Ox heart (shell)
| Ox heart | ||||||||||||
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Ox heart ( Glossus humanus ), front view of the case |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Glossus | ||||||||||||
| Poli , 1797 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Glossus humanus | ||||||||||||
| ( Linnaeus , 1758) |
The ox heart ( Glossus humanus ) is a type of mussel from the tongue clam family (Glossidae). It is the only recent species and type of the genus Glossus .
features
The ox heart is characterized by the large, strongly rolled-up vertebrae and the spherical housing. It has the same key, but the keys are strongly asymmetrical. It can reach a case width of up to 160 mm, but this is rarely the case. Most cases are between 60 and 80 mm in size. The shell is relatively thin, but firm. The housing color varies from beige to dark brown. The vortices are usually lighter than the rest of the case. The lock is relatively wide with very long main teeth on both flaps that extend parallel to the lock axis. The anterior lateral teeth, on the other hand, are greatly reduced or absent entirely, while the posterior lateral teeth are greatly elongated. The two sphincters are irregular; the front muscle is slightly smaller. The animals are of separate sex; the gonads mature in August to September and the sex products are released into the open water from September. A trochophora larva develops from the fertilized eggs .
Way of life, occurrence and distribution
The distribution area of this species is the eastern Atlantic from Iceland to Morocco. It also penetrates the Mediterranean and the English Channel (smaller individuals). It can often be found in the Bay of Biscay and the Adriatic Sea . It also occurs in the Azores . It lives half-buried in calm water on sandy to muddy bottoms. The vertical distribution ranges from about 7 to 250 m. The water depth of 8 to 3000 m given by Tucker and Dance is probably based on an error. The main distribution, however, is in somewhat deeper, calm water (from around 50 m). It feeds on plankton and other microscopic particles, which it filters out of the water with its gills. The siphons are quite short due to the low burial depth. The foot is relatively poorly developed in relation to the size of the animal, but it can stretch a lot. Older specimens hardly use the foot anymore. The byssus gland is well developed on the foot, but byssus threads are only produced by younger specimens.
Related species
Glossus humanus is the only recent species in the genus Glossus . The species was the father of modern taxonomy, Carl Linnaeus, the Cardium humanum described . Some other species that were previously assigned to this genus are now included in the related genus Meiocardia .
Subspecies
It is noticeable that specimens of the Glossus humanus from the North Atlantic are smaller than the Mediterranean representatives of the species and the shell appears somewhat more elongated. Therefore, the British malacologist Lovell Augustus Reeve (1814-1865) introduced the scientific name Glossus humanus hibernicus (Reeve, 1845) for this form of the Glossus humanus in 1845. The elongated shape is likely due to different diets and living conditions.
Individual evidence
- ↑ Owen, p. 92
- ^ MolluscaBase: Glossus Poli, 1795
literature
- Gareth Owen: On the biology of Glossus humanus (L.) ( Isocardia cor Lam.). Journal of the Marine Biological Association of the United Kingdom, 32 (1): 85-106, Plymouth ISSN 0025-3154 PDF
- Guido Poppe and Yoshihiro Goto: European Seashells Volume 2 (Scaphopoda, Bivalvia, Cephalopoda) . 221 pp., Verlag Christa Hemmen, Wiesbaden 1993 (2000 unc. Reprint) ISBN 3-925919-10-4
- R. Tucker Abbott and S. Peter Dance: Compendium of Seashells. 411 pp. Odyssey Publishing, El Cajon, California ISBN 0-9661720-0-0