Description: Members of Order Neogastropoda have a coiled shell with a well-developed siphonal canal. Their siphon is long also (photo) and their gill is monopectinate (featherlike, but only one side develops). Rachiglossans have a radula with large rasp-like teeth which is characteristic of predators. Sexes are separate. Family Columbellidae are small, mostly tropical snails called dove snails which have shorter siphonal canals than some other neogastropods. Astyris gausapata is a small species with a well-developed spire (about 3-5 whorls in these individuals). Much of the shell is generally covered with brown, slightly rough periostracum (photo). The exterior shell has faint spiral ridges on the anterior portion of the body whorl (photo). These ridges may be quite hard to detect. The columella has either no fold or two or 3 folds. The outer lip of the aperture is not evenly curved-part of it is nearly straight (photo). The operculum is thin and horny (photo). The body is creamy or off-white with distinct black spots and a long siphon (photo). Height of shell up to 1.3 cm.
How to Distinguish from Similar Species: In Alia tuberosa the siphonal region of the shell is obviously set off from the rest of the body whorl. Alia carinata has a large spiral ridge around the upper body whorl. This ridge is often lighter-colored than the rest of the shell and gives the body whorl a distinct shoulder. Several other dove-shell species have spiral ridges visible on other parts of the shell besides the lower part of the body whorl.
Geographical Range: Southern Alaska to northern Mexico
Depth Range: Intertidal to 200 m
Habitat: These were found on eelgrass.
Biology/Natural History: Shell configuration (the protoconch, or tip of the spire) indicates that the larvae of this snail are planktonic but likely live off body reserves instead of by actively feeding in the plankton.
On the continental shelf off California, this species is a common inhabitant of sandy bottoms both within and away from small methane seeps at depths of around 50 m (Levin et al., 2000).
MacDonald et al., (2012) list this species as a facultative carnivore
on soft bottoms in the Strait of Georgia. It was one of the dominant benthic
invertebrates found in sediments off the mouth of the Columbia river (Hinton,
1998). It is also frequently reported from Cenozoic marine fossil assemblages
Kozloff, 1987, 1996 (as Alia gausapata)
Levin, Lisa A., David W. James, Christopher M. martin, Anthony E. Rathburn, Leslie H. Harris,and Robert H. Michener, 2000. Do methane seeps support distinct macrofaunal assemblages? Observations on community structure and nutrition from the northern California slope and shelf. Marine Ecology Prograss Series 208: pp. 21-39
Macdonald, Tara A., Brenda J. Burd, and Albert van Roodselaar, 2012. Facultative feeding and consistency of trophic structure in marine soft-bottom benthic communities. Marine Ecology Progress Series 445: pp 129-140. doi: 10.3354/meps09478
General Notes and Observations: Locations, abundances, unusual behaviors:
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