Journal of the Marine Biological Association of the United Kingdom

Research Article

Ribosomal internal transcribed spacer regions are not suitable for intra- or inter-specific phylogeny reconstruction in haplosclerid sponges (Porifera: Demospongiae)

Niamh E. Redmonda1 and Grace P. McCormacka2 c1

a1 Department of Invertebrate Zoology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013-7012, USA

a2 Molecular Evolution and Systematics Laboratory, MRI, Zoology Department, National University of Ireland, Galway, Ireland

Abstract

Sequences of the ribosomal internal transcribed spacer regions 1 and 2 (ITS-1 and ITS-2) were employed to investigate relationships between putatively very closely related species of marine haplosclerids and to investigate the species status of Haliclona cinerea. Results indicate that intra-genomic and intra-specific levels of diversity are equivalent, and sequences from multiple clones from a number of individuals of a single species could not be separated on phylogenetic trees. As a result, the ITS regions are not suitable markers for population level studies in marine haplosclerids. Sequences of these regions were highly species specific, and large differences were found between species. ITS sequences from three Callyspongia and three Haliclona species could not be aligned successfully and therefore this locus could not be used to investigate relationships between these putative close relatives. However, ITS sequences retrieved from one H. cinerea were very different from sequences generated from other H. cinerea individuals indicating that this species comprises more than one taxon.

(Received December 11 2008)

(Accepted January 15 2009)

(Online publication June 03 2009)

Correspondence:

c1 Correspondence should be addressed to: G. McCormack, Molecular Evolution and Systematics Laboratory, MRI, Zoology Department, National University of Ireland, Galway, Ireland email: grace.mccormack@nuigalway.ie