Revisiting species delimitation within the genus Oxystele using DNA barcoding approach.
The genus Oxystele, a member of the highly diverse marine gastropod superfamily Trochoidea, is endemic to southern Africa. Members of the genus include some of the most abundant molluscs on southern African shores and are important components of littoral biodiversity in rocky intertidal habitats. Species delimitation within the genus is still controversial, especially regarding the complex O. impervia / O. variegata. Here, we assessed species boundaries within the genus using DNA barcoding and phylogenetic tree reconstruction. We analysed 56 specimens using the mitochondrial gene COI. Our analysis delimits five molecular operational taxonomic units (MOTUs), and distinguishes O. impervia from O. variegata. However, we reveal important discrepancies between MOTUs and morphology-based species identification and discuss alternative hypotheses that can account for this. Finally, we indicate the need for future study that includes additional genes, and the combination of both morphology and genetic techniques (e.g. AFLP or microsatellites) to get deeper insight into species delimitation within the genus.
Department of Zoology, African Centre for DNA Barcoding (ACDB), Kingsway Campus, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa.
Herman
H
Van Der Bank
KwaZulu-Natal Museum, P. Bag 9070, Pietermaritzburg 3200, South Africa, and School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, 3206 South Africa.
Dai
D
Herbert
Department of Zoology, African Centre for DNA Barcoding (ACDB), Kingsway Campus, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa.
Richard
R
Greenfield
Department of Botany and Plant Biotechnology, African Centre for DNA Barcoding (ACDB), Kingsway Campus, University of Johannesburg, PO Box 524, Auckland Park 2006, South Africa.
Kowiyou
K
Yessoufou
Gastropoda; Mollusca; Trochidae; morphology; species delimitation