Notaspidea

from Wikipedia, the free encyclopedia

The division of living beings into systematics is a continuous subject of research. Different systematic classifications exist side by side and one after the other. The taxon treated here has become obsolete due to new research or is not part of the group systematics presented in the German-language Wikipedia.

Pleurobranchaea meckelii , currently superfamily Pleurobranchoidea , family Pleurobranchidae
Tylodina perversa , currently superfamily Umbraculoidea , family Tylodinidae
Umbraculum umbraculum , currently superfamily Umbraculoidea , family Umbraculidae

In the subordination Notaspidea (Greek νῶτον: back, άσπις: plate) or Pleurobranchacea (πλευρά: side edge βράγχια: gills), German Flankenkiemer or Seitenkiemer , even back plate screw , a heterogeneous group of opisthobranch , both the housing carrying snails were combined and slugs . The feature that gives the German name its name is an external right gill. The taxon is omitted in the system of Bouchet & Rocroi (2005).

features

anatomy

Characteristics of the flank gills are an external feather gill ( ctenids ) on the right side, a flat shell and rolled up rhinophores . The snails of the families Tylodinidae and Umbraculidae , which outwardly resemble the unrelated limpets and are therefore also called "false nudibranchs", have large outer shells and a small coat . In the Pleurobranchidae family , the situation is reversed : They have a clearly visible coat and an inner shell. The shell is a product of evolutionary regression and can even be completely absent in the adult stage.

nutrition

Adult flank gills are carnivores or scavengers.

Protection mechanisms

Many species produce toxic skin secretions for self-defense.

Systematics

The taxon Notaspidea was established in 1883 by the French zoologist Paul Henri Fischer , who combined the two families Pleurobranchidae Menke, 1828 (sea slugs with outer pinnate gills on the right) and Tylodinidae Gray, 1847 (sea snails with limpets with a pinnate shell and outer gills on the right). This group was also adopted by Johannes Thiele (1929–1935) in his taxonomy of snails, which was recognized until the 1990s. The group's monophyly was questioned by Luise Schmekel in 1985 and has since been rejected by several other authors. The characteristic feature, the feather gill on the right side of the body, was now regarded as a plesiomorphism and the taxon as a paraphyletic group. However, the Notaspidea still appear in the systematics of Ponder & Lindberg (1997), in which they include the families Pleurobranchidae Menke, 1828, Tylodinidae Gray, 1847 and Umbraculidae Dall , 1889. Bouchet & Rocroi (2005) reject the group in the currently accepted systematics of snails , which is based on molecular genetic studies, and place the two previously combined groups in different taxa within the hind gill. The Umbraculoidea, which include the Umbraculidae and Tylodinidae, are hereafter a sister group of the Cephalaspidea , with which they belong to the Euopisthobranchia , while the Pleurobranchidae with the nudibranchs , their sister group, form the Nudipleura .

Current systematics according to Bouchet & Rocroi (2005)

In the systematics of Bouchet & Rocroi (2005) the taxon Notaspidea was taken out of service.

The families of the Notaspidea merged into the new claden Nudipleura (H. Wägele & R. C. Willan, 2000), Umbraculida (W. H. Dall, 1889) and the new superfamilies Pleurobranchoidea (J. E. Gray, 1827), Umbraculoidea (W. H. Dall, 1889). The superfamilies were introduced for the sake of consistency and attributed to the discoverers of the families that gave them their names.

Old system according to Ponder & Lindberg (1997)

literature

Individual evidence

  1. ↑ Harry Erhardt, Horst Moosleitner: Mergus Sea Water Atlas - Volume 2 . Mergus Verlag, Melle 1997. Notaspidea - Back shield snails : p. 646.
  2. ↑ a b P. Bouchet et al. a .: Part 2. Working classification of the Gastropoda. In: Malacologia. 47, No. 1-2, 2005, pp. 239-283
  3. ^ RC Willan: Phylogenetic systematics of the Notaspidea (Opisthobranchia) with a reappraisal of families and genera . In: American Malacological Bulletin . tape 5 , 1987, pp. 215-241 .
  4. ↑ Aldo Spinella, Ernesto Mollo, Enrico Trivellone, Guido Cimino: Testudinariol A and B, two unusual triterpenoids from the skin and the mucus of the marine mollusc Pleurobrancus testudinarius . In: Tetrahedron . tape 53 , no. 49 , 1997, pp. 16891-16896 , doi : 10.1016 / S0040-4020 (97) 10124-7 .
  5. ^ Johannes Thiele: Handbook of systematic molluscology. Fischer, Jena 1931–1935 (two volumes).
  6. ^ Luise Schmekel: Aspects of Evolution within the opisthobranchs . In: R. Trueman, MR Clarke (Eds.): The Mollusca. Vol. 10. Evolution . Academic Press, New York 1985. pp. 221-267.
  7. ^ A b Winston F. Ponder , David R. Lindberg : Towards a phylogeny of gastropod molluscs: an analysis using morphological characters. In: Zoological Journal of the Linnean Society. 119, No. 2, 1997, pp. 83-265, doi : 10.1111 / j.1096-3642.1997.tb00137.x .
  8. ↑ Cristina Grandea, Josè Templadoa, J. Lucas Cerverab, Rafael Zardoya: Phylogenetic relationships among Opisthobranchia (Mollusca: Gastropoda) based on mitochondrial cox 1, trnV, and rrnL genes . In: Molecular Phylogenetics and Evolution . tape 33 , no. 2 , p. 378-388 , doi : 10.1016 / j.ympev.2004.06.008 .
  9. ^ A b Philippe Bouchet, Jean-Pierre Rocroi: Classification and Nomenclator of Gastropod Families. ConchBooks, Hackenheim 2005, ISBN 3-925919-72-4 .
  10. ↑ Guido T. Poppe, Sheila P. Tagaro: The New Classification of Gastropods according to Bouchet & Rocroi, 2005. ( Memento of the original from September 27, 2007 in the Internet Archive ) Info: The @1@ 2Template: Webachiv / IABot / www.journal-malaco.fr 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. (PDF; 195 kB) 2006.

Web links

  • Notaspidea at ITIS (English, still with the old system according to Ponder & Lindberg)