Perna (genus)
| Perna | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
_2013_001.JPG)
|
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Perna | ||||||||||||
| Philipsson , 1798 |
Perna is agenus of mussels from the family of mussels ( Mytilidae ). The genus has been known since the Eocene (Paleogene).
features
The housings are comparatively large (about 10 to 15 cm, fossil up to 45 cm) with a strongly curved or angled dorsal edge and a straight or slightly convexly curved ventral edge. The shell is relatively thin but firm. The anterior sphincter or the sphincter impression is missing. The posterior sphincter is divided into two bundles and forms a rounded anterior impression and a larger, flat U-shaped posterior impression. 10 to 18 primary teeth are formed during ontogenesis, later they are reduced again. Usually two dysodontic teeth are preserved, rarely just one. The surface or outside of the housing is essentially smooth, only provided with growth strips.
Similar genera
Perna can be distinguished from Mytilus by the pattern of muscle impressions on the inside of the case . In Mytilus , the posterior retractor muscle is a continuous band along the mantle rim; an elongated impression with a U-shaped end towards the rear end, while in Perna the sphincter is divided into two impressions, a rounded front impression and a larger, flat U-shaped rear impression. The anterior sphincter muscle is completely reduced in Perna . This, however, is with Mytilus , albeit z. Sometimes quite small, always available.
Geographical distribution and way of life
The three species of the genus Perna occur in the southern North Atlantic (including the Mediterranean ), the southern South Atlantic, the Indian Ocean (including the Persian Gulf ) and the western Pacific, as well as in New Zealand . A still uncertain fossil find, which can probably be assigned to the genus Perna , was made on Seymour Island in Antarctica .
The three species live in the deeper areas of the intertidal, the subtidal up to about 100 m water depth. In these areas, the water should be rich in plankton and organic matter. The species are therefore also found in brackish estuaries and mangrove forests . They live in the named habitats with byssus attached to rocks, stones, piers, dead shells and even on compact silt and sand.
Taxonomy, systematics and phylogeny
The taxon was drawn up in 1798 by Lorens Münter Philipson . Type species is Perna perna through absolute tautonymy.
- Green-lipped mussel ( Perna canaliculus (Gmelin, 1791)) (New Zealand)
- Perna perna (Linnaeus, 1758) (Atlantic) incl. Perna picta (Born, 1778)
- † Perna rimosa (Lamarck, 1805) ( Lutetium , Eocene)
- † Perna tetleyi (Powell & Bartrum, 1929) ( Altonian , corresponds roughly to Lower Burdigalium , Neogen)
- Perna viridis (Linnaeus, 1758) (Indo-West Pacific, spread on the American east coast since the 1990s)
- Perna sp., Upper Eocene, Seymour Island, Antarctica
According to the molecular genetic analysis by Wood et al. (2006) the genus Perna is monophyletic. Perna perna and the green-lipped mussel are sister taxa, while Perna viridis in turn is the sister taxon of the taxon Perna perna + Perna canaliculus . A fourth recent species of the genus recognized by some authors, Perna picta (Born, 1778), did not differ from Perna perna in terms of molecular genetics and was therefore referred to as the synonym of Perna perna .
literature
- Scott E. Siddall: A clarification of the genus Perna (Mytilidae). Bulletin of Marine Science, 30 (4): 858-870, 1980 PDF .
- Jan M. Vakily: The Biology and Culture of Mussels of the Genus Perna. International Center for Living Aquatic Resources Management, Manila & German Society for Technical Cooperation (GTZ), Eschborn 1989 ISBN 971-1022-70-2 full view on Google Books
- AR Wood, S. Apte, ES MacAvoy, JP Gardner: A molecular phylogeny of the marine mussel genus Perna (Bivalvia: Mytilidae) based on nuclear (ITS1 & 2) and mitochondrial (COI) DNA sequences. In: Molecular phylogenetics and evolution. Volume 44, Number 2, August 2007, pp. 685-698, doi : 10.1016 / j.ympev.2006.12.019 , PMID 17292632 .
Individual evidence
- ↑ Anders Jahan Retzius : Dissertatio historico-naturalis sistens nova testaceorum genera. Quam præside DM Andr. J. Retzio (...) ad publicum examen defert Laurentius Münter Philipsson. 23 p., Lundæ / Lund. (Dissertatio Historico-Naturalis). (Berling) 1788. Online GDZ Göttingen Digitization Center (p. 16)
- ↑ Didier Merle (coord.): Le contenu paléontologique du Lutétien du bassin de Paris. Stratotype Lutétien. 105 p., Muséum national d'Histoire naturelle, Paris & Biotope, Mèze & BRGM, Orléans, 2008 PDF
- ↑ Guido Poppe and Yoshihiro Goto: European Seashells Volume 2 (Scaphopoda, Bivalvia, Cephalopoda) . 221 p., Verlag Christa Hemmen, Wiesbaden 1993 (2000 unc. Reprint), ISBN 3925919104 (p 51)
