Ellobiidae Explained

Ellobiidae, common name the hollow-shelled snails, is a family of small air-breathing land snails, terrestrial pulmonate gastropod mollusks in the clade Eupulmonata.^[1] Ellobiidae is the only family in the superfamily Ellobioidea, according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).

Anatomy

In this family, the number of haploid chromosomes lies between 16 and 20 (according to the values in this table).^[2]

They have a distinctive mode of locomotion arising due to a split sole. The front part of the sole adheres to the substrate and then the rear part of the sole is drawn up to the front part.^[3]

Taxonomy

Species are traditionally classified into five taxonomic groups, the Pythiidae, the Laemodontidae, the Melampodidae, the Ellobiidae and the Carychiidae. These taxa have been recognized either as families within Ellobioidea or as sub-families within the family Ellobiidae.

The family Ellobiidae consists of the following subfamilies (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005):

• subfamily Ellobiinae Pfeiffer, 1854 (1822)
• subfamily Carychiinae Jeffreys, 1830
• subfamily Melampinae Stimpson, 1851 (1850)
• subfamily Pedipedinae P. Fischer & Crosse, 1880
• subfamily Pythiinae Odhner, 1925 (1880)
• † subfamily Zaptychiinae Wenz, 1938

The high degree of homoplasy in morphological characters and frequent low variability has led to the description of approximately 800 species names available in the literature, of which 250 are likely to be valid.

A molecular study by Dayrat at al. (2011)^[4] for the Ellobioidea suggests a monophyletic origin of the entire group.

Genera

Genera within the family Ellobiidae include:

subfamily Ellobiinae

• Blauneria Shuttleworth, 1854
• Ellobium Röding, 1798

subfamily Carychiinae

• Carychium O. F. Müller, 1773
• Zospeum Bourguignat, 1856

subfamily Melampinae

• Melampus Montfort, 1810

subfamily Pedipedinae

• Creedonia Martins, 1996
• Leuconopsis Hutton, 1884
• Marinula King & Broderip, 1832
• Microtralia Dall, 1894
• Pedipes Férussac, 1821
• Pseudomelampus Pallary, 1900
• Sarnia H. Adams & A. Adams, 1855 (temporary name)

subfamily Pythiinae Odhner, 1925

• Allochroa Ancey, 1887
• Auriculastra Martens, 1880
• Cassidula Gray, 1847
• Laemodonta Philippi, 1846
• Myosotella Monterosato, 1906
• Ophicardelus Beck, 1838
• Ovatella Bivona, 1832
• Pleuroloba Hyman, Rouse & Ponder, 2005
• Pythia Röding, 1798 - type genus of the subfamily Pythiinae.

† subfamily Zaptychiinae

• † Zaptychius Walcott, 1883 - type genus of the subfamily

subfamily ?

• Auriculinella Tausch, 1886
• Auriculodes Strand, 1928
• Blauneria Shuttleworth, 1854
• Detracia Gray in Turton, 1840
• Tralia Gray, 1840

Genera brought into synonymy:

• Alexia Leach in Gray, 1847: synonym of Myosotella Monterosato, 1906
• Auricula Lamarck, 1799: synonym of Ellobium Röding, 1798
• Cremnobates Swainson, 1855: synonym of Marinula King & Broderip, 1832
• Jaminia T. Brown, 1827: synonym of Myosotella Monterosato, 1906
• Kochia Pallary, 1900: synonym of Myosotella Monterosato, 1906
• Laimodonta H. Adams & A. Adams, 1855: synonym of Laemodonta Philippi, 1846
• Leuconia Gray, 1840: synonym of Auriculinella Tausch, 1886
• Leucopepla Peile, 1926: synonym of Auriculinella Tausch, 1886
• Leucophytia Winckworth, 1949: synonym of Auriculinella Tausch, 1886
• Monica H. Adams & A. Adams, 1855: synonym of Ovatella Bivona-Bernardi, 1832
• Nealexia Wenz, 1920: synonym of Myosotella Monterosato, 1906
• Phytia: synonym of Pythia Röding, 1798
• Pira H. & A. Adams, 1855: synonym of Melampus Montfort, 1810
• Plecotrema H. Adams & A. Adams, 1854: synonym of Laemodonta Philippi, 1846
• Rangitotoa Powell, 1933: synonym of Microtralia Dall, 1894

Taxonomic note:Genus Sarnia H. Adams & A. Adams, 1855 (temporary name, Sarnia [H. & A. Adams, 1855 (September), The Genera of Recent Mollusca, 2: 239''] is an incorrect subsequent spelling of Siona H. Adams & A. Adams, 1855 which is a junior homonym of Siona Duponchel, 1829 [Lepidoptera].)

Ecology

The taxon Ellobioidea comprises a group of morphologically and ecologically highly diverse snails, known to have successfully invaded the marine, brackish water and terrestrial habitats.

These are mostly snails that live in salt marshes and similar maritime habitats, and thus have a tolerance for saline conditions.

References

This article incorporates CC-BY-2.0 text from the reference^[5]

Notes and References

1. Bouchet, P. (2012). Ellobiidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=198 on 2012-08-19
2. 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, . 1-146, cited pages: 139 and 142.
3. Book: Herbert,dai and, Kilburn, Dick. Field Guide to the Land Snails and Slugs of Eastern South Africa. 2004. Natal Museum. Scottsville, South Africa. 0-620-32415-5. 98.
4. Dayrat B., Conrad M., Balayan S., White T. R., Albrecht C., Golding R., Gomes S., Harasewych M. G., de Frias Martins A. M. (2011). "Phylogenetic relationships and evolution of pulmonate gastropods (Mollusca): new insights from increased taxon sampling". Molecular Phylogenetics and Evolution 59: 425-437. .
5. Weigand A. M., Jochum A., Slapnik R., Schnitzler J., Zarza E. & Klussmann-Kolb A. (2013). "Evolution of microgastropods (Ellobioidea, Carychiidae): integrating taxonomic, phylogenetic and evolutionary hypotheses". BMC Evolutionary Biology 13: 18. .