Phylogeny of some systematically uncertain urostyloids--Apokeronopsis, Metaurostylopsis, Thigmokeronopsis (Ciliophora, Stichotrichia) estimated with small subunit rRNA gene sequence information: discrepancies and agreements with morphological data

Eur J Protistol. 2008 Nov;44(4):254-62. doi: 10.1016/j.ejop.2007.12.002. Epub 2008 Jun 5.

Abstract

The small subunit rRNA (SSrRNA) genes of seven species of urostyloids representing four genera were sequenced. These were: Apokeronopsis crassa, A. bergeri, Anteholosticha sp-QD-1, Metaurostylopsis sp-QD-1, M. sp-QD-2, M. sp-QD-3 and Thigmokeronopsis sp-QD-1. Gene trees were constructed in order to investigate their phylogenetic relationships. The results indicate that: (1) Apokeronopsis, Thigmokeronopsis and Metaurostylopsis form a well-supported, clearly isolated, monophyletic group; (2) Metaurostylopsis species analysed consistently group together indicating that it is a well-outlined genus; (3) the validity of the genus Apokeronopsis is supported; (4) the separation of Holosticha and Anteholosticha is supported although Anteholosticha species exhibit a high molecular diversity; (5) Pseudokeronopsis and Thigmokeronopsis, which have been considered closely related, may not share a recent common ancestor, casting doubt on the monophyly of the family Pseudokeronopsidae.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Ciliophora / classification*
  • Ciliophora / cytology
  • Ciliophora / genetics*
  • Molecular Sequence Data
  • Phylogeny*
  • RNA, Protozoan / genetics*
  • RNA, Ribosomal / genetics*

Substances

  • RNA, Protozoan
  • RNA, Ribosomal