Calyptraea fastigiata Gould, 1846 Common name(s): Cup-and-saucer snail, Pacific chinese hat snail
Synonyms:
Phylum Mollusca  Class Gastropoda   Subclass Prosobranchia    Order Mesogastropoda     Suborder Taenioglossa      Family Calyptraeidae
	Calyptraea fastigiata shell (dead) collected subtidally near Northwest Island
	(Photo by: Dave Cowles, July 2005)

How to Distinguish from Similar Species:  Slipper shells such as Crepidula adunca have a septum inside but the shells are more flattened, and the septum also is mostly flat rather than spiral.  The shells of chinese cap limpet Acmaea mitra has a similar shell shape but no septum inside.

Geographical Range:  Alaska to California

Depth Range:  Occasionally intertidal, mostly subtidal at 18 to 137 m

Habitat:  Attached to rocks, dead shells, or sometimes to crabs

Biology/Natural History:  As with other slipper shells, this species is a filter feeder with special gills.

References:

General References:

  Harbo, 1997
  Morris, 1966

Scientific Articles:
 

Web sites:
 

Inside the shell there is a spiral septum, or shelf, which twists about 1/2 revolution