Brachidontes sp.

Oliver, P. Graham, Holmes, Anna, Killeen, Ian, Light, Janice & Wood, Harriet, 2004, Annotated checklist of the marine Bivalvia of Rodrigues, Journal of Natural History 38 (23), pp. 3229-3272 : 3236-3237

Brachidontes sp.

Habitat. Attached to the undersides of rocks at LWMOS (low water mark of springs) in sheltered conditions.

Distribution. Known only from the harbour at Pointe Monier.

Remarks. The current confusion within the Brachidontes pharaonis complex makes species discrimination difficult especially if based on shell characters alone. However, the taxon under consideration differs from the entire range of typical B. pharaonis found elsewhere in Rodrigues. The shells are more inflated with a much stronger median angle. The sculpture is stronger and more granular and the dysodont teeth behind the ligament are very strong. There are multiple teeth below the beak rather than the single tooth seen in typical B. pharaonis . These differences can be regarded as inconclusive when considered within the great range of variation recognized for B. pharaonis . However, the anatomical character of the papillation of the posterior inhalant mantle edge appears diagnostic. In B. pharaonis from Rodrigues the papillae are large and terminate in small finger-like processes whereas in B. sp. the papillae are simple pimple-like processes. Further research on both morphological and molecular characters is required to resolve the problem.

Figured specimen. 20.0 mm, NMW.Z.1999.073.00009.

FIG. 2.