Langbahn Team – Weltmeisterschaft

Laevapex

Laevapex
Scientific classification
Kingdom:
Animalia
Phylum:
Mollusca
Class:
Gastropoda
(unranked):
clade Heterobranchia
clade Euthyneura
clade Panpulmonata
clade Hygrophila
Superfamily:
Planorboidea
Family:
Planorbidae
Subfamily:
Planorbinae
Tribe:
Ancylini
Genus:
Laevapex

Type species
Ancylus fuscus
C. B. Adams, 1841
Species

See text

Laevapex is a genus of small, freshwater, air-breathing limpets, aquatic pulmonate gastropod molluscs in the family Planorbidae, the ram's horn snails and their allies.[2]

Geographic distribution

The genus has a New World distribution. It is widespread throughout the eastern United States, occurring in lakes and slow-flowing rivers.[3]

Anatomy

These animals have a pallial lung, as do all pulmonate snails, but they also have a false gill or "pseudobranch" which can serve perfectly well as a gill when they are unable to reach the surface for air.[3]

Members of this genus are characterised by their smooth apex.[3]

Species

Species within the genus Laevapex include:[1][2][4]

Walther (2008) considers North American Laevapex monotypic, collectively synonymising L. diaphanus, L. peninsulae and unidentified Laevapex sp. with L. fuscus, the type species.[3]

References

  1. ^ a b "Laevapex Walker, 1903". Integrated Taxonomic Information System. Retrieved 29 June 2014.
  2. ^ a b Roskov Y.; Kunze T.; Orrell T.; Abucay L.; Paglinawan L.; Culham A.; Bailly N.; Kirk P.; Bourgoin T.; Baillargeon G.; Decock W.; De Wever A.; Didžiulis V. (eds.). "Laevapex". Species 2000 & ITIS Catalogue of Life, 2014 Annual Checklist. Species 2000: Naturalis, Leiden, the Netherlands. Retrieved 29 June 2014.
  3. ^ a b c d Walther, A. C. (2008). "E Pluribus Unum: A Phylogenetic and Phylogeographic Reassessment of Laevapex (Pulmonata: Ancylidae), a North American Genus of Freshwater Limpets". A systematic study of North American freshwater limpets (Gastropoda: Hygrophila: Ancylidae) (PDF) (Ph.D. thesis). The University of Michigan.
  4. ^ dos Santos; S. B. (2003). "Estado atual do conhecimento dos ancilídeos na América do Sul (Mollusca: Gastropoda: Pulmonata: Basommatophora)" [Current state of knowledge of ancylids in South America (Mollusca: Gastropoda: Pulmonata: Basommatophora)] (PDF). Revista de Biología Tropical (in Portuguese). 51 (3): 191–223. Retrieved 29 June 2014.

"Laevapex: Pictures". The Animal Diversity Web - University of Michigan.


Quelle: http://en.wikipedia.org/wiki/Laevapex