| Sự chẩn đoán |
Shell small-sized, thin and fragile, somewhat translucent, roughly trigonal ovate in outline, with a moderately long and rather high in shape. Anterior margin of valves rather short and rounded, clearly extending forwards beyond the umbones. Ventral margin long and straightish. Outer surface of valves smoothish, with numerous concentric growth lines and a few small radial grooves in front of the umbones. Periostracum smooth and shiny, transparent, closely applied to shell surface and sometimes abraded from the umbones. Hinge line with very small crenulations in front of the umbones, along and a short way behind the ligamental margin. Anterior adductor scar present. Internal margins very thin and smooth, undulate anteriorly in relation to the outer radial sculpture. Colour: outside of shell glossy, yellowish green to olive-brown, typically patterned with about 15 narrow, tenuous, reddish brown stripes on posterodorsal slope (one of which is larger and darker), and a number of irregular transverse bands of the same colour. Interior slightly pearly, with the outer colour pattern more or less showing through. |
