Amphissa columbiana Dall 1916

How to Distinguish from Similar Species: Look carefully for the small folds on the columella as well as the outer lip of the aperture in order to key this species to the right family. Amphissa versicolor grows to only 1.5 cm and the axial ribs are angled instead of aligned with the length of the shell and it may have a pattern of light and dark markings. Amphissa reticulata, a rare subtidal species, has the middle third of the outer lip of the aperture rounded and also only gets to 1.5 cm long. In several other members of Family Columbellidae the spiral ridges are found only on the anterior portion of the body whorl.

Rocky to muddy beaches and subtidally.

Geographical Range: Kodiak Island, Alaska to San Pedro, California. Common in the Puget Sound area and the outer Northwest coast. In California A. versicolor is more common.

Like other members of Family Columbellidae, this species has a siphonal notch. It has both axial ribs and spiral ridges on all whorls. Amphissa columbiana has broad axial ribs and finer spiral ridges. The axial ribs are distinct on the upper half of the body whorl but nearly absent from the lower half, leaving only spiral ridges at the anterior end. The aperture is elongated, about 1/2 the length of the shell, is wider or at least not appreciably narrower at the anterior end, and there is a series of folds both on the columella and on the inside of the outer lip of the aperture. The operculum is not calcified. The middle third of the outer lip of the aperture is parallel to the long axis of the shell in adults. The whorls, of which there are usually about 5, are rounded. The next to last whorl has 20-24 axial ribs. Length to 3 cm. May be pink, orange, mauve, yellow, yellowish green, or mottled with brown. The animal is white with darker spots.

Biology/Natural History: This species is mainly a scavenger on dead flesh and dead algae, which it uses its long siphon to find. May be found in Enteroctopus dofleini middens consuming the scraps left from discarded octopus meals. It is a very active snail. When moving, a single muscular wave moves along the foot from front to back. They climb well, and often rear up on the back of the foot to feel for new substrate. A gland on the rear of the foot secretes a thick mucus strand which the animal can use to suspend itself in the water. Females attach vase-shaped capsules to rocks. Each capsule contains about 60 white eggs. The empty shells are often used by hermit crabs.In a study on San Juan Island, Pernet found that different individuals of this species matured at very different sizes. Immature individuals were characterized by shells in which the outer aperture was thin and easily broken. These individuals were still growing. Mature individuals had outer apertures which were much thicker, and were growing little or not at all even if they were not as large as some other immature individuals which were still growing. Pernet concluded that this species has determinate growth. Exposure in the lab to effluent from Cancer productus did not affect the shell form or thickness, suggesting that the large range of sizes at maturity is not due to a response to predation by the crab.

Depth Range: Intertidal to 29 m.

Amphissa columbiana, known as the wrinkled dove snail, wrinkled amphissa, or Columbian amphissa, is a species of sea snail native to the western coast of North America, from California to Alaska.

Unalaska, Aleutian Islands, Alaska, to Point Conception, Santa Barbara County, California.