| Rocky mountain capshell | |
|---|---|
| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| (unranked): | clade Heterobranchia clade Euthyneura clade Panpulmonata clade Hygrophila |
| Superfamily: | Acroloxoidea |
| Family: | Acroloxidae |
| Genus: | Acroloxus |
| Species: | A. coloradensis |
| Binomial name | |
| Acroloxus coloradensis J. Henderson, 1930 |
|
Contents |
The Rocky Mountain capshell, Acroloxus coloradensis, is a very small, freshwater limpet or snail, a species of aquatic gastropod in the family Acroloxidae. It is the only member of the family Acroloxidae found in North America [2]. It has a flat shell with an apex at the back left side of the shell. Colors are typically brown and white with clear growth lines and radial striae[3]. The Rocky Mountain capshell is a pulmonate, but has developed aquatic gills so it does not rely on air to obtain oxygen. It has been known to grow up to 4.6mm long, 2.9mm wide, and 1.2 mm tall[4]
The Rocky Mountain capshell has been found in very small numbers of high altitude ponds and lakes in Colorado, Montana in the United States, and British Columbia and Alberta in Canada.[5] It has also recently been found in some slowly flowing portions of the Beaver River in Alberta, Canada[6]. The Rocky Mountain capshell is most likely to be found at elevations from approximately 8,500-10,000 feet.The Rocky Mountain capshell is exclusive to these elevations because below 8,500 feet, lake floor substrate is too fine, and above 10,000 feet, the availability of Calcium and certain ions is much lower [7].
The diet of the Rocky Mountain capshell is not well understood, but it is believed that they consume aquatic vegetation known as microphytes [8].
Like all other pulmonates, the Rocky Mountain capshell is hermaphroditic.[9]. Although the specifics of their breeding is not well-understood, the reproductive habits of other limpets may be similar. It is believed that they can either fertilize themselves or reproduce via sexual methods. Other members of Basommatophora can delay sexual maturation processes until conditions are favorable including warmer temperatures, a greater supply of food, and lower concentrations of individuals in a habitat[10].
Because of the extremely small numbers of known habitats and the susceptibility of these habitats to change from things such as recreation, timber harvesting, mining and other human-associated activities, the species has been listed as S1, or "critically imperiled", in Alberta and Montana and S2S3, or "imperiled", in Colorado and British Columbia[11]. Their endangerment level is also high because of the inabiliity of the Rocky Mountain capshell to colonize other lakes [12].
http://www.google.com/imgres?q=rocky+mountain+capshell&um=1&hl=en&sa=N&rlz=1R2ADFA_enUS458&biw=1366&bih=641&tbm=isch&tbnid=nlAZbNeu8zmiqM:&imgrefurl=http://www.arkive.org/rocky-mountain-capshell/acroloxus-coloradensis/&docid=Ekjv2hjTJofCxM&imgurl=http://cdn1.arkive.org/media/4D/4D8EC9E0-C8B2-4C6A-B253-3BB95C8EE073/Presentation.Large/Rocky-Mountain-capshell.jpg&w=650&h=433&ei=kcLhTuHyL62NigKpru2ZDw&zoom=1&iact=hc&vpx=163&vpy=190&dur=71&hovh=183&hovw=275&tx=171&ty=107&sig=114856839478409073020&page=1&tbnh=126&tbnw=165&start=0&ndsp=21&ved=1t:429,r:0,s:0 [13] http://www.google.com/imgres?q=rocky+mountain+capshell&um=1&hl=en&sa=N&rlz=1R2ADFA_enUS458&biw=1366&bih=641&tbm=isch&tbnid=i6zCbzb0mTDnBM:&imgrefurl=http://fieldguide.mt.gov/detail_IMGASK8010.aspx&docid=eSqMnYlvVLopYM&imgurl=http://mtnhp.org/thumbnail/defaultGen.aspx%253Fitemid%253D88580%2526maxWidth%253D434%2526maxHeight%253D400%2526names%253DRocky%252520Mountain%252520Capshell%252520Acroloxus%252520coloradensis%2526copyright%253DMontana%252520Natural%252520Heritage%252520Program&w=434&h=290&ei=kcLhTuHyL62NigKpru2ZDw&zoom=1&iact=hc&vpx=485&vpy=190&dur=5954&hovh=183&hovw=275&tx=171&ty=130&sig=114856839478409073020&page=1&tbnh=126&tbnw=159&start=0&ndsp=21&ved=1t:429,r:2,s:0 [14]
Bio-DiTRL, University of Alberta http://bio-ditrl.sunsite.ualberta.ca/
