Ctenoides annulata (Lamarck, 1819)

Oliver, P. Graham & Holmes, Anna, 2004, Cryptic bivalves with descriptions of new species from the Rodrigues lagoon, Journal of Natural History 38 (23), pp. 3175-3227 : 3194

Ctenoides annulata (Lamarck, 1819)

( figures 70–72 )

Material examined. Ten valves (two gold-coated) from Grand Pate´, off Port Mathurin, shell gravel, 17 m, NMW.Z.2001.061.00021.

Ctenoides annulata is a common and widespread Indo-Pacific species and is present throughout the Mascarene Islands (personal observation from museum collections) including Rodrigues. Hayami and Kase (1993) described a small species of Ctenoides from cave sites and as possible cavernicolous taxa were found in the shell gravel from Grand Pate´, Rodrigues we investigated the possibility that C. minumus or a similar species was present.

We could not convince ourselves that more than one species was present in the Rodrigues material although a few of the smaller valves had a relatively long dorsal margin and a rounded anterior profile (arrows in figure 70 ) not unlike that of C. minimus . Hayami and Kase (1993) did not compare C. minimus with juveniles of C. annulata and we suggest further study to validate the cavernicolous species.

Figures

FIGS. 70–72. Ctenoides annulata, NMW.Z.2001.061.00021, external (SEM).