensis from Symphurus plagiusa (L.) and Pseudohurleytrema shorti from Selene vomer (L.), are reported. The status of hurleytrematine genera with a single testis is discussed. Parahurleytrema, a new genus characterized by a bipartite seminal vesicle and terminal organ, is created for P. trachinoti (Thomas, 1959) n. comb. (syn. Hurleytrema trachinoti Thomas) and P. coronatumr (Manter and Pritchard, 1961) n. comb. (syn. Hurleytrema coronatum Manter and Pritchard). The genus, Pseudohurleytrema Manter, 1942, characterized by a single seminal vesicle and bipartite terminal organ, includes P. eucinostomi Manter, 1942, P. shorti (this paper), and P. malabonensis (Velasquez, 1961) n. comb. (syn. Hurleytrema malabonensis Velasquez). The similarity of monorchiid fauna of Beaufort, North Carolina and northern Gulf of Mexico is discussed. More than 50 species of trematodes were collected from marine fishes of Apalachee Bay over a period of 10 weeks during summers of 1963 and 1964. Five of species, all belonging to family Monorchiidae, are discussed in this paper; others are subject of another paper (Nahhas and Short, in press) to be published elsewhere. Manter (1942) reported nine species of monorchiids from Tortugas, Florida. In contrast, only three species are recorded from northern half of Gulf: Genolopa sp. was reported from Louisiana coast (Sparks, 1958); Diplomonorchis leiostomi Hopkins, 1941 is known from Tampa Bay (Sogandares-Bernal and Hutton, 1959a) and coasts of Louisiana and Texas (Sparks, 1958, 1960); and Lasiotocus minutum (Manter, 1931) from Tampa Bay (Sogandares-Bernal and Hutton, 1959b). The last two species first described from Beaufort, North Carolina, have not been reported from southern part of Gulf of Mexico or Caribbean. In discussing certain aspects of zoogeography of digenetic trematodes of shallow-water fishes in Gulf of Mexico, Sparks (1960) concluded that the northern Gulf population is more closely related to population of Atlantic coast of North America than to that of Tortugas. This conReceived for publication 3 August 1964. 16 clusion is well substantiated by members of family Monorchiidae, and species reported here confirm its validity, at least as far as this family is concerned.