Family Batillariidae, Cerithiidae & Cerithiopsidae
Click on photo to enlarge. Scale line in photo equals 1cm unless otherwise specified.
* Species which are commonly encountered on the beach.
Padilla Bay, WA
Boundary Bay, BC, intertidal Boundary Bay, BC, intertidal, can be very abundant Cerithiopsidae
Oak Bay, WA,
intertidalCerithiopsis sp. 1
species gets to at least 4mm. The spiral and axial grooves form
beading. The beading is somewhat flattened, especially in the
Batillaria attramentaria (G.B. Sowerby I, 1855)
Mudflat Snail *
central California to central BC;
Japan size to 50mm
This is commonly found and can be extremely abundant in places. It was
from Japan with oyster seed. The shell has spiral ribbing and may
be uniform in color, usually gray-brown, or striped with white.
The interior of the aperture is dark. As the name suggests, it
prefers mud or muddy sand.
(synonyms - Batillaria cumingi, Batillaria zonalis, Batillaria alterima)
Cerithiopsis sp. 3
This species is similar to #2, except that the sutures between the whorls seem less impressed and the body whorl more rounded.
Dall & Bartsch, 1910
intertidal to subtidal size to at least 10mm
southern BC to central Alaska
This is infrequently found. The shell is dark with spiral ridges and pronounced beading from axial grooves.
Neostylidium eschrichtii (Middendorff, 1849)
Threaded Bittium *
intertidal to 55m northern Mexico to southern Alaska size to 20mm
is commonly found intertidally. It is the largest of the Bittiums
in our area. They are found under rocks and are often
inhabited by hermit crabs. The shell is gray to brown. It
has flattened spiral
cords and no axial grooves.
(previous names - Stylidium eschrichtii, Bittium eschrichtii, Turritella eschrichtii)
This is a recent change from Stylidium to Neostylidium. See reference - Doweld, A. (2013)
Cerithiopsis are a little understood group in the Pacific Northwest
which need further study. We do not attempt to identify them to
level at this time. Our numbering system does not correlate to
any other reference, but is simply our own way to keep track of the
types we have found. We are not sure exactly how many valid
species exist in our area.
Whiskey Creek Beach, WA
This page last revised: 4-28-2015
Campbell River, BC
Cerithiopsis sp. 2
This species gets to at least 4mm.
It is also beaded only the beads are rounded and rather prominent.