Cassidae

Semicassis thomsoni

(Brazier, 1875)

Adult shell from 36 to 88 mm in length, globose, moderately thin- to thick-shelled, spire short, with noduled shoulders, and colored with tan-brown and irregidar reddish brown spots. Whorls 8 or 9. Nuclear whorls bulimoid, relatively large, 4 smooth, tan or whitish, and followed by finely cancellate postnuclear whorls. Body whorl usually shouldered by 1, 2, or 3 spiral cords which may be finely or coarsely beaded or noduled. Base of body whorl bears 4 to 12 spiral, incised lines. True umbilicus open and deep; false umbilicus at the base of the columella is closed or slit-like. Left edge of columella strongly arched. Right or inner edge bears numerous, irregular plicae. Outer lip recurved, usually smooth, but may bear a few to many minute teeth. Tip of siphonal canal bears a very weak, brown splotch. Color spots on body whorl irregular in size and usually occurring in 3 to 5 spiral rows. Operculum fan shaped; transluscent yellow brown.

[[Indo Pacific Mollusca, Vol 2 No 9. 1968. p12-677]

East of Moreton island

Trawled from 117m depth
59 mm

Off Caloundra

Trawled from 117m depth
56 mm
Collected 2014

East of Cape Moreton
Moreton island

140-170m depth
Trawled
62 mm