Field of Science

Cochlespira

Shell of Cochlespira radiata, photographed by Jan Delsing.


This beauty is a member of the genus Cochlespira, another one of the conoid shells previously classed as 'turrids' (it now belongs in the family Cochlespiridae since the disassembly of Turridae in the broad sense). Cochlespira species can be relatively large as conoids go, reaching lengths of up to five centimetres. They are found in deep waters in various parts of the world, with a fossil record going back to the Eocene (Powell 1966; Powell treated the western Atlantic species as a separate genus Ancistrosyrinx, but this and the Indo-Pacific Cochlespira have since been synonymised). One of the genus' more distinctive features is a little hard to miss: that eye-catching keel around the outside of the whorls, ornamented with serrations or spines.

As with other deep-water conoids, our knowledge of how Cochlespira species live their lives seems to be pretty limited. The radula has a broad-based central tooth with a single median cusp, and a pair of marginal teeth that are elongate but not as slender as those of many other conoids (Powell 1966). The rhynchodeal walls in the foregut are muscular and the proboscis is long. The venom glands are well-developed but join the oesophagus at about its midlength rather than in the buccal mass (Simone 1999). The arrangement looks to my admittedly inexpert eyes like it might be suited for sucking up invertebrate prey, perhaps something that might be expected to be relatively slow-moving or soft-bodied.

REFERENCES

Powell, A. W. B. 1966. The molluscan families Speightiidae and Turridae. An evaluation of the valid taxa, both recent and fossil, with lists of characteristic species. Bulletin of the Auckland Institute and Museum 5: 1-184.

Simone, L. R. L. 1999. The anatomy of Cochlespira Conrad (Gastropoda, Conoidea, Turridae) with a description of a new species from the southeastern coast of Brazil. Revista Brasileira de Zoologia 16 (1): 103–115.

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