The Bipartite Caecum
The Bipartite Caecum, Caecum bipartitum de Folin, 1870, is one of about ten species of the family Caecidae known from our shores. Members of this family have small, tube-like shells that undergo a few changes in shape during the growth of the snail. The Bipartite Caecum grows only to 2 millimeter (0.08 inch) and has its shell festooned with narrow rings, which may sometimes be present only on the posterior (wider) part of the shell or, in some cases, be completely lacking. The two images are of shells of the same size. The photo on the left was taken under a powerful scanning electron microscope (SEM). SEM images show great detail, but lack color or any indication of transparency.
The Bipartite Caecum, Caecum bipartitum, both from from Sanibel. The photo on the left was taken under a scanning electron microscope. Photos by José H. Leal.