Examples: Scaphopods
Elephant tusk shells (Dentalium elephantinum, tusk shape, [2, p. 205])
[alpha=17, beta=80, phi=-30, mu=1, Omega=-20, A=10000, a=900, b=700, L=0]
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The class of scaphopoda is constituted by tusk shells. They are hollow, tusk-shaped shells but open at both
ends with a notch or slit at the narrow end. They are found in most seas and live on protozoa. The creatures live out their lives with the wide end
of the shell burrowed in the sand or mud; it houses the head, foot, and sticky tentacles that extend to capture single-celled prey.
Scaphopoda includes the elephant tusk shells (appropriately compared by Linnaeus to an elephant's tusk), strongly longitudinally ridged (about nine ridges).
They vary only in length and curvature.
Habitat: sand offshore, Indo-Pacific region.
[2] S. Peter Dance, Shells, Dorling Kindersley, 2002.