Southwest Florida Shells
by José H. Leal
Family Chamidae
Arcinella cornuta
(Conrad, 1866)
Florida Spiny Jewelbox
Shell size up to 40 mm; shell squarish, heavy, not attached to substrate. Sculpture of 7-8 strong radial rows of tubular spines. Smaller projections on interspaces between rows of spines. Lunula large, heart-shaped. Color white, internally with pink or light-purple tints.This is a relatively common species in SW Florida. However, as is the case with many bivalve species, entire shells, aka paired valves, are difficult to find. Florida spiny jewelboxes show delicate and variable color patterns, and the species name derives from the hollow spines present on the shell. The complete shells shown in the supplementary photos were collected by Shell Museum friends Smoky Payson (left, found in 2016) and Jim Scatterday (right, found in 2007), on the east end of Sanibel. The shell on the right had been bored by a chimney clam, whose dwelling can be seen on the bottom part of the shell.