Invertebrate Systematics Invertebrate Systematics Society
Systematics, phylogeny and biogeography
RESEARCH ARTICLE

Antarctic Tardigrada: a first step in understanding molecular operational taxonomic units (MOTUs) and biogeography of cryptic meiofauna

Paul Czechowski A B C I , Chester J. Sands C I , Byron J. Adams D , Cyrille A. D’Haese E , John A. E. Gibson F , Sandra J. McInnes C and Mark I. Stevens B G H I
+ Author Affiliations
- Author Affiliations

A University of Leipzig, Molecular Evolution and Animal Systematics, Talstrasse 33, 04103 Leipzig, Germany.

B School of Earth and Environmental Sciences, University of Adelaide, SA 5005, Australia.

C British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK.

D Department of Biology, Brigham Young University, Provo, UT 84602-5181, USA.

E UMR 7205 CNRS, Origine, Structure et Evolution de la Biodiversite, Departement Systematique et Evolution, Museum national d’Histoire naturelle, CP50 – Entomologie, 75231 Paris cedex 05, France.

F Institute of Marine and Antarctic Studies, University of Tasmania, Private Bag 129, Hobart, Tas. 7001, Australia.

G South Australian Museum, GPO Box 234, Adelaide, SA 5000, Australia.

H Corresponding author: Email: mark.stevens@samuseum.sa.gov.au

I These authors contributed equally

Invertebrate Systematics 26(6) 526-538 https://doi.org/10.1071/IS12034
Submitted: 30 April 2012  Accepted: 4 October 2012   Published: 19 December 2012

Abstract

Recent studies have suggested that some resident Antarctic biota are of ancient origin and may have been isolated for millions of years. The phylum Tardigrada, which is part of the Antarctic terrestrial meiofauna, is of particular interest due to an impressive array of biochemical abilities to withstand harsh environmental conditions. Tardigrades are one of the few widespread Antarctic terrestrial animals that have the potential to be used as a model for evolution and biogeography on the Antarctic continent. We isolated 126 individual tardigrades from four geographically isolated soil samples from two remote nunataks in the Sør Rondane Mountains, Dronning Maud Land, Antarctica. We examined genetic variation among individuals utilising three gene regions: cytochrome c oxidase subunit I gene (COI), 18S rDNA (18S), and the wingless (Wg) gene. Comparison of sequences from worldwide and Antarctic tardigrades indicated long-term survival and isolation over glacially dominated periods in ice-free habitats in the Sør Rondane Mountains.


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