Trentino glass snail
| Trentino glass snail | ||||||||||||
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Trentino glass snail ( Vitrinobrachium tridentinum ) |
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| Scientific name | ||||||||||||
| Vitrinobrachium tridentinum | ||||||||||||
| Forcart , 1956 |
The Trentino glass snail ( Vitrinobrachium tridentinum ) is a "half-nudibranch" from the family of glass snails (Vitrinidae), which belongs to the land snails (Stylommatophora). The animals can no longer completely withdraw into the small housing.
features
The right-hand wound housing is very flat and conical with a very crooked mouth, so that the housing can also be described as an ear-shaped in the overall habitus. It becomes 5.5 to 6 mm wide and 2.7 mm high. It has 2 to 2.15 turns, the first turns are wound very tightly and the last turn grows very quickly. The end turn takes up about 60% of the total diameter at the mouth. The turns are very slightly arched on the top, the seam is very flat. The mouth measures 4.3 mm in width and 3.1 mm in height. The mouth edge is straight and sharpened. There is no skin seam on the lower edge of the mouth and spindle. There is also no navel.
The shell is thin and fragile. It is light brown in color and translucent. The surface is smooth and shiny except for faint growth lines. The embryonic housing has densely standing small pits arranged in spiral lines.
The soft body is light gray, the neck can be colored more or less intensely brownish-red. The dark gray coat covers almost the entire front part of the body and also reaches almost down to the sole on the sides. The animal is stretched to about 16 mm long. In the hermaphroditic genitalia, the spermatic duct (vas deferens) is quite short. It penetrates the penis subapically. The penile retractor muscle also attaches subapically. The penis is structured in an anvil-like distal part (with the insertion of the spermatic duct and penile retractor) and a longer proximal part. The spermathec attaches to the proximal part of the penis, near the constriction to the distal part. This has a short, thick stem and a small, rounded bladder. The penis joins the free fallopian tube and the sarcobelum into the long atrium. In the female part, the free introducer (oviduct) is moderately long, a vagina is missing, opposite the confluence of the penis into the atrium there is a blind sac-like enlargement, the copulation arm or sarcobelum. the copulation arm is everted during copulation and is quite mobile. The sarcobelum contains a conical structure that ends at the top in a spherical glandular head, which is closed to the atrium with a papilla that is designed as a suction cup towards the atrium.
Similar species
The shell of the Tridentine glass snail differs only slightly from the short glass snail ( Vitrinobrachium breve ). The inner turns of the Tridentine glass snail are a little more tightly wound, the end turn increases more quickly and is a little wider. There are a little more turns and the case apex is flatter. The main difference, however, is in the genital apparatus; the spermathec is attached to the distal part of the penis, not the atrium, as in the short glass snail.
Geographical distribution and habitat
The distribution area is also limited to a small area in the Italian southern Alps (provinces of Bozen , Brescia , Trient and Vicenza ) between 200 and 1500 m above sea level (in Kerney et al., 1983 erroneously only in Switzerland ). The information given by the IUCN (southern Switzerland) probably also refers to this erroneous information. Nardi (2015) only gives localities in the Italian Southern Alps.
The animals live in moist montane deciduous forests under the leaf litter or under stones.
Taxonomy
The taxon was proposed by Lothar Forcart in 1956. It's widely accepted.
Danger
According to the IUCN, there is not enough data (data deficient) to be able to assess the endangerment situation of the species.
literature
- Rosina Fechter and Gerhard Falkner: molluscs. 287 pp., Munich, Mosaik-Verlag 1990 (Steinbach's Nature Guide 10) ISBN 3-570-03414-3 , p. 172
Individual evidence
- ^ A b Gianbattista Nardi, Ivano Niero, Antonio Braccia: Nota sui Vitrinidae (Gastropoda, Pulmonata). Natura Bresciana, 35: 101-119, 2007 PDF (ResearchGate)
- ↑ a b c Gianbattista Nardi: Gli endemiti della fauna malacologica bresciana. Natura Bresciana, 39: 57-93, 2015 PDF (ResearchGate)
- ↑ a b Lothar Forcart: The Vitrinidae of the Eastern Alps. Archiv für Molluskenkunde, 85 (1-3): 1-14, 1956, pp. 6/7.
- ^ A b Francisco W. Welter-Schultes: European non-marine molluscs, a guide for species identification = identification book for European land and freshwater mollusks. A1-A3 S., 679 S., Q1-Q78 S., Planet Poster Ed., Göttingen 2012, ISBN 3-933922-75-5 , ISBN 978-3-933922-75-5 (p. 430)
- ↑ a b The IUCN Red List of Threatened Species: Vitrinobrachium tridentinum
- ↑ AnimalBase: Vitrinobrachium tridentinum (Forcart, 1956)
- ↑ Fauna Europaea: Vitrinobrachium tridentinum (Forcart, 1956)
- ↑ Michael P. Kerney, RAD Cameron & Jürgen H. Jungbluth: The land snails of Northern and Central Europe. 384 pp., Paul Parey, Hamburg, p. 151.
- ↑ MolluscaBase: Vitrinobrachium tridentinum (Forcart, 1956)