Above: specimen MNHN-IM-2000-4026 from the collection Savigny at the Muséum National d’Histoire Naturelle de Paris, France. 11,3mm. original pictures provided by M. Caballer for the MNHN (CC BY). Notice how the scales become spines in the posterior area, with an abrupt transition when passing the angulate radial ridge that helps characterize the genus.

About Cardium roseolum (14), Melvill writes: « Nearly allied to C. crenelloides, described above, but of different form, being of a squarrose contour, the posterior margin much shortened, the ventral and dorsal well-nigh parallel. The whole surface is closely scaly-ribbed; these ribs are 40 in number, of much the same character as exists in crenelloides, save that they appear more persistent and imbricate, not being of so delicate a substance. The margin of the valves also is more deeply serrate or pectinate than in the allied species, of which, indeed, it might be considered a variety, but the great differences of form and colour – a clear rose – have prompted the differentiation. » (op. cit. p.134.

Slightly crenelloides but also with a little of roseolum, this specimen was collected at 12m deep, Iskenderun Gulf, Hatay Province, SE. Turkey. 8,5mm. The species was dedicated to Mr. A. Richard (1794-1852), botanist, member of the French Academy of Sciences, creator of some genera of Orchidaceae.