STUDIES ON DEROPRISTIS INFLATA (MOLIN), ITS LIFE HISTORY AND AFFINITIES TO TREMATODES OF THE FAMILY ACANTHOCOLPIDAE

Abstract

The cercaria of D. inflata is a trichocercous larva developing in simple rediae in the marine snail, Bittium alternatum. It encysts in Nereis virens and the eel, Anguilla rostrata, serves as the definitive host. Deropristis and Dihemistephanus sturionis are excluded from the family Acanthocolpidae which is redefined to include for the first time the genera Lepidauchen, Pleorchis and Pseudolepidapedon. It is proposed that the family Allocreadiidae be restricted to include only forms known or believed likely to have ophthalmoxiphidiocer-cariae with main excretory tubules not reaching the cephalic region of the body before receiving secondary tubules. The Allocreadiidae and Acanthocolpidae are regarded as separate but closely related families. Anallocreadium is reduced to synonymy with Homalometron and the subfamily Anallocreadiinae is renamed HOMALOMETRINAE. The Lepocreadiinae, Homalometrinae and a new subfamily DEROPRISTIINAE are regarded as a distinct family, the Lepocreadiidae. The family Gyliauchenidae is believed to be nearer the Lepocreadiidae than the Paramphistomoidea. Whether the Allocreadiidae, Acanthocolpidae, Opecoelidae, Lepocreadiidae and Gyliauchenidae constitute only one or more than one superfamily is not apparent from the fragmentary knowledge of life histories and embryology.