Euspira pallida (Broderip & Sowerby, 1829) Common name(s): Pallid moon snail, closed moon snail, northern moon shell, pale northern moon snail
Synonyms: Lunatia pallida, Polinices palidus, Natica clausa
Phylum Mollusca  Class Gastropoda  Subclass Prosobranchia  Order Mesogastropoda  Suborder Taenioglossa  Family Naticidae
	Euspira pallida, about 1.5 cm shell height, caught by otter trawl at 80 m depth in San Juan Channel. Was occupied by a hermit crab.
	(Photo by: Dave Cowles )

Description:  As with all moon snails, this shell is round and bulbous. In this species the umbilicus is open into just a slight slit (photo) (or sometimes absent) and the operculum is thin, horny, and translucent brown. The snail has 4 or 5 whorls at its maximum size of about 5 cm height. Color gray-brown, cream, or whitish. According to Harbo (1997) the operculum is calcarious. The snail's partly translucent body is cream-colored with dark brown spots and blotches. While still globular like a moon snail, it is slightly less spherical and its spire is slightly more pointed that that of Polinices lewisii.

How to Distinguish from Similar Species:  Natica clausa has a closed umbilicus and is browner (some consider it the same species). Polinices lewisii gets well above 5 cm height, is cream-colored, pink, or beige, has 5-6 whorls, and the umbilicus is completely covered with a large callus that spreads over much of the columella region of the body whorl.

Geographical Range:  Circumpolar in the Arctic Ocean; in the NE Pacific extends southward to northern California.

Depth Range:  Subtidal down to 2000 m.

Habitat:  Sandy bottoms.

Biology/Natural History:  Although moon snails can close up completely within their shells, they can also expand very greatly until their body, several times larger than the shell, wraps around the shell like a snowplow as they push their way through the sand searching for bivalve prey. Moon snails also lay their eggs in a distinctive, curled collar leading to the name "necklace snail" in England. The egg mas of this species has tiny protuberances.

References:

Dichotomous Keys:
  Kozloff, 1987, 1996

General References:
  Byersdorfer and Watson, 2010
  Harbo, 1997
  Lamb and Hanby, 2005
  Morris, 1966 (as Polinices pallidus)

Scientific Articles:

Web sites:

General Notes and Observations: Locations, abundances, unusual behaviors:


A view of the nearly sealed umbilicus, plus the aperture Photo by Dave Cowles, August 2023

Authors and Editors of Page:
Dave Cowles (2023):  Created original page
CSS coding for page developed by Jonathan Cowles

Salish Sea Invertebrates web site provided courtesy of Walla Walla University