State jellyfish
State jellyfish | ||||||||||||
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Portuguese galley ( Physalia physalis ) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Siphonophorae | ||||||||||||
Eschscholtz , 1829 |
The state jellyfish (Siphonophorae) are an order of stick-forming and free-swimming cnidarians of the class of hydrozoans , whose sticks each consist of hundreds to thousands of polyps .
features
The individual animals of the hive are so highly specialized and diverse that they can almost be viewed as organs of a single organism . There are feeding polyps (gastro- / autozooids), tactile polyps, defense polyps (dactylozooids), sexual polyps (gonozooids) and cover polyps (phyllozooids) as well as the upper floating buoy (pneumatophore) and numerous swimming bells (nectophores). The most famous state jellyfish is the Portuguese galley ( Physalia physalis ). The tentacles of individual species can be up to 50 meters long.
Catching prey
In 2005 US researchers caught some specimens of a new species of the genus Erenna ( Erenna sp. Nov. ) From a depth of 1,600 to 2,600 m and found that newly formed tentacles emitted blue-green, fully grown tentacles but red light. The researchers suspected that, contrary to previous assumptions, the jellyfish with this red light in the deep sea attract seldom found fish as food sacrifices. Since, on the one hand, state jellyfish feed primarily on fish and two of the caught specimens just digested one, but on the other hand the probability of such an accidental food finding of the jellyfish at this depth is very low, this would mean that such fish definitely perceive the red light and be attracted by it successfully.
Systematics
The systematics of the Siphonophorae reproduced here follows the information in the Hydrozoa Directory .
- Suborder Physonectae
- Family Agalmatidae
- Family Apolemiidae
- Family Athorybiidae
- Family Erennidae
- Genus Erenna
- Family Forskaliidae
- Family Physophoridae
- Family Pyrostephidae
- Family Rhodaliidae
- Physonectae incertae sedis
- Suborder Calycophorae
- Family Abylidae
- Family Clausophyidae
- Family Diphyidae
- Family Hippopodiidae
- Family Prayidae
- Family Sphaeronectidae
- Suborder Cystonectae
- Family Physaliidae
- Family Rhizophysidae
Haeckel's State Jellyfish Pictures
Ernst Haeckel described numerous state jellyfish, and some panels in his work Kunstformen der Natur (1904) show artistic pictures of some species .
See also
Web links
- siphonophores.org Extensive website about siphonophores (English)
- Information on the structure at lifesci.ucsb.edu (English)
Individual evidence
- ↑ DER SPIEGEL: Mallorca: Portuguese galleys are so dangerous - DER SPIEGEL - science. Retrieved April 18, 2020 .
- ↑ Science : Bioluminescent and Red-Fluorescent Lures in a Deep-Sea Siphonophore (Abstract) , published July 8, 2005, accessed October 5, 2017.
- ↑ Peter Schuchert, The Hydrozoa Directory (accessed October 1, 2007)