Mortillet's gloss snail

from Wikipedia, the free encyclopedia
Mortillet's gloss snail
Mortillet's gloss snail (Oxychilus mortilleti)

Mortillet's gloss snail ( Oxychilus mortilleti )

Systematics
Order : Lung snails (pulmonata)
Subordination : Land snails (Stylommatophora)
Superfamily : Gastrodontoidea
Family : Gloss snails (Oxychilidae)
Genre : Oxychilus
Type : Mortillet's gloss snail
Scientific name
Oxychilus mortilleti
( L. Pfeiffer , 1859)

Mortillets gloss snail ( Oxychilus mortilleti ), also called mountain gloss snail, is a land snail from the family of gloss snails (Oxychilidae); this family belongs to the subordination of land snails (Stylommatophora). The individuals of an isolated occurrence in the Franconian Alb are excreted as a subspecies ( Kelheim gloss snail , Oxychilus mortilleti planus ).

features

The right-hand wound housing is flattened-conical to almost flat. It measures 11 to 15 mm in diameter, exceptionally also up to 17 mm, and 4 to 7 mm in height. In the adult stage it has 5 to 6.5 turns, which increase relatively uniformly up to the last turn. They are only slightly arched at the top. The seam is relatively deep. The last turn increases in width a little faster, it is 1.5 to twice as wide as the penultimate turn. the periphery is thereby also more rounded. The last quarter of the end turn also descends slightly from the turn axis of the housing. When viewed directly from above, the mouth is flattened-elliptical to ovoid (apart from the incision through the previous turn). The mouth edge is straight and sharp. The navel is deep and cylindrical. It takes about 1/6 to 1/7 of the diameter.

The color of the shell varies from horn-colored to reddish brown. It's translucent. There are fine streaks of growth on the surface, which often look a bit wrinkled. There are also fine spiral stripes, but these are only visible with a magnifying glass and especially at the seam. The surface is still smooth and glossy.

The soft body is colored blue-black. In contrast, the sole of the foot is more whitish. The radula has 29 to 31 elements per transverse row. In the hermaphroditic genital apparatus, the spermatic duct (vas deferens) is quite short. It penetrates the epiphallus apically. This initial part is initially thickened; it becomes thinner again by the time it enters the penis. Shortly before entering the epiphallus, the spermatic duct is connected to the penis by a few strands of tissue. The epiphallus penetrates the penis below the apex. The apex is formed by a blind sac (caecum, or often also called glagellum). The penile retractor muscle attaches to the apex of this blind sac of the penis. The penis is clearly divided into a proximal and distal part, which are connected by a "bottle neck". The proximal part of the penis has 6 to 13 rows of very small, numerous, polygonal or pyramidal papillae inside. However, they are not connected to each other and do not form wavy folds. The distal part of the penis only has longitudinal folds on the inside. It is surrounded by a muscular tissue cover, but it can also be a little shorter than the distal part of the penis. The proximal part is longer than the distal part of the penis. The distal part is connected to the atrium through a thin opening. In the female part of the genital system, the free fallopian tube is quite short and the vagina twice as long. The perivaginal gland encloses the upper part of the vagina, the lower part of the free fallopian tube and the stem of the spermathec. The stem of the spermathec is quite long, the bladder pear-shaped. It almost reaches the albumin gland. The vagina and penis open into a very short atrium.

Similar species

Mortillet's gloss snail is similar to the cellar gloss snail ( Oxychilus cellarius ). However, the last turn is a little wider and the mouth is better rounded and a little bigger. The shell of Mortillet's gloss snail is more tightly wound with a deeper seam. The case is also a bit larger and darker on average. A reliable distinction between the two types is only possible on the basis of the anatomy. The penis, spermatic duct ( vas deferens ) and the stem of the spermathek are longer and relatively narrower than that of the cellar snail and the large glossy snail ( Oxychilus draparnaudi ). In the latter type, the navel is slightly wider. The navel of the smooth gloss snail ( Morlina glabra ) is somewhat narrower.

Distribution area of ​​the species (according to Welter-Schultes)

Geographical distribution and habitat

The species occurs mainly in the southern Alps, northern Italy and Istria . There are only a few known occurrences north of the Alps in Bavaria ( Allgäu and Berchtesgaden Alps , Altmühltal ), in Austria and in the Czech Republic .

The animals live under moss-grown stones, rubble and leaves, on old walls, vineyard terraces and crevices, in damp, shady places. They occur in open and semi-open areas, but also in forests. They prefer higher altitudes, in Switzerland the species has been recorded up to 1,600 m above sea level. You are not limited to calcareous soils

Way of life and reproduction

Mortillet's gloss snail eats withered plant material, but is mainly a carnivore . With only plant food, the animals take care and hardly grow. They need animal nutrition for normal development. It bites the prey, mostly smaller slugs and slugs, and paralyzes them with a poison. The prey is then eaten up quickly.

The eggs are laid under moss from March to May. A clutch contains only two to five relatively large eggs. These are milky, round and 1.4 mm in diameter. The animals are sexually mature at eleven to twelve months, but the housing continues to grow a little. In captivity, the animals reached a maximum age of 6 years.

Taxonomy

The taxon was first described in 1859 by Ludwig Karl Georg Pfeiffer in the original combination Helix Mortilleti . However, he attributed the taxon to Josef Stabile . The name was apparently communicated to him by letter from Josef Stabile. However, it is not apparent that Stabile contributed to the description, so that the name must be attributed to Ludwig Pfeiffer. Some authors have interpreted the name as a replacement name ( nomen novum ) for Helix villae Pfeiffer, 1856, which was already assigned by Helix villae Deshayes, 1850. However, there is no indication in the text that he wanted to replace this preoccupied name, so that Helix mortilleti is to be interpreted as a new scientific name. The name is widely recognized.

The genus Oxychilus is divided by some authors into sub-genera. In this classification, Mortillet's gloss snail is included in the nominate subgenus Oxychilus (Oxychilus) Fitzinger, 1833. Currently the species is divided into two subspecies:

  • Oxychilus mortilleti mortilleti (Pfeiffer, 1859), the nominate subspecies, thread still slightly raised, in the greater part of the distribution area
  • Oxychilus mortilleti planus (Clessin, 1877) (Kelheim gloss snail), the upper side is almost completely flat, only in the Franconian Jura near Kelheim.

Danger

The subspecies Oxychilus mortilleti planus or Kelheim's gloss snail, which lives in Bavaria, is on Bavaria's Red List of Endangered Mussels and Snails. According to Vollrath Wiese, it is extremely rare. It is considered endangered in Switzerland. In Austria, the species is potentially endangered in almost all federal states . The IUCN has assessed the species as not endangered across its entire range.

literature

  • Klaus Bogon: Land snails biology, ecology, biotope protection. 404 p., Natur Verlag, Augsburg 1990, ISBN 3-89440-002-1 , p. 208/09.
  • 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 , p. 171.

Individual evidence

  1. ↑ Jürgen H. Jungbluth, Dietrich von Knorre: Trivial names of land and fresh water mollusks in Germany (Gastropoda et Bivalvia). Mollusca, 26 (1): 105-156, Dresden 2008 ISSN  1864-5127 , p. 122.
  2. ^ Rosina Fechter and Gerhard Falkner: Molluscs. 287 p., Mosaik-Verlag, Munich 1990 (Steinbach's Nature Guide 10) ISBN 3-570-03414-3 , p. 180.
  3. ↑ a b c 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., Göttingen, Planet Poster Ed., 2012 ISBN 3-933922-75-5 , ISBN 978-3-933922-75-5 (S. 387)
  4. ^ Ewald Frömming: Biology of the Central European Landgastropods. 404 S., Duncker & Humblot, Berlin, 1954, pp. 100-103.
  5. ^ Ludwig Karl Georg Pfeiffer: Monographia heliceorum viventium. Sistens descriptiones systematicas et criticas omnium huius familiae generum et specierum hodie cognitarum. Volume quarter. S. I-IX (= 1-9), 1-920. Brockhaus, Lipsiae / Leipzig, 1859 Online at Biodiversity Heritage Library , p. 101.
  6. ↑ Giuseppe Manganelli, Falco Giust: Oxychilus mortilleti (Pfeiffer, 1859): a Redescription (Pulmonata: Zonitidae). Basteria, 61: 123-143, 1998.
  7. ↑ a b AnimalBase: Oxychilus mortilleti (Pfeiffer, 1859)
  8. ↑ a b Fauna Europaea: Oxychilus (Oxychilus) mortilleti (L. Pfeiffer, 1859)
  9. ↑ MolluscaBase: Oxychilus mortilleti (L. Pfeiffer, 1859)
  10. ↑ a b Vollrath Wiese: The land snails of Germany. 352 pp., Quelle & Meyer, Wiebelsheim 2014, ISBN 978-3-494-01551-4 (p. 187)
  11. ↑ Bavaria's Red List of Endangered Mussels and Snails PDF
  12. ↑ Christina Frank, Peter L. Reischütz: Red List of Endangered Mollusks Austria (Mollusca: Gastropoda and Bivalvia). Green series of the Ministry of Life, 2, 283-316, Vienna 1994. PDF
  13. ↑ The IUCN Red List of Threatened Species: Oxychilus mortilleti