Diodora lineata (Sowerby, 1835)
Description: Apex at anterior third, with oval shaped opening; anterior slope straight to concave, posterior slope straight to convex. Sculptured with radial ribs, alternating large and small, more numerous towards margin, crossed by simple or foliaceous concentric ribs. Margin crenulate internally. Apical opening with callus surround internally. External colour fawn with rays or patches of greenish-brown, sometimes with 10-15 radial ribs of purplish-brown. Interior white.
Size: Up to 63 mm in length, commonly 30-35 mm.
Distribution: Endemic to Australia: Southern Queensland to Port Phillip Bay, Victoria.
Habitat: Under rocks on exposed rocky shores, from low tide down to about 50 m. Subtidally, large specimens are found under ledges and in caves and crevices (Coleman, 1975). Moderately common.
Comparison: Two similar species are Diodora lincolnensis (Cotton, 1930), which occurs from Victoria to Western Australian, and Diodora jukesi (Reeve, 1849), which occurs in northern Australia, reaching as far south as Caloundra, Queensland. Both are more strongly sculptured than D. lineata.
Synonymy: Elegidion audax Iredale, 1924
Fig. 1 Terrigal, NSW (C.077275)
Fig. 2 Live animal. Terrigal, NSW (DLB5101)
Copyright Des Beechey 2005