Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-13T01:22:40.822Z Has data issue: false hasContentIssue false
  • English
  • Français

Pallisentis rexus from the Chiang Mai Basin, Thailand: ultrastructural studies on egg envelope development and the mechanism of egg expansion

Published online by Cambridge University Press:  12 April 2024

W. Wongkham  and
P.J. Whitfield
W. Wongkham
Affiliation:
Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand:
P.J. Whitfield*
Affiliation:
School of Health and Life Sciences, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NN, UK
*
*Author for correspondence Fax: 020 7848 4195 E-mail: phil.whitfield@kcl.ac.uk
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Pallisentis rexus Wongkham & Whitfield, 1999 (Eoacanthocephala: Quadrigyridae) infects the freshwater snakehead fish, Channa striata, in the Chiang Mai Basin, Thailand. All stages of egg development within the body cavity of the female parasite were observed, using transmission electron microscopy. Changes in mature eggs after contact with water were also investigated. The mature egg has five egg envelopes separated from each other by four gaps. The fertilization membrane, which is formed first, is pushed centrifugally by other, subsequently formed, envelopes and gaps, which produces a final total shell thickness of 8–36 μm around the acanthor. The disappearance of the outermost layer and the unpleating of an adjacent inner layer causes the expansion of eggs on contact with water. The volume of an expanded egg is approximately 27 times that of an unexpanded one, but the density of eggs is reduced from a value greater than water to one almost equal to water. This is believed to aid the dispersion of eggs.

Type
Research Article
Information
Journal of Helminthology , Volume 78 , Issue 1 , March 2004 , pp. 77 - 85
Copyright
Copyright © Cambridge University Press 2004

References

Crompton, D.W.T. (1985) Reproduction. pp. 213–272 in Crompton, D.W.T. & Nickol, B.B., (Eds) Biology of the Acanthocephala. Cambridge, Cambridge University Press.Google Scholar
George, P.V. & Nadakal, A.M. (1973) Studies on the life cycle of Pallisentis nagpurensis Bhalerao, 1931 (Pallisentidae: Acanthocephala) parasitic in the fish, Ophiocephalus striatus Bloch. Hydrobiologia 42, 31–43.CrossRefGoogle Scholar
Marchand, B. (1984a) The elaboration of the acanthor shell of Acanthosentis acanthuri (Acanthocephala). Journal of Parasitology 75, 712–718.CrossRefGoogle Scholar
Marchand, B. (1984b) A comparative ultrastructural study of the shell surrounding the mature acanthor larvae of 13 acanthocephalan species. Journal of Parasitology 70, 886–901.CrossRefGoogle Scholar
Peter, W., Taraschewski, H. & Latka, I. (1991) Comparative investigations of the morphology and chemical composition of the eggshells of Acanthocephala: I Macracanthorhynchus hirudinaceus (Archiacanthocephala). Parasitology Research 77, 542–549.CrossRefGoogle Scholar
Rai, P. (1967) On four acanthocephalan parasites in freshwater fishes with description of three new species. Indian Journal of Helminthology 19, 27–44.Google Scholar
Stranack, F.R. (1972) The fine structure of the acanthor shell of Pomphorhynchus laevis (Acanthocephala). Parasitology 64, 187–190.CrossRefGoogle ScholarPubMed
Taraschewski, H. & Peter, W. (1992) Comparative investigations of the morphology and chemical composition of the eggshells of Acanthocephala: II. Palaeacanthocephala. Parasitology Research 78, 376–381.CrossRefGoogle ScholarPubMed
Taraschewski, H., Peter, W. & Latka, I. (1992) Comparative investigations of the morphology and chemical composition of the eggshells of Acanthocephala: III. Eoacanthocephala. Parasitology Research 78, 382–387.CrossRefGoogle ScholarPubMed
West, A.J. (1964) The acanthor membranes of two species of Acanthocephala. Journal of Parasitology 50, 731–734.CrossRefGoogle Scholar
Whitfield, P.J. (1973) The egg envelopes of Polymorphus minutus (Acanthocephala). Parasitology 66, 387–403.CrossRefGoogle ScholarPubMed
Wongkham, W. (1982) The life cycle of thorny head worm, Pallisentis sp. Vancleave 1928 in serpent head fish Ophiocephalus striatus (Bloch). MSc thesis, Chiang Mai University.Google Scholar
Wongkham, W. (1998) The biology and host/parasite interactions of Pallisentis sp. (Acanthocephala) from Chiang Mai, Thailand. PhD thesis, University of London.Google Scholar
Wongkham, W. & Whitfield, P.J. (1999) Pallisentis rexus n. sp. (Eoacanthocephala: Quadrigyridae) from snakehead fish, Channa striata Bloch, from the Chiang Mai Basin, Thailand. Thai Journal of Agricultural Science 32, 241–251.Google Scholar
Wright, R.D. (1971) The egg envelopes of Moniliformis dubius . Journal of Parasitology 57, 122–131.CrossRefGoogle Scholar