Gastropods

Click on photo to enlarge. Scale line in photo equals 1cm unless otherwise specified.
* Species which are commonly encountered on the beach.

Homalopoma baculum (Carpenter, 1864)
Berry Dwarf Turban
intertidal size to 5mm
northern Mexico to southern BC
This tiny species is infrequently found. The shell may be pinkish-brown to gray. It is nearly smooth with fine spiral grooves.

Colloniidae

Barkley Sound, BC Ucluelet, BC, juveniles with white bands Slip Point, WA, intertidal
Gigahomalopoma luridum (Dall, 1885)
Dwarf Turban
intertidal to subtidal northern Mexico to southern Alaska size to 10mm
This small species is infrequently found. It is commonly found under rocks in shallow water. The shell may be reddish to brown in color. It has distinct spiral cords.
(synonyms - Homalopoma luridum, Homalopoma carpenteri)

Home > Northwest Shells & Marine Life > PNW Shells & Marine Life Photos > Gastropods > Gastropods - Calliotropidae, Colloniidae,
Phasianellidae & Anatomidae

Phasianellidae

Ucluelet, BC
Eulithidium pulloides (Carpenter, 1865)
Sullied Pheasant
intertidal northern Mexico to southern BC size to 5mm
This tiny species is infrequently found due to its size. The shell may be pinkish gray and is sometimes patterned. It is found among seaweeds.
(previous name - Tricolia pulloides)

Marrowstone Island, WA, intertidal
Tricolia n. sp.
intertidal Washington to BC? size to 4mm
This is a new species of Tricolia which is in the process of being formally described. It has been found intertidally among seaweeds. Those found have been dark greenish-black to gray in color.
See article on the discovery of this species here.

Anatoma kelseyi (Dall, 1905)
subtidal, 100-2200m size to 3.5mm
northern Mexico to Alaska; Japan; West Indies to Arctic Seas; Europe
This tiny shell is white with an open slit on the body whorl. Two sharp spiral ridges circle the whorls. Our specimen was found ex pisce - in the stomach of Sole.
(previous name - Scissurella kelseyi)

Calliotropidae

offshore WA coast
Bathybembix bairdii (Dall, 1889)
Baird's Top Shell
subtidal, 10-1200m Chile to northern Alaska size to 50mm
This is infrequently seen even by divers because it prefers the deeper waters. It has a thin, olive-green periostracum and rather fragile shell.
(previous namse - Lischkeia bairdii, Turcicula bairdii)

San Juan Islands, WA
Cidarina cidaris (Carpenter, 1864)
Spiny Topsnail
subtidal, 35-300m size to 40mm
northern Mexico to central Alaska
This deep water shell has distinctive beading on its ribs and less bulbous body whorls than B. bairdii. It is also less fragile.
(previous names - Bathybembix cidaris, Lischkeia cidaris, Margarita cidaris)

Family Calliotropidae, Colloniidae,

Phasianellidae & Anatomidae