Resolving taxonomic uncertainty in vulnerable elasmobranchs : are the Madeira skate (Raja maderensis) and the thornback ray (Raja clavata) distinct species?

Ball, RE; Serra-Pereira, B; Ellis, J; Genner, MJ; Iglésias, S; Johnson, AF; Jones, CS; Leslie, R; Lewis, J; Mariani, S; Menezes, G; Neat, F; Noble, LR; Sims, DW; Griffiths, AM

Abstract

Skates and rays constitute the most speciose group of chondrichthyan fishes, yet are characterised by remarkable levels of morphological and ecological conservatism. They can be challenging to identify, which makes monitoring species compositions for fisheries management purposes problematic. Owing to their slow growth and low fecundity, skates are vulnerable to exploitation and species exhibiting endemism or limited ranges are considered to be the most at risk. The Madeira skate Raja maderensis is endemic and classified as ‘Data Deficient’ by the IUCN, yet its taxonomic distinctiveness from the morphologically similar and more wide-ranging thornback ray Raja clavate is unresolved. This study evaluated the sequence divergence of both the variable control region and cytochrome oxidase I ‘DNA barcode’ gene of the mitochondrial genome to elucidate the genetic differentiation of specimens identified as R. maderensis and R. clavate collected across much of their geographic ranges. Genetic evidence was insufficient to support the different species designations. However regardless of putative species identification, individuals occupying waters around the Azores and North African Seamounts represent an evolutionarily significant unit worthy of special consideration for conservation management.

Citation

Ball, R., Serra-Pereira, B., Ellis, J., Genner, M., Iglésias, S., Johnson, A., …Griffiths, A. (2016). Resolving taxonomic uncertainty in vulnerable elasmobranchs : are the Madeira skate (Raja maderensis) and the thornback ray (Raja clavata) distinct species?. Conservation Genetics, 17(3), 565-576. https://doi.org/10.1007/s10592-015-0806-1

• Journal Article Type: Article
• Acceptance Date: Dec 25, 2015
• Online Publication Date: Feb 11, 2016
• Publication Date: Feb 11, 2016
• Deposit Date: Jan 15, 2019
• Publicly Available Date: Jan 15, 2019
• Journal: Conservation Genetics
• Print ISSN: 1566-0621
• Publisher: Springer Verlag
• Volume: 17
• Issue: 3
• Pages: 565-576
• DOI: https://doi.org/10.1007/s10592-015-0806-1
• Publisher URL: https://doi.org/10.1007/s10592-015-0806-1
• Related Public URLs: https://link.springer.com/journal/10592
• Additional Information: Projects : Oceans 2025 Strategic Research Programme Theme 6 (Science for Sustainable Marine Resources)