Aylacostoma

From Wikipedia, the free encyclopedia

Aylacostoma
Naturalis Biodiversity Center - RMNH.MOL.170199 - Aylacostoma crenocarina (Moricand, 1841) - Thiaridae - Mollusc shell.jpeg
Aylacostoma crenocarina
Scientific classification
Kingdom:
Animalia
Phylum:
Class:
(unranked):
Superfamily:
Family:
Genus:
Aylacostoma

Spix, 1827[1]
Type species
Aylacostoma glabrum Spix, 1827
Diversity[2]
32 species

Aylacostoma is a genus of tropical freshwater snails with an operculum, aquatic gastropod molluscs in the family Hemisinidae. They are found in South and Central America. As a consequence of the Yacyretá Dam, two species are entirely extinct and another is extinct in the wild.[3][4]

Species[]

Species within genus Aylacostoma include:

Distribution[]

The native distribution of this genus includes Central and South America.[2]

Life habits[]

Some species in this genus used to live in areas of white water in the Yacyretá Rapids, Paraná River, feeding on the algae that grow attached to the rocks on the bottom. The water in the area is saturated with oxygen, from the fast-moving waters.[citation needed]

Aylacostoma is a parthenogenic species: the population consists of only females, which increase in number by asexual reproduction. The females give birth to a small number of larvae, no more than three, that are born very well developed, so they have the physical strength needed to attach to a rock and resist the strong current.[citation needed]

Conservation status[]

With the building in 1993 of the Yacyretá Dam, almost all the suitable habitat for Aylacostoma living in this region was flooded. Consequently, A. guaraniticum and A. stigmaticum became entirely extinct, A. brunneum extinct in the wild (survives in captivity), and A. chloroticum restricted to single small wild population and a captive "safety" population.[3][4] The captive populations of the last two species are jointly managed by the National University of Misiones and Bernardino Rivadavia Natural Sciences Museum.[3]

References[]

  1. ^ Spix J. B. von (1827). Testacea fluviatilia quae in itinere per Brasiliam annis MDCCCXVII-MDCCCXX. page 15.
  2. ^ Jump up to: a b c Paschoal L. R. P., Andrade D. d. P. & Cavallari D. C. (2013). "First record of Aylacostoma francana (Ihering, 1909) (Gastropoda, Thiaridae) in Minas Gerais state, Brazil". 26(2): 277-281. doi:10.5007/2175-7925.2013v26n2p277.
  3. ^ Jump up to: a b c Vogler (2013). The Radula of the Extinct Freshwater Snail Aylacostoma stigmaticum (Caenofastropoda: Thiaridae) from Argentina and Paraguay. Malacologia 56 (1-2): 329-332.
  4. ^ Jump up to: a b Vogler, Beltramino, Strong & Rumi (2015). A phylogeographical perspective on the ex situ conservation of Aylacostoma (Thiaridae, Gastropoda) from the High Paraná River (Argentina–Paraguay). Zoological Journal of the Linnean Society 174(3): 487-499.
  5. ^ Pastorino G. & Darrigan G. (2011). "Aylacostoma osculati". In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. <www.iucnredlist.org>. Downloaded on 07 December 2013.

External links[]

  • Simone L. R. L. (2006). Land and freshwater molluscs of Brazil: an illustrated inventory on the Brazilian malacofauna, including neighbour regions of the South America, respect to the terrestrial and freshwater ecosystems. São Paulo: FAPESP, 390 pp.
Retrieved from ""