Melampus (Melampus) bidentatus Say, 1822
Eastern Melampus
- Melampus bidentatus Say 1822a: 245.
- Melampus bidentatus var. lineatus Say 1822a: 246.
- Melampus obliquus Say 1822b: 377.
- Auricula cornea Deshayes 1830–1832: 90.
- Auricula jaumei Mittré 1841: 67.
- Melampus gundlachi L. Pfeiffer 1853: 126.
- Melampus redfieldi L. Pfeiffer 1854: 112.
- Melampus bidentatus var. borealis “Conrad” L. Pfeiffer 1856: 46.
- Melampus coffeus var. alternatus C. A. Davis 1904: 127, pl. 4, fig. 11.
- Melampus coffeus var. verticalis C. A. Davis 1904: 127, pl. 4, fig. 12.
- Melampus coffeus var. bishopii C. A. Davis 1904: 127, pl. 4, fig. 13.

Identification. Shell subovate-conical. Spire rather short, conical, with sides very slightly convex. Suture very shallow, sometimes with a puckered band below. Whorls ca 6, rather flat-sided, slightly shouldered. Protoconch eroded in most. Teleoconch with weak incremental striae and coarser wrinkles. Aperture narrow, acute above, ca ¾ of shell height, with 1 submedial parietal plica, several smaller parietal plicae, and said to have outer lip with several lirae (not seen). Columella with 1 plica at base. Lip simple, thin. Parietal callus glazed, transparent, inconspicuous. No umbilicus. Shell weakly glossy, pale brown with some darker and lighter colabral streaks and 3 or 4 brown spiral bands in some. Height to ca 12 mm (higher than wide).
Animal red-brown.
Readily differentiated from Myosotella myosotis by its larger sized shell having a short, conical spire, and several darker brown spiral bands.
Habitat. Semimarine, in salt marshes; living under vegetation and driftwood.
This is a native, semimarine, salt-marsh species (Frias Martins 1996), included here to complete the family Ellobiidae.
Global range. Quebec (Bousfield 1960) and Maritime Provinces south along the Atlantic coast to, Florida Keys and the US Gulf Coast to Belize, Bahamas, Cuba, Hispaniola, and Jamaica; Bermuda (Frias Martins 1996).
Canadian range. Chaleur Bay, Quebec (Bousfield 1960), and south in New Brunswick, Prince Edward Island, and Nova Scotia.
Etymology. Latin: bi + dentatus, two-toothed.