The Trinity bristle snail (''Monadenia setosa'') is a
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of medium-sized
land snail, a
terrestrial
Terrestrial refers to things related to land or the planet Earth.
Terrestrial may also refer to:
* Terrestrial animal, an animal that lives on land opposed to living in water, or sometimes an animal that lives on or near the ground, as opposed to ...
pulmonate gastropod mollusc in the family
Monadeniidae
Monadeniinae is a taxonomic subfamily of small to medium-sized air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family XanthonychidaeMolluscaBase eds. (2021). MolluscaBase. Monadenia Pilsbry, 1895. Accessed through: Wo ...
.
Description
The Trinity bristle snail attains a body length of approximately 2.5 cm. It is brown or chestnut-colored and covered with minuscule, translucent bristles, which give the species its common name.
Distribution and habitat
This species is
endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...
to
California
California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...
. This snail is found in northwestern Trinity County, along the Trinity River, up some of its tributaries and into the Corral Bottom area. It has a healthy population within its territory. It likes cool, wet, shady
riparian
A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks a ...
zones, and prefers areas with a deciduous understory.
Ecology
The Trinity bristle snail is dependent on cool, moist conditions, and therefore it is only active at night. It spends warmer parts of the day stuck to shady areas on tree trunks, and in especially warm parts of the summer it may not move for days. When conditions are cool enough it feeds on
lichen and the tender parts of green plants. The snail has a lifespan of over ten years, and may not reach full size for nearly that long. It is subject to predation by beetles and possibly rodents.
[
]
Survival threats
The species appears dependent on riparian habitats, and especially likes bigleaf maples (Acer macrophyllum), eating the leaves that are decomposing at the base of the trees (from observations during field work by Forest Service employee Gay Berrien who was involved with locating the snails during initial research in 1980). There have been no studies that show it ever occupied a larger area than it does now—much of the northwestern portion of Trinity County. At the edges of its territory it has been known to cross with others of the Monadenia genus
References
External links
{{Taxonbar, from=Q3075749
Monadenia
Snail
A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class G ...
Molluscs of the United States
Endangered fauna of California
Gastropods described in 1852