Sliced snails
| Sliced snails | ||||||||||||
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White pancake snail ( Lucilla singleyana ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Helicodiscidae | ||||||||||||
| Pilsbry , 1927 |
The disk snails (Helicodiscidae) are a family of snails from the suborder of the land snails (Stylommatophora). They are mostly small, flat-shelled species. About 20 species of the family are currently known.
features
The right-hand wound cases are relatively small (less than 5 mm in diameter) and strongly flattened to almost disc-shaped. Usually only about 4 turns, max. six turns formed. The embryonic turns have very fine spiral strips or points, the later turns mostly strong spiral knots or spiral strips. The cases are seldom smooth. Teeth or lamellae protrude into the mouth, but some species may be missing. The teeth are periodically resorbed and reformed as they grow. The navel is very wide and open.
Most forms are known to be blind and no longer have eyes, an adaptation to their subterranean way of life. The jaw consists of numerous, very narrow vertical plates. The pedal and suprapedal pits unite on the rear end of the foot. The kidneys are roughly rectangular or roughly triangular in shape, and the rectal lobe is poorly developed or absent.
The prostate and uterus are united in the genital apparatus. The spermatic duct emerges in the distal part of the ovarian duct. The epiphallus is very short or not developed. The vas deferens enter the penis / epiphallus apically or laterally. The inner surface of the penis is smooth or has a pair of stimulators. A penile blind sack may or may not be present. The penile retractor attaches to the epiphallus, if present, or to the distal end of the penis. The base of the stem of the spermathec is not enlarged.
Geographical distribution, occurrence and way of life
The family is native to the West Indies , Central and North America , Western Europe , Madeira , the Philippines , Indonesia , New Guinea , the Solomon Islands , New Caledonia, and Northern Australia . Two species were also introduced to Germany. Many species live in the earth and therefore have their eyes reduced.
Taxonomy
The taxon was established by Henry August Pilsbry in a work published by Horace Burrington Baker in 1927. The Helicodiscidae family is counted among the superfamily of the Punctoidea . Some authors only recognize their subfamily status and place them in the family of point snails (Punctidae). The Treatise on Recent Terrestrial Pulmonate Molluscs. Part 8 and the MolluscaBase divide the family into two subfamilies: Helicodiscinae Pilsbry, 1927 and Stenopylinae Thiele, 1931.
- Family slugs (Helicodiscidae Pilsbry, 1927)
- Subfamily Helicodiscinae Pilsbry, 1927
- Genus Chanomphalus Strebel & Pfeffer, 1880
- Genus Helicodiscus Morse, 1864 (with the subgenera H. (Hebetodiscus) Baker, 1929, H. (Helicodiscus) Morse, 1864, H. (Pseudiscus) Morrison, 1942 and H. (Troglodiscus) Hubricht, 1962)
- Genus Polygyriscus Pilsbry, 1948
- Genus Speleodiscoides Smith, 1957
- Subfamily Stenopylinae Thiele, 1931
- Genus Microphyura Ancey, 1882
- Genus Stenopylis Fulton, 1914
- Subfamily Helicodiscinae Pilsbry, 1927
The genus Lucilla Lowe, 1852 (syn: Hebetodiscus Baker, 1929 and Hydrophrea Climo, 1974) has not yet been assigned to either of the two subfamilies.
- Greenish disc snail ( Lucilla scintilla (Lowe, 1852))
- White pancake snail ( Lucilla singleyana (Pilsbry, 1889))
literature
- Philippe Bouchet & Jean-Pierre Rocroi: Part 2. Working classification of the Gastropoda . Malacologia, 47: 239-283, Ann Arbor 2005 ISSN 0076-2997
- Michael P. Kerney, RAD Cameron & Jürgen H. Jungbluth: The land snails of Northern and Central Europe. 384 pp., Paul Parey, Hamburg & Berlin 1983 ISBN 3-490-17918-8
- Anatolij A. Schileyko: Treatise on recent terrestrial pulmonate molluscs. Part 8. Punctidae, Helicodiscidae, Discidae, Cystopeltidae, Euconulidae, Trochomorphidae. Ruthenica, Supplement, 2 (8): 1035-1166, Moscow 2002 ISSN 0136-0027
Individual evidence
- ↑ Jürgen H. Jungbluth and Dietrich von Knorre: Trivial names of land and freshwater mollusks in Germany (Gastropoda et Bivalvia). Mollusca, 26 (1): 105-156, Dresden 2008 ISSN 1864-5127 , p. 121.
- ↑ Horace Burrington Baker: Minute Mexican Land Snails. Proceedings of the Academy of Sciences of Philadelphia, 79: 223-246, Philadelphia 1927, pp. 226, 230 (Henry Augustus Pilsbry: as Helicodiscinae)
- ↑ a b MolluscaBase: Helicodiscidae Pilsbry, 1927
- ^ A b Anatolij A. Schileyko: Treatise on recent terrestrial pulmonate molluscs. Part 8. Punctidae, Helicodiscidae, Discidae, Cystopeltidae, Euconulidae, Trochomorphidae. Ruthenica, Supplement, 2 (8): 1035-1166, Moscow 2002 ISSN 0136-0027 , pp. 1051/52
- ↑ Mollbase - subfamily slices worm
- ^ MolluscaBase: Helicodiscus Morse, 1864
- ↑ MolluscaBase: Lucilla RT Lowe, 1852
annotation
- ↑ In the MolluscaBase Hebetodiscus is contradictingly listed on the one hand as a synonym of Lucilla , on the other hand as a subgenus Helicodiscus (Hebetodiscus) as an alternative representation of Helicodiscus or as a synonym of Helicodiscus .