Oreohelix cooperi
Species of snail
From Wikipedia, the free encyclopedia
Oreohelix cooperi, also known as Cooper’s rocky mountainsnail or the Black Hills mountainsnail, is a critically endangered species of land snail that lives in the Rocky Mountain Ranges and Great Plains of North America.[2] Oreohelix cooperi is a hermaphroditic land snail that possesses low adult vagility and dispersal larvae stage.[2] Due to this spatial restriction, the decreased ability for O. cooperi to migrate leads it to being an endemic species to the Black Hills region.[3]
| Oreohelix cooperi | |
|---|---|
| |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| Order: | Stylommatophora |
| Family: | Oreohelicidae |
| Genus: | Oreohelix |
| Species: | O. cooperi |
| Binomial name | |
| Oreohelix cooperi (William Binney, 1858) | |
Physical description
Oreohelix cooperi is in the phylum Mollusca, class Gastropoda, and order Stylommatophora. Within the Oreohelix genus, there are approximately 40-70 different species of land snail.[4] Characteristics of land snails include shells that vary in height and breadth, as well as vary in roundness and flatness.[5] The parts of the shell include a body whorl, spire, and apex.[5] The size of most large mountain land snails species is >5cm.[2] For O. cooperi, differences in shell size can be attributed to environmental factors, such as varying soil calcium concentrations.[6] Differences in size of the adults could be caused by differences in average temperature as well as shell density.[6] There is little genetic structure across its geographic range.[6]
Oreohelix cooperi is hermaphroditic as are most land snails.[6] As a hermaphrodite, they possess the reproductive organs of both males and females.[7] Additionally, O. cooperi are considered ovoviviparous, which means that after fertilization and until birth, the embryos continue to grow within the adult snail.[6]
Habitat and ecology
Oreohelix cooperi lives in the Black Hills, east of the Rocky Mountains, in South Dakota and Wyoming.[2] The Black Hills region is characterized by a variety of habitats including prairie, deciduous forests, and coniferous forests.[2] This semi-arid region can maintain moisture throughout the year, which is facilitated by structural components such as down woody material.[8] The Black Hills receives its moisture from clouds coming from the west as the higher altitudes produce a rain shadow effect on the eastern slope of the range.[9] Oreohelix cooperi can occupy this region, as they prefer moist forest microhabitats with high calcium concentrations.[4]
Due to the fact that O. cooperi has low adult vagility and low dispersal at the larvae stage, they are likely to remain restricted in the Black Hills.[2] Due to this spatially restricted distribution, O. cooperi is considered an endemic species.[3] They are restricted to areas with a high concentrations of calcium, such as limestone and dolomite substrates, which allows them to maintain their shells.[3] Winters are cold, and summers are hot, as a consequence of continental climatic patterns.[9] O. cooperi is able to overwinter as well as the ability to undergo aestivation in the summer.[4]
Threats and conservation
Habitat loss is currently causing a decline in population sizes of Oreohelix cooperi.[3] Populations of O. cooperi are currently at risk due to the threats posed by fire, road-building, motorized recreation, and mining.[10] Management activities also pose a threat to populations of O. cooperi, as they could change the composition of cover provided by vegetation growth and litter, as well as ground temperature.[10] Additionally, it is also difficult to recolonize isolated populations of O. cooperi.[10] Climate change also poses a threat to O. cooperi populations, as it could lead to changes in moisture availability in the Black Forest region of South Dakota and Wyoming.[8]
Although there have been recommendations to list O. cooperi as a protected species under the Endangered Species Act (ESA), it is currently not listed.[3] Oreohelix cooperi is also not listed on the IUCN Red List. Due to habitat fragmentation and degradation, population numbers of O. cooperi continue to decline.[3]