Hostname: page-component-848d4c4894-mwx4w Total loading time: 0 Render date: 2024-06-17T15:52:19.593Z Has data issue: false hasContentIssue false

The attachment of the monogenean Discocotyle sagittata Leuckart to the gills of Salmo trutta L.

Published online by Cambridge University Press:  06 April 2009

J. Llewellyn
Affiliation:
Department of Zoology and Comparative Physiology, University of Birmingham
I. L. Owen
Affiliation:
Department of Zoology, University College of Wales, Aberystwyth

Extract

The monogenetic trematode Discocotyle sagittata attaches itself to the gills of Salmo trutta with its long axis inclined to the long axis of the primary lamella to which it is attached, the direction of inclination being determined by the incidence of the gill-ventilating current of the host. The inclination is to some extent brought about by an asymmetrical disposition of the posterior adhesive organs, but Discocotyle appears to retain a primitive unspecialized character in that the asymmetrical disposition is facultative and not obligatory and permanent as in Axine.

The adhesive apparatus consists of four pairs of clamps and one pair of hooks. The hooks appear to be the persistent posterior hooks of the larva.

Each clamp is operated by an extrinsic muscle-tendon-fair-lead-hinged-jaws system generally similar but possibly less efficient than the corresponding system in Plectanocotyle gurnardi. Scheuring's and Sproston's interpretations of the clamp-closing mechanism of Discocotyle as a spring system are wrong.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1960

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Diesing, C. M. (1850). Systema Helminthum, 1, 679 pp. Vindobonae.Google Scholar
Hughes, G. M. & Shelton, G. (1958). The mechanism of gill ventilation in three freshwater teleosts. J. Exp. Biol. 35, 807–23.CrossRefGoogle Scholar
Leuckart, F. S. (1842). Helminthologische Beiträge. Zoologische Bruchstücke, 3, Freiburg.Google Scholar
Llewellyn, J. (1956 a). The adhesive mechanisms of monogenetic trematodes: the attachment of Plectanocotyle gurnardi (v. Ben. & Hesse) to the gills of Trigla. J. Mar. Biol. Ass. U.K. 35, 507–14.CrossRefGoogle Scholar
Llewellyn, J. (1956 b). The host specificity, micro-ecology, adhesive attitudes, and comparative morphology of some trematode gill parasites. J. Mar. Biol. Ass. U.K. 35, 113–27.Google Scholar
Llewellyn, J. (1957 a). The mechanism of the attachment of Kuhnia scombri (Kuhn, 1829) (Trematoda: Monogenea) to the gills of its host Scomber scombrus L., including a note on the taxonomy of the parasite. Parasitology, 47, 30–9.CrossRefGoogle Scholar
Llewellyn, J. (1957 b). Host specificity in monogenetic trematodes. First Symposium on Host Specificity among Parasites of Vertebrates, Neuchâtel, pp. 199212.Google Scholar
Llewellyn, J. (1957 c). The larvae of some monogenetic trematode parasites of Plymouth fishes. J. Mar. Biol. Ass. U.K. 36, 243–59.CrossRefGoogle Scholar
Llewellyn, J. (1958). The adhesive mechanisms of monogenetic trematodes: the attachment of species of the Diclidophoridae to the gills of gadoid fishes. J. Mar. Biol. Ass. U.K. 37, 6779.Google Scholar
Scheuring, L. (1938). Beiträge zur kenntnis von Discocotyle sagittatum, Dies. Grigore Antipa, Hommage á son oeuvre, Bucuresti, pp. 535–50.Google Scholar
Shaffer, E. (1916). Discocotyle salmonis nov.spec., ein neuer Trematode an den Kiemen der Regenbogenforelle (Salmo irideus). Zool. Anz. 46, 257–71.Google Scholar
Sproston, N. G. (1946). A synopsis of the monogenetic trematodes. Trans. Zool. Soc. Lond. 25, 185600.CrossRefGoogle Scholar