Shell to 60 mm. Inequilateral. Outline subtrapezoidal, slightly expanded posteriorly; anterior and posterior margins evenly rounded; ventral margin straight or slightly sinuous; byssal gape narrow. Dorsal area narrow, entirely covered by ligament. Sculpture of low radial riblets with narrower interspaces; riblets slightly dissected by concentric lines but scarcely nodulose. Periostracum confined to rib interspaces, spicate, dark brown. Hinge line slightly curved, teeth in a single series increasing in size laterally. Colour white. Habitat: Attached to rocks .

Barbatia decussata (Sowerby, 1833) Shell elongate ovate, rather flat, 31.1 mm in height, 50.5 mm in length and 20.0 mm in breadth; anterior side very short, posterior wide and rather expanded, both sides rounded, slightly angulated at the upper, ventral margin slight gape; ligamental area very nar- row, bent inward, almost concealed; surface with numerous irregular radial riblets crossed by concentric lines, forming reticulate sculpture; white, covered with a scaly bristly epidermis toward the margin. Distribution: Fujian (Dongshan) Province to Hainan and Taiwan Provinces of China; Indo-Western Pacific region. Ecology: Found attached to rocks or coral reefs by byssus from the intertidal zone down to several tens of meters deep, common in South China coasts.

Barbatia decussata:
Periostracum spicate, outline with lateral margins evenly curved no auriculation, sculpture with ribs wider than interspaces but not nodulose.
Barbatia foliata:
Periostracum lamellar, outline with lateral margins straight with slight auriculations, sculpture with ribs narrow, elevated, nodulose

Throughout the Red Sea.