Meganeura

from Wikipedia, the free encyclopedia
Meganeura
Meganeura, schematic reconstruction drawing

Meganeura , schematic reconstruction drawing

Temporal occurrence
Upper carbon
approx. 300 million years
Locations
Systematics
Arthropod (arthropoda)
Insects (Insecta)
Flying insects (Pterygota)
Meganisoptera
Meganeura
Scientific name
Meganeura
Brongniart , 1885

Meganeura is an extinct genus of insects. They lived around 300 million years ago at the end of the Carboniferous , were very similar to today's dragonflies, and reached a wingspan of up to 70 cm . They are placed in the unspecific group of the Meganisoptera (ex Protodonata, "giant dragonflies").

species

Meganeura monyi was found in the Stephan coal seams of Commentry , Allier department in France in the 1880s. She lived in the Upper Carboniferous and was described in 1885 by the French paleontologist Charles Brongniart . Today the specimen of this species is kept in the Muséum national d'histoire naturelle in Paris. With a wingspan of, depending on the reconstruction, 66 to 70 centimeters and a trunk diameter of around 2.8 centimeters, it was one of the largest insects that ever lived.

Original fossil of an unknown species of the Meganeuridae

The best preserved specimen, later declared a type specimen , shows an incomplete impression of the body with all four wings without their outer (distal) sections. Large parts - such as the rear part of the abdomen - have not been preserved. Images of the fossil can be found in Nel et al. The exact size of the animal is based on reconstructions. The prominent and well-known species has been reconstructed several times, after it was first described by Anton Handlirsch and Robin John Tillyard, among others . The species has a relatively small body for its wingspan, which is relatively smaller than that of the recent large dragonflies. The wing veins have numerous primeval features (plesiomorphies) compared to the recent large dragonflies: there is no wing mark (pterostigma), nodus or wing triangle. The longitudinal veins are predominantly relatively delicate and mostly parallel, heaped close together in the front wing section. The branches of the cubitus are s-shaped. The species can be distinguished from other primeval dragonflies of the same time (of the order Meganisoptera) in the details of the wing veins. The legs had five tarsal segments .

Meganeura monyi is only known from the type locality and was never found again after the original finds. For a long time it was considered the only species of the genus to which only a few poorly preserved fossils from the Urals and Canada were assigned, which, however, most likely do not belong. The affiliation of some wing fragments from Commentry itself to the species has also been questioned by others. The species was assigned by Handlirsch as a type species of a family Meganeuridae , in which many paleontologists have followed him. However, according to recent finds of related species, the characteristics used to delimit the family are unclear, so that the exact relationships are doubtful.

literature

  • Anton Handlirsch: The fossil insects and the phylogeny of recent forms; a manual for paleontologists and zoologists. W. Engelmann, Leipzig 1908, pp. 307-309.

media

  • Les Mondes Perdus. Part: Qui a tué les insectes géants? (Erased: Who killed the fat bums?). Documentation; Direction: Emma Baus, Bertrand Loyer; Saint-Thomas Productions; F 2015; Arte, Aventure Humaine (discovery) , December 2016 ( Weblink , arte.tv ) - with numerous modern computer animations.

Web links

Commons : Meganeura  - collection of images, videos and audio files

Individual evidence

  1. ↑ A specimen with a wingspan of 72 cm was found from another closely related giant dragonfly, Meganeuropsis permiana .
  2. ^ A b André Nel, Günther Fleck, Romain Garrouste, Georges Gand, Jean Lapeyrie, Seth M. Bybee, Jakub Prokop: Revision of Permo-Carboniferous griffenflies (Insecta: Odonatoptera: Meganisoptera) based upon new species and redescription of selected poorly known taxa from Eurasia. In: Palaeontographica Department A 289, Delivery 4–6 (2009), pp. 89–121.
  3. ^ André Nel, Günter Bechly, Jakub Prokop, Olivier Béthoux, Gunther Fleck: Systematics and Evolution of Paleozoic And Mesozoic Damselfly-Like Odonatoptera of the 'Protozygopteran' Grade. In: Journal of Paleontology 86 (1) (2012), pp. 81-104. doi : 10.1666 / 11-020.1
  4. ↑ Yongjun Li, Olivier Bethoux, Hong Pang, Dong Ren: Early Pennsylvanian Odonatoptera from the Xiaheyan locality (Ningxia, China): new material, taxa, and perspectives. In: Fossil Record 16 (1) (2013), pp. 117-139. doi : 10.1002 / mmng.201300006