Eight-armed squids
| Vampyropoda | ||||||||||||
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Vampyroteuthis infernalis , drawing by Carl Chun |
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| Scientific name | ||||||||||||
| Vampyropoda | ||||||||||||
| Boletzky , 1992 | ||||||||||||
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The group of eight-armed cuttlefish (Octopodiformes or Vampyropoda) includes the octopus in the narrower sense (Octopoda), the cirrus octopus (Cirroctopoda) and the vampire squid- like (Vampyromorpha).
You are distinguished by having eight poor. The vampire squid-like have a pair of retractable filaments between the first two pairs of arms (counting from the head), which are used as sensory organs.
The early development in the egg of the eight-armed squid and the intermediate position of the vampire squid-like ones prove that the group originally descended from ten-armed squids . The oldest representatives of the eight-armed squid are known from the Carboniferous . However, this find is controversial. Safe representatives of the group are known from the Rhaetium of the Upper Triassic .
Systematics
The system covers four subgroups, which in turn are divided into several families and hundreds of species and subspecies.
- Cirrina (cirrus octopus)
- Octopoda (Kraken)
- Trachyteuthididae †
- Vampyromorpha (vampire squid-like)
literature
- Thomas Berthold and Theo Engeser: Phylogenetic analysis and systematization of the Cephalopoda (Mollusca). Negotiations of the Natural Science Association Hamburg. NF, 29, Hamburg 1987, ISSN 0173-749X . Pp. 187-220.
- David B. Carlini, Richard E. Young and Michael Vecchione: A molecular phylogeny of the Octopoda (Mollusca: Cephalopoda) evaluated in light of morphological evidence. In: Molecular Phylogenetics and Evolution. 21 (3), San Diego 2001 ISSN 1055-7903 , pp. 388-397.
- Richard E. Young and Michael Vecchione: Evolution of the gills in the Octopodiformes. In: Bulletin of Marine Science. 71 (2), Coral Gables, Florida 2002, ISSN 0007-4977 , pp. 1003-1017.
