Parvicardium trapezium
Habitat: it lives in the infralittoral zone, on coarse bottoms and among Posidonia. Distribution: this species is pointed out in Cyprus Is. and along the coasts of Turkey.
Notes: shell brittle, equivalve, oblong in outline, trapezoidal in form, valves flattened. Anterior margin is roundish while the posterior one is stretched and sharp, dorsal margin flat with umbones quite evident. On external surface there can be reckoned 24/28 radial ribs evident, spaced out by thin intercostal lines. In the posterior part ribs are spines adorned and margin is crenulated. Ground is yellowish in colour with spots brown mainly placed on dorsal margin. The most similar species is P vroomi that besides being in larger sizes, its two ends are more roundish and it has a different geographical distribution. All other Mediterranean Parvicardium are larger in sizes with valves more globose. Average measures of adult specimens are around 2.5 mm in length.