Epidirona tuberculata Laseron, 1954
Description: Whorls concave above periphery, sculptured with fine spiral ribs, about 12-15 per whorl on spire, and alternating large and small on body whorl. Row of elongate nodules on periphery, about 17-21 per whorl. Curved axial ribs cut the spiral ribs creating beads at the intersections; sculpture variable in strength from cancellate to strongly beaded. Columella smooth, outer lip with sinus of rounded V shape with apex above periphery. Aperture strongly lirate internally. Colour uniformly yellow-brown.
Size: Up to 19 mm in length.
Distribution: Endemic to Australia; Cape Moreton, Queensland, to Sydney, NSW.
Habitat: Known from 50-125 m. Uncommon.
Comparison: This species shows elongate nodules on the periphery and beading on the body whorl as with E. hedleyi, but is a smaller and more slender shell, and lacks the row of oblique nodules immediately below the suture.
Synonymy: Epidirona costifera Laseron, 1954 (NEW SYNONYM). Laseron described E. costifera as "closely related" to E. tuberculata, but differing by being "larger, the aperture relatively longer, and the sculpture is much coarser". With the greater range of specimens now available, it is clear that E. costifera is within the range of variation of size and sculpture of E. tuberculata.
Fig. 1: Off Port Hacking, NSW, in 100 m (C.371730)
Fig. 2: HOLOTYPE of Epidirona tuberculata. Off Port Stephens, NSW, 55-64 m. (Lip broken) (C.103549).
Fig. 3: HOLOTYPE of Epidirona costifera. Off Manning R., NSW, in 73-91 m (C.103551)
Copyright Des Beechey 2004