The Trinity bristle snail (''Monadenia setosa'') is a species of medium-sized
land snail
A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known as ...
pulmonate
Pulmonata or pulmonates, is an informal group (previously an order, and before that a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includ ...
gastropod
The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda ().
This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...
mollusc
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...
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 to California. 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 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