Morpho-molecular delineation of structurally important reef species, the fire corals, Millepora spp., at Réunion Island, Southwestern Indian Ocean
Journal
Hydrobiologia
Journal Volume
847
Journal Issue
5
Start Page
1237
End Page
1255
ISSN
0018-8158
1573-5117
Date Issued
2020-01-23
Author(s)
Boissin, E.
Leung, J. K. L.
Denis, V.
Bourmaud, C. A. F.
Gravier-Bonnet, N.
Abstract
Looking at taxa that could dominate Anthropocene reefs, the fire corals, Millepora spp., represent compelling alternative because of their similar role than scleractinian corals. However, species identification has been the subject of much debate over the past 150 years. As they may turn as among the last refuges for reef biodiversity, it is critical to accurately delimit their species boundaries to appreciate better their resilience to future environmental conditions. Combining morphological and molecular approaches, we investigated Millepora species delimitation in Réunion Island where three species co-occur: Millepora exaesa, Millepora platyphylla and Millepora tenera. Our results showed that both pore characters and polyp morphologies successfully distinguished species. Gastropore and dactylopore numbers and diameters should be used as standard traits in Millepora. Regarding molecular delineation, the mitochondrial gene clearly segregated the species, whereas the nuclear gene showed shared haplotypes between species, likely influenced by ancestral polymorphism. Confirming the results of a recent study on Red Sea fire corals showing their distinction from the Indo-Pacific ones, we emphasize that formal re-descriptions of the Indo-Pacific M. cf. platyphylla and M. cf. exaesa are needed. Our study highlights the importance of a trait-based qualitative and quantitative approach coupled to molecular delineation, especially for structurally important reef species.
Subjects
DNA barcoding
Integrative taxonomy
Morphological identification
Species delimitation methods
Trait-based quantitative approach
Publisher
Springer Science and Business Media LLC
Type
journal article