Haplotrematidae

Haplotrematidae is a taxonomic family of predatory air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Haplotrematoidea.^[2]

Distribution

These are North American land snails. They occur from Alaska, through British Columbia, and as far south as northern Mexico, but they are predominantly snails of the eastern and western United States.^[3]

Three views of a shell of *Haplotrema vancouverense* from W. G. Binney^[4]

Shell description

Their shells vary in size from small (7 mm in diameter, or about 0.3 inches) to medium (32 mm, about 1.3 inches), usually with a low, flattened spire, a very wide umbilicus, and usually with the upper lip margin (at the aperture) curving downwards or straightened.

Anatomy

They have a number of anatomical peculiarities.

The structure of the radula of these snails (their "teeth") is unusual. Essentially, haplotrematids have fewer cusps than most snails, but they are considerably elongated, suitable for the predatory life they follow. Members of this family have been given the common name "lancetooth" snails, presumably based on this last anatomical characteristic. Their sole food source consists, as far as is known, of other terrestrial mollusks.^[5]^[3]

In this family, the number of haploid chromosomes lies between 26 and 30 (according to the values in this table).^[6]

Genera

Genera within the family Haplotrematidae include:

Subfamily Austroselenitinae H. B. Baker, 1941

Austroselenites Kobelt, 1905
Zophos Gude, 1911^[7]

Subfamily Haplotrematinae H. B. Baker, 1925

Ancomena H. B. Baker, 1931
Ancotrema H. B. Baker, 1931
Greggiella H. B. Baker, 1941
Haplotrema Ancey, 1881

Synonyms

Moerchia E. von Martens, 1860: synonym of Zophos Gude, 1911 (invalid: junior homonym of Moerchia A. Adams, 1860 [published earlier])
Selenites P. Fischer, 1878: synonym of Zophos Gude, 1911
Proselenites Thiele, 1927: synonym of Haplotrema (Geomene) Pilsbry, 1927 represented as Haplotrema Ancey, 1881

References

^ Baker, Horace B. (1931). Proc. Acad. Nat. Sci. Philadelphia 82: 405.
^ MolluscaBase eds. (2021). MolluscaBase. Haplotrematidae H. B. Baker, 1925. Accessed through: World Register of Marine Species at: http://marinespecies.org/aphia.php?p=taxdetails&id=994703 on 2021-02-21
^ a b Pilsbry, Henry A. 1946. Land Mollusca of North America (North of Mexico). Acad. Nat. Sci. Philadelphia, Monograph 3, vol. 2(1): 201-230.
^ Binney, William G. 1878. The Terrestrial Air-Breathing Mollusks of the United States and Adjacent Territories of North America. Vol. 5 (plates). Bull. Mus. Comparative Zool., Harvard. Plate 20.
^ http://www.xerces.org/Wings/spring2003.htm Archived 2007-12-06 at the Wayback Machine Atkinson, Jim. Wings: Spring 2003. Living in a World of Tastes and Smells.
^ Barker G. M.: Gastropods on Land: Phylogeny, Diversity and Adaptive Morphology. in Barker G. M. (ed.): The biology of terrestrial molluscs. CABI Publishing, Oxon, UK, 2001, ISBN 0-85199-318-4. 1-146, cited pages: 139 and 142.
^ Gude (1911). Proc. malac. Soc. London 9: 269.

Bouchet P., Rocroi J.P., Hausdorf B., Kaim A., Kano Y., Nützel A., Parkhaev P., Schrödl M. & Strong E.E. (2017). Revised classification, nomenclator and typification of gastropod and monoplacophoran families. Malacologia. 61(1-2): 1-526

External links

Media related to Haplotrematidae at Wikimedia Commons