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The biology of Leptocotyle minor, a skin parasite of the dogfish, Scyliorhinus canicula*

Published online by Cambridge University Press:  06 April 2009

G. C. Kearn
Affiliation:
School of Biological Sciences, University of East Anglia, Norwich

Extract

Leptocotyle minor is a monogenean parasite specialized for living on the denticlecovered skin of the dogfish Scyliorhinus canicula. Each adult parasite attaches itself to the outer surface of a single denticle. Small postlarvae are found on the inner surfaces of the denticles. The denticles have hard enamel on both inner and outer exposed surfaces. Haptoral hooks, such as are present in other monogenean oncomiracidia, would be unable to penetrate this hard surface and are absent in postlarval and adult parasites which attach themselves by cement. The oncomiracidium possesses six haptoral spicules which may be homologues of the marginal hooks of other monogeneans, but these spicules disappear early in postoncomiracidial development.

Adult parasites feed on the host's epidermis which lies between the denticles. The position of small postlarvae on the inner surfaces of the denticles enables them to reach the epidermis for feeding purposes. Growth then permits young parasites to migrate away from the epidermis on to the outer surfaces of the denticles.

Adult parasites move from one denticle to another in a leech-like manner, and copulation occurs between parasites which meet as a result of these movements.

I am grateful to the Director and Staff of the Plymouth Laboratory for their hospitality and particularly to Mr J. E. Green for his interest and co-operation.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1965

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References

Bychowsky, B. E. (1957). Monogenetic Trematodes, their Classification and Phylogeny, 509 pp. Moscow, Leningrad: Academy of Sciences, U.S.S.R. (English translation edited by W. J. Hargis, 1961. Washington: American Institute of Biological Sciences.)Google Scholar
Johnstone, J. (1911). Internal parasites and diseased conditions of fishes. Proc. Trans. Lpool. biol. Soc. 25, 88107.Google Scholar
Kearn, G. C. (1963 a). Feeding in some monogenean skin parasites: Entobdella soleae on Solea solea and Acanthocotyle sp. on Raia clavata. J. mar. biol. Ass. U.K. 43, 749–66.CrossRefGoogle Scholar
Kearn, G. C. (1963 b). The egg, oncomiracidium and larval development of Entobdella soleae, a monogenean skin parasite of the common sole. Parasitology, 53, 435–47.CrossRefGoogle Scholar
Kearn, G. C. (1963 c). The oncomiracidium of Capsala martinieri, a monogenean parasite of the sun fish (Mola mola). Parasitology, 53, 449–53.CrossRefGoogle Scholar
Kearn, G. C. (1964). The attachment of the monogenean Entobdella soleae to the skin of the common sole. Parasitology, 54, 327–35.CrossRefGoogle Scholar
Llewellyn, J. (1963). Larvae and larval development of monogeneans. Advanc. Parasit. 1, 287326.CrossRefGoogle ScholarPubMed
Llewellyn, J. & Euzet, L. (1964). Spermatophores in the monogenean Entobdella diadema Monticelli from the skin of sting rays, with a note on the taxonomy of the parasite. Parasitology, 54, 337–44.CrossRefGoogle Scholar
Paling, J. E. (1965). The functional morphology of the genitalia of the spermatophore-producing monogenean parasite Diplectanum aequans (Wagener) Diesing, with a note on the copulation of the parasite. Parasitology, (In the Press.)Google Scholar
Plymouth Marine Fauna (1958).Google Scholar
Sproston, N. G. (1946). A synopsis of the monogenetic trematodes. Trans. zool. Soc. Lond. 25, 185600.CrossRefGoogle Scholar