|
Ranella
australasia (Perry,
1811)
Description:
Shell heavy with two varices per whorl. Sculpture on shoulder variable;
smooth or with one or two rows of nodules, weak in shallow water shells
and strong in deep water specimens. Whole shell covered with irregular
spiral riblets. Outer lip with about nine strong, elongate teeth;
columella with a strong tooth posteriorly and, on large shells, several
lirae anteriorly. Anterior canal short. Exterior coloration uniform dark
brown, varices alternating white and brown. Interior and columella
white. Covered with a thick velvety periostracum when alive. Operculum
oval.
Size:
Up to 130 mm in length, intertidal specimens typically 80 mm.
Distribution:
Australia, New Zealand and South Africa. In Australia, from Tin Can Bay,
Qld, to Houtman Abrolhos, WA, including Tasmania.
Habitat:
On rocky shores on the open coast, intertidally and down to 350 m.
Common.
Synonym:
Iredale described the NSW deepwater form as a subspecies, Mayena
australasia benthicola Iredale, 1929, on the grounds that it has two
strong, nodulose peripheral keels, while the intertidal form generally
has only one.
Figs. 1,2: Sydney (DLB1968)
|