Family Caecidae

Shell size to 2.5 mm; shell cylindrical, bulbous in middle. Surface smooth. Apical plug with small projection. Color translucent-white or completely transparent, with irregular opaque-white mottlings. The main (black and white) picture was taken through a scanning electron microscope (SEM).

Shell size to 2.5 mm; shell tubular, moderately curved, increasing in diameter toward anterior region, covered by typical light-brown periostracum. Sculpture of longitudinal microscopic striations visible only under high magnification. Apical plug (septum) hemispheric, mucro small, blunt. This is a scanning electron microscope (SEM) image.

Shell size to 2.5 mm; shell tubular. Sculpture of about 20 rings about twice as wide as interspaces. Apical plug (septum) slightly convex, with small, pointed projection (mucro). Color white or tan. Common in seagrass flats and sheltered areas. This is a scanning electron microscope (SEM) image.

Shell size to 2 mm; shell tubular, moderately curved, diameter constant. Sculpture of longitudinal cordlets as wide as interspaces. Aperture with ring-lke varices. Apical plug (septum) hemispheric. Mucro blunt, projecting slightly to left side. Color translucent-white. This is a scanning electron microscope (SEM) image.

Shell size to 3 mm; shell cylindrical, minute, sculpture of about 30 low rings, strong incised longitudinal lines present on entire shell. Septum not recessed, mucro very pointed, prominent, straight-sided. Color off- to brownish-white. The main (black and white) picture was taken through a scanning electron microscope (SEM).

Shell size to 4 mm; shell cylindrical, minute, sculpture variable, 20-40 strong rings distributed on entire surface, last 2-4 rings larger, interspaces proportionally larger. Fine longitudinal lines present on entire shell. Septum deep-set, mucro pointed, sharp. Color opaque-white. The main (black and white) picture was taken through a scanning electron microscope (SEM).

Shell size to 2 mm; shell cylindrical, minute, shell sculpture very variable in regard to intensity of rings, usually with about 15 rings present only on posterior part of shell, but some lacking rings altogether. Interspaces as wide as rings. Septum slightly concave, mucro not prominent, blunt. Color off-white. The main (black and white) picture was taken through a scanning electron microscope (SEM).

Shell size to 3.5 mm; shell tubular, sometimes increasing in diameter toward aperture. Shell smooth, lacking longitudinal microsculpture, glossy in well-preserved specimens. Aperture sometimes curved dorsally. Apical plug (septum) hemispheric, mucro blunt when present. The main image shows a shell collected in 1998 by Lois Dunnam at Gulfside City Park on Sanibel. The secondary illustration is a scanning electron microscope (SEM) image.