Phylogenetic analysis based on 18s ribosomal RNA gene sequences supports the existence of class polyacanthocephala (acanthocephala)

Martín García-Varela, Michael P. Cummings, Gerardo Pérez Ponce De León, Scott L. Gardner, Juan P. Laclette

Research output: Contribution to journalArticle

44 Scopus citations


Members of phylum Acanthocephala are parasites of vertebrates and arthropods and are distributed worldwide. The phylum has traditionally been divided into three classes, Archiacanthocephala, Palaeacanthocephala, and Eoacanthocephala; a fourth class, Polyacanthocephala, has been recently proposed. However, erection of this new class, based on morphological characters, has been controversial. We sequenced the near complete 18S rRNA gene of Polyacanthorhynchus caballeroi (Polyacanthocephala) and Rhadinorhynchus sp. (Palaeacanthocephala); these sequences were aligned with another 21 sequences of acanthocephalans representing the three widely recognized classes of the phylum and with 16 sequences from outgroup taxa. Phylogenetic relationships inferred by maximum-likelihood and maximum-parsimony analyses showed Archiacanthocephala as the most basal group within the phylum, whereas classes Polyacanthocephala + Eoacanthocephala formed a monophyletic clade, with Palaeacanthocephala as its sister group. These results are consistent with the view of Polyacanthocephala representing an independent class within Acanthocephala.

Original languageEnglish (US)
Pages (from-to)288-292
Number of pages5
JournalMolecular Phylogenetics and Evolution
Issue number2
StatePublished - Jan 1 2002



  • 18S rRNA
  • Acanthocephala
  • Polyacanthocephala
  • Polyacanthorhynchus caballeroi

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Molecular Biology
  • Genetics

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