Turrid Shells of the Pseudomelatomidae Family

Four  Turrid Shells of the Pseudomelatomidae Family can be found in this website:

Phylogeny: Turrid Shells of the Pseudomelatomidae Family are gastropod mollusks in the order Neogastropoda. Neogastropods are characterized by having a long siphonal canal, a well developed siphonal notch, and a specialized radula. Many species in this order have a narrow aperture. Neogastropods are primarily marine snails and most of the well-known shell families are in this order. The Pseudomelatomidae Family is one of seventeen families in the superfamily Conoidea. Conoideans include venomous shells such as auger shells and cone shells. The Pseudomelatomidae Family contains no subfamilies, fifty-three genera, and around four hundred ninety-three species. Because of the wide range and variation within these shells, Turrid Shells have been reclassified on numerous occasions, being assigned and reassigned to different families. Shells in the Pseudomelatomidae Family are also commonly called Pseudomalatomids.

Description: Turrid Shells in this family are fusiform (spindle-shaped), with moderate to high spires. The whorls may be convex or flat-sided. Their external sculpting may be fine to coarse, spiral ridges, axial ridges, crisscross ridges (cancellate), or knobs. Many species have a fold under the suture. Their apertures are narrow. The outer lip is usually thin and smooth. The columella is smooth and may be curved or straight. Their siphonal canal may be long or just a notch. They have a pronounced posterior canal, or, at least, a subtle deflection in the growth lines in the posterior end of the outer lip of the aperture. Many have subdued coloration, but some are brightly colored or interestingly patterned. Turrid Shells generally have a corneous operculum and a thin periostracum. These shells are small to large in size, with the largest species in the Pseudomelatomidae Family reaching 10 cm (3.9 inches) in length.

Habitat and Distribution: Pseudomelatomid Turrid Shells are found on soft substrates from the intertidal zone to depths of 2,212 m (7,255 feet). They are found globally in tropical to temperate seas. Twelve species from the Pseudomelatomidae Famil are found in Mexican waters.

Natural History: Turrid Shells, like Cone Shells,  are venomous predators that utilize their uniquely designed radula as a harpoon to capture and then envenomate their prey. The venom paralyzes the prey animal. Different Turrid species have differently shaped radula that match their prey, which includes amphipods, crabs, and polychaete worms. Turrid Shells are gonochoric and reproduce sexually with internal fertilization.