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spiny-headed worms, thorny-headed worms

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taxon links [up-->]Polyacanthocephala [down<--]Rotifera Interpreting the tree
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The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life. The basal branching point in the tree represents the ancestor of the other groups in the tree. This ancestor diversified over time into several descendent subgroups, which are represented as internal nodes and terminal taxa to the right.

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Containing group: Rotifera

Other Names for Acanthocephala


Amin, O.M. 1985. Classification. Pages 22–71 in: Biology of the Acanthocephala. B. B. Nickol and D. W. T. Crompton, eds. Cambridge University Press, Cambridge.

Amin, O.M. 1987. Key to the families and subfamilies of Acanthocephala with the erection of a new class (Polyacanthocephala) and a new order (Polyacanthorhynchida). J. Parasitol. 73:1216–1219.

Conway Morris, S. and D. W. T. Crompton. 1982. The origins and evolution of the Acanthocephala. Biological Reviews of the Cambridge Philosophical Society 57:85–115.

Crompton, D. W. T. and B. B. Nickol, eds. 1985. Biology of the Acanthocephala. Cambridge University Press, Cambridge, UK.

Dunagan, T. T. and D. M. Miller. 1991. Acanthocephala. Pages 299–332 in: Microscopic Anatomy of Invertebrates Vol. 4, F. W. Harrison, ed., Wiley-Liss.

García-Varela, M., M. P. Cummings, G. Pérez-Ponce de León, S. L. Gardner and J. P. Laclette. 2002. analysis based on 18S ribosomal RNA gene sequences supports the existence of class polyacanthocephala (acanthocephala). Molecular Phylogenetics and Evolution 23:288-292.

García-Varelam M. and S. A. Nadler. 2005. Phylogenetic relationships of Palaeacanthocephala (Acanthocephala) inferred from SSU and LSU rDNA gene sequences. J. Parasitol. 91:1401–1409.

García-Varela, M., G. Pérez-Ponce de León, P. De la Torre, M. P. Cummings, S. S. S. Sarma and J. P. Laclette. 2000. Phylogenetic relationships of Acanthocephala based on analysis of 18S ribosomal RNA gene sequences. Journal of Molecular Evolution 50:532–540.

Garey, J. R., T. J. Near, M. R. Nonnemacher, and S. A. Nadler. 1996. Molecular evidence for Acanthocephala as a subtaxon of Rotifera. Journal of Molecular Evolution 43:287-292.

Garey, J. R., A. Schmidt-Rhaesa, T. J. Near, and S. A. Nadler. 1998. The evolutionary relationships of rotifers and acanthocephalans. Hydrobiologia 387:83-91.

Herlyn, H., O. Piskurek, J. Schmitz, U. Ehlers, and H. Zischler. 2003. The syndermatan phylogeny and the evolution of acanthocephalan endoparasitism as inferred from 18S rDNA sequences. Molecular Phylogenetics and Evolution 26:155–164.

Mark Welch, D. B. 2000. Evidence from a protein-coding gene that acanthocephalans are rotifers. Invertebrate Biology 119:17-26.

Miquelis, A., J.-F. Martin, E. W. Carson, G. Brun, and André Gilles. 2000. Performance of 18S rDNA helix E23 for phylogenetic relationships within and between the Rotifera–Acanthocephala clades. C.R. Acad. Sci. Paris, Sciences de la vie/Life Sciences 323:925–941.

Monks, S. 2001. Phylogeny of the Acanthocephala based on morphological characters. Systematic Parasitology 48:81–116.

Near, T. J. 2002. Acanthocephalan phylogeny and the evolution of parasitism. Integr. Comp. Biol. 42:668–677.

Near, T. J., J. R. Garey, and S. A. Nadler. 1998. Phylogenetic relationships of the acanthocephala inferred from 18S ribosomal DNA sequences. Molecular Phylogenetics and Evolution 10:287–298.

Nickol, B. B. and D. W. T. Crompton. 1985. Biology of Acanthocephala. Cambridge University Press, Cambridge.

Zrzavy, J. 2001. The interrelationships of metazoan parasites: a review of phylum- and higher-level hypotheses from recent morphological and molecular phylogenetic analyses. Folia Parasitologica 48:81-103.

Title Illustrations
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Scientific Name Acanthocephala
Creator Houseman
Specimen Condition Dead Specimen
Sex Male
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Citing this page:

Tree of Life Web Project. 2006. Acanthocephala. spiny-headed worms, thorny-headed worms. Version 28 July 2006 (temporary). http://tolweb.org/Acanthocephala/20452/2006.07.28 in The Tree of Life Web Project, http://tolweb.org/

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Each ToL branch page provides a synopsis of the characteristics of a group of organisms representing a branch of the Tree of Life. The major distinction between a branch and a leaf of the Tree of Life is that each branch can be further subdivided into descendent branches, that is, subgroups representing distinct genetic lineages.

For a more detailed explanation of the different ToL page types, have a look at the Structure of the Tree of Life page.

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