|
Click on an
image to enlarge
|
Hiatula
biradiata (W.
Wood, 1815)
Description:
Shell moderately solid. Shape elliptical-orbicular; umbo
slightly behind midline. Anterior end smoothly and broadly rounded,
ventral margin evenly convex, posterior margin more pointed than
anterior. Exterior polished or eroded dull, with weak commarginal
growth lines. Interior dull, creamish, smooth apart from
well-defined muscle scars, pallial line and pallial sinus, reaching
anterior quarter of shell. Hinge with 2 cardinal teeth in each
valve.
Ligament external, attached to nymphs that project above
dorsal margin. Shell colour creamish yellow with a few or
many broad purple or purplish brown concentric bands; 2 broad radiating
pale lines posteriorly. Periostracum
thin, smooth, brown.
Size:
Up to 80 mm in length.
Distribution:
ndemic to Australia: Iluka,
NSW, southwards and around southern Australia to Point Peron, central
WA, including Tas.
Habitat:
Lives on sand flats in sheltered and semi-sheltered localities,
probably only intertidally. Common.
Synonymy:
This species was placed in the genus Soletellina until
recently.
Remarks:
Most
specimens are eroded or covered with periostracum and do not show any
radiating lines at the posterior end.
Fig.
1: Pittwater,
Broken Bay, NSW (C.074213)
|
