Phylum:

Angustassiminea californica Class: ,

A small salt marsh snail Order:

Family: ,

Taxonomy: Defined by Tryon in 1865. Up- pearance of the two gastropods is quite simi- dated from to in lar. L. (A.) newcombiana does not have ocular 2019 (MolluscaBase 2019). peduncles. A 2nd snail common found in salt Description marshes is Ovatella myosotis, a pulmonate of Size: less than 4 mm high; most specimens rather olive shape, up to 8 mm long. It is sub- collected near 3 mm. cylindrical, not turbinate, with a short spire, Color: glossy chestnut (Keen 1971), three columellar folds, and no operculum. smooth, transparent (largest whorl); interior (See plate) porcelain-like, not pearly; spire often almost Littorine snails are larger than An- black (Coos Bay specimens); white gustassiminea, but can be superficially simi- with black markings (fig. 4). lar: sitkana, often found in this asso- Shell: ciation, is globose, almost as wide as long, Shape: 5 whorls: rounded, convex; and has either heavy striated sculpture or globose to turbinate (Keen and Coan 1974), dark horizontal lines. The animal has long ten- taller than wide; aperture subcircular, with- tacles, not Angustassiminea's unusual ocular out notch or canal; inner lip spread out as a peduncles. , the checkered small thickened callus (Keen and Coan littorine, is occasionally found in the saltier 1974) (fig. 3). parts of marshes. It is quite a bit larger than Columella: continuous with inner lip: all the preceding snails, and is patterned on no shelf, no folds, appressed to whorl. its exterior and purple inside. Spreads into callus. (fig. 3). Operculum: very thin, transparent, Ecological Information subspiral, convex (fig. 2). Range: Vancouver Island, British Columbia, Body: eyes on short ocular peduncles, no to Cabo San Lucas, Baja California (Keen tentacles: family Assimineidae (Keen 1971) 1971). (fig. 4). Radula with 3 basal cusps on both Local Distribution: Coos Bay, many stations: sides of central plate: genus An- South Slough, Haynes Inlet. gustassiminea (not figured). Habitat: under driftwood, debris, Salicornia, in mud. Possible Misidentifications Salinity: generally a wide toleration of salini- Angustassiminea californica is one of ties: to 2.4 ‰ seawater; possibly to 16 ‰ a small association of salt marsh snails. (Matthews 1979). Within our range it is often found with or Temperature: varied (salt marsh tempera- near Littorina (Algamorda) newcombiana. tures). This is a slightly larger littorine (to 6 mm) Tidal Level: family Assimineidae are intertid- with 4 whorls, a nearly circular aperture, and al4; all live above the low tide level; this spe- with a simple chink between the large whorl cies likes upper, usually dry parts of the and inner lip. The general shape and ap- marsh, about 3-4 feet (South Slough, Coos

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual : https://oimb.uoregon.edu/oregon-estuarine-invertebrates and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected]

Unknown. 1983. Angustassiminea califormica. In: Oregon Estuarine Invertebrates: Rudys' Illustrated Guide to 140 Common Species, 3rd ed. T.C. Hiebert, B.A. Butler and A.L. Shanks (eds.). University of Oregon Libraries and Oregon Institute of Marine Biology, Charleston, OR.

Bay). Associates: littorines L. sitkana, L. (A.) newcombiana, pulmonate Ovatella myoso- tis, amphipod Traskorchestia traskiana; plants: Salicornia, Distichilis, Fucus. Abundance: common in Salicornia marshes (Smith and Carlton 1975). Life-History Information Reproduction: Larva: Juvenile: Longevity: Growth Rate: Food: Predators: fish: many snails found in gut content analysis (Coos Bay) (Matthews 1979). Behavior: Bibliography 1. KEEN, A. M. 1971. Sea shells of tropical west America; marine mollusks from Ba- ja California to Peru. Stanford University Press, Stanford. 2. KEEN, A. M., and E. COAN. 1974. Ma- rine Molluscan Genera of Western North America: An Illustrated Key. Stanford University Press, Stanford, California. 3. MATTHEWS, R. 1979. A comparative study of preferred salinities among South Slough snails. Oregon Institute of Marine Biology (University of Oregon). 4. MOLLUSCABASE. 2019. MolluscaBase. Angustassiminea californica (Tryon, 1865), World Register of Marine Species at: http://www.marinespecies.org/ aphia.php?p=taxdetails&id=845921. [Accessed 3/18/2019]. Updated 1983 updated 2019 C.D. Piazzola Robbins

A publication of the University of Oregon Libraries and the Oregon Institute of Marine Biology Individual species: https://oimb.uoregon.edu/oregon-estuarine-invertebrates and full 3rd edition: http://hdl.handle.net/1794/18839 Email corrections to: [email protected]