Giant tun

Tonna galea

Family Tonnidae - tun shells

Distinguishing
Characteristics
Gastropod (1 shell); shell spiral in shape; color white to light brown, sometimes mottled; body whorl makes up most of shell; grooves (sutures) between whorls deep; spire small; spiraling ribs, some alternating between high and low ribs; aperture large, outer margin scalloped, ridge near outer margin in adults; columella (central axial part) twisted with a ridge on outer margin; short, abrupt siphonal canal.
Similar Species
Similar to the partridge tun (T. pennata) which is narrower and has a higher spire.
Habitat
Gulf and bay, sandy bottoms
Maximum Size
16 cm (6 1/3 in)
Other Common Names
Previous Scientific Names
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