Description

The shells of this family show five unusually distinctive genera, each of which has its own  popular name; e.g., Strombus ("conches"), Lambis ("spider shells"), Terebellum ("torpedos"), Tibia ("shinbone shells"), and Varicospira ("beak shells"). Many shells in the Strombidae family --particularly Strombus and Lambis, are ornamented, have colorful patterns, and they are generally solidly constructed. However, the Terebellum and Tibia genera are not typical of the other genera and tend instead to be more delicately constructed (see photo gallery, below). The Terebellum shell, for example, can be easily mistaken for an olive shell (see Olividae).

Conches and spider shells (photo gallery) have a pronounced notch at the front end, the stromboid notch, through which the gastropod protrudes its eye. A widely flared lip, sometimes larger than the main shell body, is characteristic especially for Strombus and Lambis. Mature Lambis shells typically show 4 -5 hollow spines radiating out 180 degrees or more from the flared lip (photo gallery). 

Terebellum (at right) and Tibia shells (photo gallery) do not share features common to most other conch shells and are rather unique. Nevertheless, in spite of many differences in shell morphology, the anatomy and functions of the live molluscs are common to the entire family; i.e., a narrow, peculiarly arched foot bears a relatively small operculum at its end. This arrangement enables the mollusc to kick or leap, for escaping predators, rather than gliding like most other gastropods. Also, a complex eye can be protruded from a long stout stalk at the front end. All of these features in the living animals are hall marks that clearly identify the Strombidae family, including, e.g., the Terebellum and Tibia molluscs. 

The links (at right) display the highly mobile eyes of several conches. In this family, the eyes provide keen vision --the keenest of any gastropod species. All species are tropical, and most live in the intertidal zone or below the low tide zone.

Classification

Class: Gastropoda

Clade: Littorinimorpha

Superfamily: Stromboidea

Family: Strombidae

 

Major Genera

• Genus: Lambis
• Genus: Strombus
• Genus: Terebellum
• Genus: Tibia
• Genus: Varicospira

Terebellum terebellum (Linnaeus, 1758)
Terebellum Conch

LINK --SEE LIVING CONCHES: