STUDIES ON THE TREMATODE FAMILY MICROPHALLIDAE TRAVASSOS, 1921

Abstract

Adult worms inhabit the intestine of shore birds (plovers, sandpipers, etc.); cercariae develop in oval sporocysts in the mud snail, Nassa obsoleta, escape into moist sand, penetrate the branchial lamellae of the beach flea, Talorchestia longicornis, and then migrate to the pericardial cavity where they develop into metacercariae. Young, herring gulls (Larus argentatus) were used as exptl. definitive hosts. The ecology of the hosts and parasites indicates a very close relation between the habits of the animals involved. The genus Gynaecotyla is emended and the valid spp. indicated. The uterus lying wholly posterior to or overlapping the testes; the well-developed acetabula, not enclosed with the genital suckers; the genital pore not closely associated with the acetabulum; the 2[(2 + 2) + (2 + 2)] excretory system; and the use of crustaceans for 2d intermediate hosts are characters separating the Microphallidae from the Heterophyidae. The presence of a seminal receptacle and Laurer''s canal in members of the Microphallidae is emphasized.