THE SYSTEMATIC POSITION OF LEPTORHYNCHOIDES (KOSTYLEW, 1924) AND PSEUDOLEPTORHYNCHOIDES (SALGADO-MAL
June 27th, 2008 | by admin |THE SYSTEMATIC POSITION OF LEPTORHYNCHOIDES (KOSTYLEW, 1924) AND PSEUDOLEPTORHYNCHOIDES (SALGADO-MALDONADO, 1976), INFERRED FROM NUCLEAR AND MITOCHONDRIAL DNA GENE SEQUENCES.
The systematic relationships of acanthocephalans, including Leptorhynchoides and Pseudoleptorhynchoides, from Neartic and Neotropical regions that occur in freshwater and marine fishes are enigmatic. Leptorhynchoides (3 spp.) and Pseudoleptorhynchoides (1 sp.) are presently classified in the Rhadinorhynchidae. However, recent molecular and morphological phylogenies have challenged the monophyly of this family. Sequences of nuclear ribosomal DNA (LSU, SSU regions) and the mitochondrial cox 1 gene of Leptorhynchoides thecatus and Pseudoleptorhynchoides lamothei were used in phylogenetic analyses with available sequences of 26 other acanthocephalans. Maximum Parsimony (MP) and Maximum Likelihood (ML) analyses were identical in placing both genera in the Illiosentidae. Bootstrap analyses also indicate that placement of these genera with members of Illiosentidae is reliably supported.
Garcia-Varela M.