OBSERVATIONS ON TUBULOVESICULA PINGUIS (LINTON, 1910) MANTER, 1947 AND ON SYSTEMATICS OF THE HEMIUROID TREMATODES

¹ American Museum of Natural History, Central Park West at 79th Street, New York, New York 10024

Dinurus pinguis Linton, 1940 was described from a large collection of small trematodes, assembled during the previous forty years. Many of them had been assigned to other, different, species in earlier publications. There was no type-specimen but the account was based primarily on material from Menidia menidia. The specific diagnosis was indefinite, imprecise, and so general that it might include members of more than one genus. Dinurus pinguis was transferred by Manter (1947) to the genus Tubulovesicula Yamaguti, 1934. The species, as restricted, is common in Menidia menida at Woods Hole, Massachusetts and is redescribed from juvenile and adult specimens.

Sinclair, Smith and Sullivan (1972) suppressed Stomachicola magnus (Manter, 1931) Manter, 1947 as a synonym of Stomachicola rubeus (Linton, 1910) Manter, 1947 and predicated that Tubulovesicula pinguis is merely a stage in the life-cycle of S. rubeus. The identity of S. rubeus and S. magnus may be accepted, but the proposal that T. pinguis may develop into S. rubeus is rejected.

The collection, organization and integration of information on the genetic relations and systematics of the hemiurid trematodes discloses different interpretations and evaluations of taxonomic features. The present status is reviewed. The divergence of opinion results in large measure from lack of knowledge of life-cycles and developmental stages of marine species. Information from freshwater species, although limited, is significant and helpful. Homologous features, common to all hemiurid species, include the nature of the eggs, the peculiar bristle-bearing miracidia, the presence of rediae in the life-cycle, the characteristic cystophorous cercariae that are eaten by small crustaceans, and the unencysted metacercariae in various planktonic invertebrates. These striking features, shared by all members, portray a common genetic constitution and support the postulate of Odhner (1905), Fuhrmann (1928) and others that the Azygiidae, Hemiuridae and Didymozoidae are members of a common superfamily.