Fossaria cyclostoma
Bugle fossaria

Key Characteristics

The bugle fossaria is an aquatic snail with a smooth-surfaced, conic shell that is cream to brown in color, .1 to .5 inches long, with 4-5 inflated whorls seperated by deep sutures. The spire is high and rounded and the aperature is circular in shape. The snails of this family are distinguished by wide, triangular and somewhat flattened tentacles.

Status and Rank

  • State Status: T
  • State Rank: SNR
  • Global Rank: GH


No known occurrences in Michigan

Updated 5/15/2018. Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.


A species of the water's edge, the bugle fossaria is often found on mudflats and washed-up debris (Burch 2004).

Natural Community Types


For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.

Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.


Protection of shallow-water and shoreline habitat including mudflats will benefit the bugle fossaria. Driftwood and other such natural debris should be retained. Heavy recreational disturbance may negatively impact this species. As a group, the freshwater snails of North American are highly imperiled, with 74% being classified as either extinct, endangered, threatened or vulnerable (Johnson et al. 2008). Major threats include chemical and heavy metal pollution from various point and non-point sources, and sedimentation and habitat destruction through projects such as river impoundments, dredging and channelization (Johnson 2009). Water acidification can result in extripation of aquatic snail communities (Okland 1992). Reduction in the burning of fossil fuels will decrease the impacts of acid rain on this group.

Active Period

Active from first week of June to first week of October

Survey Methods

In shallow water areas, this species is best surveyed for by vigorously shaking aquatic vegetation over a bucket to remove individual snails, or by visual search using a glass-bottomed bucket. Stones, drift wood and other shoreline debris can be picked up, searched, and replaced.

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at [Accessed Aug 17, 2018]


Technical References

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