The Squared Turrid
The Squared Turrid, Glyphoturris quadrata (Reeve, 1845), belongs to a relatively obscure family of marine gastropods, the Mangeliidae. Little is known about the Squared Turrid biology and feeding habits, but shells or the species are not uncommon along the shores of our barrier islands. Fully grown shells typically measure about 8 mm (1/3 inch). The two shells in the photos represent, on the left, a fully mature individual, and, on the right, an immature one. The main difference, other than the larger size of the mature shell, lies in its fully developed outer lip, or outer margin of the shell opening (arrow), in contrast to the thin outer lip of the immature shell. This shell-shape difference between the adult and juvenile shells can be seen in many, distinctive families of gastropods, including the true Conchs (family Strombidae) and Helmet shells (family Cassidae).
The Squared Turrid, Glyphoturris quadrata (Reeve, 1845), left mature shell; right, immature shell. Arrow points to thickened outer lip on adult shell. Shell sizes not to scale. Photos by José H. Leal.