Ventridens suppressus
Flat dome

Key Characteristics

The shell of the flat dome is a glossy cream to pale yellow color with 5-7 whorls, and of a general dome shape. Typical width is about .3 inches. The body is approximately twice the length of the shell, with long slender eye peduncles and small tentacles.

Status and Rank

  • State Status: SC
  • State Rank: SNR
  • Global Rank: G5

Occurrences

County NameNumber of OccurrencesYear Last Observed
Genesee21947
Hillsdale11938
Ionia11947
Jackson61939
Livingston21937
Oakland2
Washtenaw41962
Distribution map for Ventridens suppressus

Updated 1/31/2017. 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.

Habitat

This species occurs among the leaf litter of mesic, rocky woodlands (Nekola 2009, Hubricht 1985).

Natural Community Types

Methodology

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.

Management

More thorough research of the distribution and specific habitat needs of the flat dome is required for management purposes. Land snails that depend on moist woodland litter may be negatively impacted by lost or trampled ground vegetation, decreased canopy cover and increased fragmentation, all of which potentially result in additional sun and wind exposure altering the microclimate of forest floors (Applegarth 1999, Walden 1995). Conservation of sizeable mesic forest tracts is therefore beneficial. Snag retention may provide important shelter to terrestrial mollusks and other invertebrates during periods of fire or drought (Applegarth 1999). Many herbicides and insecticides contain heavy metals which are rapidly bioaccumulated by snails and can alter feeding habits and prevent reproduction (Notten et al. 2006).

Active Period

Breeding from first week of May to fourth week of June

Survey Methods

As visual detection of this species is difficult, specimens are collected by litter sampling in suitable habitat. Samples are thoroughly heat-dried, soaked in water for a number of hours to separate the various components, and finally passed through a series of sieves. The shells are then able to be hand-picked from the remaining sample material (Nekola 2003).

Page Citation

Michigan Natural Features Inventory. 2007. Rare Species Explorer (Web Application). Available online at http://mnfi.anr.msu.edu/explorer [Accessed May 27, 2017]

References

Survey References

Technical References

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