Solariorbis infracarinatus (Gabb, 1881) is a member of the microgastropod family Tornidae with ample distribution in the Caribbean and Gulf of Mexico, found also along the coast of Southwest Florida. Larger shells of the species reach only about 2.0 mm (about 0.08 inch). The shell has a low spire, and the shell periphery (outer shell “edge”) bears a strong spiral keel. The shell base has about 4–5 spiral ribs, but the spire itself lacks any major, visible sculpture. The protoconch projects above the remainder of the shell. The umbilicus is wide, and is flanked internally by a strong spiral ridge. The shell color is translucent-white. The shell illustrated was collected in 1994 by Vivienne Smith, 14 miles off the Sanibel Lighthouse. Original shell identification by Harry G. Lee.