Dunker's amber snail
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Dunker's amber snail ( Oxyloma dunkeri ) |
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| Oxyloma dunkeri | ||||||||||||
| ( L. Pfeiffer , 1865) |
Dunker's amber snail ( Oxyloma dunkeri ) is a species of snail belonging to the family of amber snails (Succineidae) from the suborder of land snails (Stylommatophora).
features
The casing of Oxyloma dunkeri is up to 19 mm high and up to 8.3 mm wide (up to 24 mm high and up to 11.5 mm wide). The last turn is very large, the mouth is 14.5 mm high and 7.3 mm wide. The case is translucent, glossy amber with a thick, solid shell. It usually has three turns. The turns are strongly flattened, the first turn is particularly small. The last handle takes up about two thirds of the height of the case, so the actual thread is very short. It is straight-sided, the lower edge almost straight to slightly concave. The surface shows irregular but clear growth stripes.
The soft body is dark gray to blackish. The sole is three-part and white. In the genital tract, the heart-shaped sex gland is enclosed in a pigmented capsule in the uppermost part of the housing. The initially thin, unpigmented egg ladder emanates from the gland. The egg ladder is very swollen and twisted in the central part. The diameter decreases again and ends in a sack-like structure. The male conductor branches off from this structure and ends in the prostate. The upper part of the fallopian tube is folded tightly in a zigzag fashion. The brown-yellow albumin gland (protein gland) is tongue-shaped and lies on the turns of the egg conductor. The lower part of the fallopian tube is long and opaque. This is where the stalk of the spherical spermathec branches off, which is strongly thickened at the base and about twice as thick as the fallopian tube. The vagina is comparatively wide, about twice as thick as the penis and also comparatively long. It widens to the fallopian tube / stem of the spermathec branch.
In the male tract, the prostate is large and elongated. The spermatic duct is thin and not tortuous. It flows laterally into the penis just before the apex. This is surrounded by a penis sheath. Inside the penis sheath is the actual penis, a strongly twisted epiphallus and a very small, tapered blind sac with a spherical end. The penile retractor muscle attaches to the apex of the penile sheath. It is comparatively thick and long, significantly longer than the penis itself. The penis has "normal" thickness (like Oxyloma elegans and Oxyloma sarsii ) but is only half as wide as the vagina.
Similar species
Dunker's amber snail ( Oxyloma dunkeri ) can usually not be reliably distinguished from the slender amber snail ( Oxyloma elegans ) on the basis of its shell . In the genital apparatus, the penile retractor muscle is significantly longer than the penis (in O. elegans the opposite is true) and the vagina is twice as wide as the penis. The prostate is larger and longer than in Oxyloma elegans . The blind sack at the end of the penis s. st. (in the penis sheath) has a spherical end. In the female part, the branching off of the sperm library is significantly "higher", the vagina is thus significantly longer than in Oxyloma elegans . The stalk of the spermathec is strongly thickened at its base, just after the fallopian tube and stalk branch out. It widens to the fallopian tube / stem of the spermathec branch. In Oxyloma sarsii , the vagina widens towards the atrium. In this species, the stem of the sperm library is also much shorter.
Geographical distribution and habitat
The distribution area of the species extends over Austria, Hungary, Romania, Bulgaria, the Ukraine and southern Russia to Anatolia. An occurrence in South Tyrol is questionable.
The animals live on muddy floors in floodplains.
Taxonomy
The taxon was first described in 1865 by Ludwig Pfeiffer as Succinea dunkeri . The species name is said to honor Wilhelm Dunker .
Succinea hungarica Hazay, 1881 with the two varieties hasta Hazay, 1881 and bipartita Hazay, 1881 is regarded as a synonym by the fauna of Europaea . The species is not recognized by all authors, and was also regarded as a synonym for the slender amber snail ( Oxyloma elegans ).
Danger
Dunker's amber snail is “critically endangered” in Germany (hazard category 2).
literature
- Fechter, Rosina & Gerhard Falkner 1990: Mollusks. 287 pp., Mosaik-Verlag, Munich (Steinbach's Nature Guide 10) ISBN 3-570-03414-3 (p. 166).
- Kerney, Michael P., RAD Cameron & Jürgen H. Jungbluth 1983: The land snails of Northern and Central Europe. 384 pp., Paul Parey, Hamburg & Berlin ISBN 3-490-17918-8 (p. 82).
- Hamilton Ernest Quick: The anatomy of some African Succineae, and of Succinea hungarica Hazay, and S. australis Ferussac for comparison. Annals of the Natal Museum 8: 19-45 1936 (African Journal Archive PDF ).
- 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 .
- Vollrath Wiese: Germany's land snails. 352 pp., Quelle & Meyer, Wiebelsheim 2014 ISBN 978-3-494-01551-4 (p. 47).
Individual evidence
- ↑ Dilian G. Georgiev: Two new species from the family Succineidae (Beck, 1837) (Gastropoda: Pulmonata). Animalia, 41: 7-11, 2006 PDF .
- ↑ a b Julius Hazay: The mollusc fauna of Budapest: with special consideration for the embryonic and biological conditions of their occurrences. 187 p., Cassel, Verlag von Theodor Fischer, 1881 Online at www.biodiversitylibrary.org (p. 14ff.)
- ↑ Atanas Irikov, Zoltán Eröss: An updated and annotated checklist of Bulgarian terrestrial gastropods (Mollusca: Gastropoda). Folia Malacologica, 16 (4): 199-207, Warsaw 2008 PDF .
- ↑ Animal Base: Species summary for Oxyloma dunkeri (Pfeiffer, 1865)
- ↑ Georg Kierdorf-Traut: First addendum to the fauna of the terrestrial shell snails in South Tyrol (Mollusca: Gastropoda). Gredleriana, 6: 277-286, 2006 PDF .
- ↑ Ludwig Georg Karl Pfeiffer: The mollusks of the Dobrudscha. Malakozoologische Blätter, 12: Cassel / Kassel 1865 Online at www.biodiversitylibrary.org (p. 101).
- ↑ Fauna Europaea: Oxyloma (Oxyloma) dunkeri (L. Pfeiffer 1865) .
- ↑ Jungbluth, Jürgen H. & Dietrich von Knorre 2009: Red list of internal mollusks (snails (Gastropoda) and mussels (Bivalvia)) in Germany. 6. Revised and expanded version 2008. Communications of the German Malacoological Society, 81: 1–28, Frankfurt / M. (PDF; 1.3 MB) ( Memento of the original from June 16, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. .
