Tonna

Tonna is a genus of large, predatory sea snails, marine gastropod mollusks in the family Tonnidae, commonly known as “triton’s trumpets”. They are distinguished by their heavy, thick shells that have a characteristically expanded, trumpet-like aperture. These shells are often highly prized by collectors due to their unique appearance and size.

Common Names

Common names for Tonna species include:

  • Triton's trumpet
  • Tun
  • Sea snail
  • Giant tun
  • Frog shell

Characteristics

Tonna species are characterized by their large, robust shells that are generally globular or ovoid in shape. The shell surface can be smooth or ornamented with various patterns and textures. The aperture is wide and flared, resembling a trumpet, and typically has a thick, rolled lip. The spire is usually short and blunt, often with a noticeable suture. The columella is smooth and usually has a prominent siphonal canal. The shell is generally white or cream-colored, often with brown or orange markings.

Environment

Tonna snails are found in shallow to deep waters, ranging from the intertidal zone to depths of several hundred meters. They are generally found on sandy or muddy bottoms and prefer areas with abundant prey. They are carnivores and feed primarily on echinoderms, particularly sea stars, sea urchins, and brittle stars.

References