Rough ham clam
| Rough ham clam | ||||||||||||
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Rough ham clam ( Pinna rudis ) |
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| Scientific name | ||||||||||||
| Pinna rudis | ||||||||||||
| Linnaeus , 1758 |
The rough ham mussel ( Pinna rudis ) is a type of mussel in the family of pen mussels (Pinnidae) from the order of Ostreida .
features
The housing is wedge-shaped in outline and reaches a length of 40 to 50, maximum 56.5 cm. The dorsal margin is usually straight to slightly concave, the anterior margin is concave in the front and convex in the rear. The rear edge is rounded or truncated. The housing field directly on the ventral margin is smooth apart from asymptotic growth strips. There are two sphincters. The anterior sphincter is small, elongated, and sits right in the front tip of the case. The posterior sphincter is elongated parallel to the dorsal edge and sits roughly between the dorsal edge and the midline of the housing. The posterior sphincter sits in the dorsal tongue of the mother-of-pearl layer, the rear end closes with the rear end of the dorsal mother-of-pearl layer. The ventral tongue of the mother-of-pearl layer is only slightly shorter but narrower than the dorsal mother-of-pearl layer. The sulcus between the two tongues of the mother-of-pearl layer is very narrow and almost tapered; but it does not reach the anterior sphincter muscle. The mother-of-pearl layer reaches about a third to two thirds of the total length of the case.
In juvenile specimens, the shell is thin and fragile. In older specimens, the shell thickness increases to 3.5 mm. The surface has five to ten strong radial ribs that intersect with fine comarginal growth strips. The ribs in the rear three quarters of the housing (and initially only dorsally) are covered with very strong, tubular spines open to the rear end, the spines gradually attach to the rear end towards the ventral edge. The largest spines, however, sit on the dorsal margin. Juvenile cases are red-brown or orange-brown, older cases are dark red.
Similar Art
The Schinkel mussel ( Pinna rudis ) is very similar to the Pinna carnea . In this species, however, the ventral tongue of the mother-of-pearl layer is as long as or even longer than the dorsal tongue. The ham clam has five to ten radial ribs with powerful spikes at wide, irregular intervals. Pinna carnea , on the other hand, has eight to twelve fine radial ribs with finer ribs in between; a few small spines may be present on the strong ribs, which are limited to the dorsal part of the housing.
Geographical distribution and habitat
The distribution area of the rough ham clams ( Pinna rudis ) is the Mediterranean and the Black Sea and the adjacent Atlantic. It extends there from Gibraltar along the eastern coast of the Atlantic to Angola . It is also found in the waters around the Canary Islands , the Azores , Ascension and St. Helena . It lives in the depth range of the shallow subtidal, but mostly only from about 20 to about 40, maximum up to 70 meters water depth. In contrast to the noble pen shell , it prefers debris-containing sediments, but it has been found in all possible habitats, from hard substrates to neptune grass - seagrass meadows . It is far rarer in the Mediterranean than Pinna nobilis , for example it was found in only two marine protected areas out of nine examined, while Pnna nobilis was found in all of them. In the examined habitats it also occurs in a low density of individuals. She prefers rather calm water and areas protected from the flow, possibly due to a higher risk of the shells breaking under mechanical stress. In the Archipiélago de Cabrera National Park , where the highest densities so far have been found, it prefers the bottom of the water in submarine caves. When examined, most of the individuals were about 10 to 20 years old, with a maximum of about 30 years.
Species protection
The species is included under the synonymous name Pinna pernula , as a strictly protected species in Appendix II of the Bern Convention on the Conservation of European Wildlife and Their Natural Habitats. This is for the contracting states u. a. the catching, keeping and trade in the species or products thereof are prohibited (Article 6 of the Convention). Protection was adopted into German law through inclusion in Appendix 1 to the Federal Species Protection Ordinance (as a "specially protected" species). In addition, the species is listed as an endangered species according to the Barcelona Convention for the Protection of the Mediterranean from Pollution, according to Appendix II of the Protocol concerning Specially Protected Areas and Biological Diversity in the Mediterranean (SPA / BD Protocol), whereby the contracting states (21 countries bordering the Mediterranean ) have committed themselves to protective measures.
Taxonomy
The taxon was proposed by Carl von Linné in 1758 . It is the type species of the genus Pinna Linné, 1758 by later determination. The MolluscaBase registered the following synonyms : Pinna elongata Röding, 1798, Pinna ferruginea Röding, 1798, Pinna ferruginosa Röding, 1798, Pinna mucronata Poli, 1795, Pinna paulucciae Rochebrune, 1883, Pinna rudis var. Belma de Gregorio, 1885, Pinna rudis var. blama de Gregorio, 1885.
supporting documents
literature
- Peter Schultz, Markus Huber: Revision of the worldwide Recent Pinnidae and some remarks on fossil European Pinnidae. Acta Conchykiorum, 13: 164 S., Hackenheim, ConchBooks, 2013 PDF (summary)
Individual evidence
- ↑ Trigos, S., Vicente, N., García-March, JR, Jiménez, S., Tena, J. and Torres, J .: Presence of Pinna nobilis and Pinna rudis in the Marine Protected Areas of the North Western Mediterranean. Poster, 3rd International Marine Protected Areas Congress 21-27 October 2013 Marseille & Corsica. PDF ( page no longer available , search in web archives ) Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.
- ^ E. Nebot-Colomer, M. Vazquez-Luis, JR Garcia-March, S. Deudero (2016): Population Structure and Growth of the Threatened Pen Shell, Pinna rudis (Linnaeus, 1758) in a Western Mediterranean Marine Protected Area. Mediterranean Marine Science 17 (3): 785-793. doi : 10.12681 / mms.1597
- ↑ Protocol with attachments (English version) PDF (PDF)
- ^ Carl von Linné: Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata. Pp. 1–824, Holmiae / Stockholm, Salvius, 1758. Online at Göttinger Digitization Center (p. 707).
- ↑ a b MolluscaBase: Pinna rudis Linnaeus, 1758
