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Morphological adaptations of Aglaophenia harpago (Hydrozoa: Plumulariidae) to enhance feeding efficiency

Published online by Cambridge University Press:  11 May 2009

R. G. Hughes  and
D. H. J. Henderson
R. G. Hughes
Affiliation:
Centre for Research in Aquatic Biology, School of Biological Sciences, Queen Mary College, University of London, London, El 4NS
D. H. J. Henderson
Affiliation:
Centre for Research in Aquatic Biology, School of Biological Sciences, Queen Mary College, University of London, London, El 4NS
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Extract

The pinnate (feather-shaped) hydrocauli (stems) of Aglaophenia harpago are dish-shaped with the food catching hydranths borne on the convex side of the lateral branches, a morphology recognised as an adaptation to feeding from unidirectional currents. A. harpago experience unidirectional currents because the hydrocauli are able to rotate close to their bases on an articulation in the perisarc (the tubular exoskeleton) so that the concave surface always faces into the current and the hydranths face leeward. The structure of this articulation, revealed by light and electron microscopy, is described and its mechanism interpreted. The articulation consists of two oblique grooves of thin flexible perisarc which traverse around the hydrocaulus at an angle of 62–65°. The grooves terminate in areas of perisarc divided into longitudinal lamellae (probably of structural protein). The grooves and lamellae confer the flexibility which allows the hydrocaulus to ‘fold’ up to 90° clockwise or anticlockwise across each groove. The lamellae maintain the longitudinal support necessary to prevent the hydrocaulus collapsing.

Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 69 , Issue 1 , February 1989 , pp. 17 - 25
Copyright
Copyright © Marine Biological Association of the United Kingdom 1989

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References

REFERENCES

Boero, F., 1981. Systematics and ecology of the hydroid population of two Posidonia oceanica Meadows. Marine Ecology, Naples, 2, 181–197.Google Scholar
Chapman, G., 1974. The skeletal system. In Coelenterate Biology: Reviews and New Perspectives (ed. L, Muscatine and Lenhoff, H.M), pp. 93–128. New York: Academic Press.Google Scholar
Hartnoll, R.G., 1967. An investigation of the movement of the scallop Pecten maximus. Helgolander Wissenschaftliche Meeresuntersuchungen, 15, 523–533.CrossRefGoogle Scholar
Harvell, C.D. & Labarbera, M., 1985. Flexibility: a mechanism for control of local velocities in hydroid colonies. Biological Bulletin. Marine Biological Laboratory, Woods Hole, Mass., 168, 312–320.CrossRefGoogle Scholar
Hughes, R.G., 1980. Current induced variations in the growth and morphology of hydroids. In Developmental and Cellular Biology of Coelenterates (ed. Tardent, P. and Tardent, R.), pp. 179–184. Amsterdam: Elsevier/North Holland Biomedical Press.Google Scholar
Knight, D.P., 1968. Cellular basis for quinone tanning of the perisarc in the thecate hydroid Campanularia (=Obelia) flexuosa Hinks. Nature, London, 218, 584–586.Google Scholar
Knight, D.P., 1970 a. Sclerotization of the perisarc of the calyptoblastic hydroid Laomedea flexuosa. 1. Identification and localisation of dopamine in the hydroid. Tissue and Cell, 2, 467–477.Google Scholar
Knight, D.P., 1970 b. Tanning cells in a thecate hydroid Campanularia flexuosa. Proceedings of the Challenger Society, 4, 60–61.Google Scholar
Lee, S.L. & Srinivasan, J. 1978. Measurement of local size and velocity probability density distributions in two-phase suspension flows by laser-doppler technique. International Journal of Multiphase Flow, 4, 141–155.Google Scholar
Nutting, C.C., 1900. American hydroids. Part 1. Plumulariidae. Special Bulletin of the Smithsonian Institute, 4, 1–285.Google Scholar
Patterson, M.R., 1984. Patterns of whole colony prey capture in the octocoral, Alcyonium siderium. Biological Bulletin. Marine Biological Laboratory, Woods Hole, Mass., 167, 613–629.CrossRefGoogle ScholarPubMed
Reidl, R., 1971. Water movement. In Marine Ecology, vol 1, part 2 (ed. Kinne, O.), pp. 1123–1156. London: Wiley Interscience.Google Scholar
Ryland, J.S. & Warner, G.F., 1986. Growth and form in modular animals: ideas on the size and arrangement of zooids. Philosophical Transactions of the Royal Society (B), 313, 53–76.Google Scholar
Vogel, S., 1981. Life in Moving Fluids. Boston: Willard Grant Press.Google Scholar
Von Schenck, D.A., 1962. Specialisation de la reproduction asexuelle de quelques hydroides vivants sur la Posidonia. Pubblicazioni della Stazione Zoologica di Napoli, supplement 32, 117–122.Google Scholar
Von Schenck, D.A., 1965. Aglaophenia harpago, a new species of the Plumulariidae (Hydroidea). Pubblicazioni della Stazione Zoologica di Napoli, 34, 211–215.Google Scholar
Warner, G.F., 1977. The shapes of passive suspension feeders. In Biology of Benthic Organisms. Proceedings of the 11th European Symposium on Marine Biology, Gal way, Ireland, 1976 (ed. Keegan, B. F, Céidigh, P. O. and Boaden, P. J. S), pp. 567–576. Oxford: Pergamon Press.Google Scholar