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    Key to Aquatic Macroinvertebrates in Utah- Single Shell

    Single Shelled Organisms - Snails 

    Snails belong to the class Gastropoda, within the phylum Mollusca, and are identified by a single shell often formed into a spiral or coil. 

    Five families of snails are commonly found in Utah.


    Hydrobiidae (spring snails)

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    Description:1-8 mm. Opening on right side of spiral. Shell is smooth with an operculum. Color is uniform, light to dark brown.

    HabitatFound in springs and rivers throughout Utah.

    Lymnaeidae (pond snails)

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    Description: 10-55 mm. Opening on right side of spiral. Shell is thin and generally has an elongate spire, no operculum. Color varies with species.

    HabitatFound in all types of freshwater habitats.

    Physidae (pond snails)

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    Description: 8-25 mm. Opening on left side of spiral, has glossy shell with raised spire and large aperture and no operculum. Color varies with species.

    HabitatFound in ponds and rivers.

     Planorbidae (orb snails)

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    Description: 2-25 mm. No obvious spiral, coil is fat, no operculum. Color varies with species.

    HabitatFound in wetlands and ditches throughout Utah.

    Thiaridae (red-rimmed melanoides, INVASIVE)

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    Description: 5-50 mm. Shell is at least twice as long as it is wide. Shell is light brown with many reddish-brown spots. Originally from the Middle East and Africa

    HabitatFound in warm springs. In Utah, this family has been collected in Fish Springs, Goshen and Gandy Warm Springs.

    Valvatidae (round-lipped snail)

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    Description: 1-3 mm. Opening on right side of spiral. Spiral is subdiscoidal. Aperture is circular, with an operculum. The outermost layer is mostly green.

    HabitatFound in streams and lakes in northern Utah.

    Viviparidae (Chinese mystery snails, INVASIVE)

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    Description: Up to 60 mm. Black pigmentation rims the entire lip, shell is smooth, thin and strong in structure. Color is uniform light to dark olive-green color

    HabitatFound partially buried in mud of lakes, ponds, ditches, or slow moving streams.

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