THE MORPHOLOGY, LIFE-HISTORY, AND TAXONOMIC RELATIONS OF LEPOCREADIUM AREOLATUM (LINTON, 1900) STUNKARD, 1969 (TREMATODA: DIGENEA)

¹ The American Museum of Natural History, New York, New York and the Marine Biological Laboratory, Woods Hole, Massachusetts

Digenetic trematodes from the white perch, Morone americana, were identified by Linton (1900) as Distomum areolatum Rudolphi, 1809. He (1901) referred specimens from the cunner, Tautogolabrus adspersus, and the winter flounder, Pseudopleuronectes americanus, to the same species. These worms were collected at Woods Hole, Massachusetts. Other specimens were taken from Bairdiella chrysura, Micropogon undulatus, Orthopristis chrysopterus, and Sciaaenops ocellatus at Beaufort, North Carolina. Linton (1940) included all these worms in a new species, Lepocreadium trullaforme. But they are not specifically identical with L. trullaforme and their taxonomic status has been uncertain. The metacercariae of these worms have been known for many years an unencysted distomes in the ctenophores and medusae taken in plankton collections. The discovery of an ophthalmotrichocercous cercaria from Nassarius trivittatus with the same morphology, has led to the completion of the life-cycle and the resolution of the taxonomic status of the species, which proved to be Lepocreadium areolatum (Linton, 1900) Stunkard, 1969. Cercariae from N. trivittatus penetrated and matured in medusae of Podocoryne carnea, maintained in the laboratory. Experimentally infected medusae were fed twice a week to cunners, which had been isolated for more than a month, and a series of developmental stages from juveniles to gravid worms were recovered. All stages in the life-cycle are described and figured.