Ornamental tetra
| Ornamental tetra | ||||||||||||
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Common tetra ( Hyphessobrycon rosaceus ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Hyphessobrycon rosaceus | ||||||||||||
| Durbin , 1909 |
The silver tetra ( Hyphessobrycon rosaceus ), also known as the rose tetra , is a small tetra species that is widespread in the northeast of South America in the areas of the Essequibo , Corantijn and Suriname rivers.
features
The jewel tetra reaches a length of 3.5 to 4 cm and has a moderately high, laterally strongly flattened body with a back line that is more curved than the belly line. The greatest body height is just before the beginning of the dorsal fin. Due to the rosy basic color, a slightly higher back body, larger eyes and the white color of the first fin rays and fin tips of the anal fin and pelvic fins, the species can be easily distinguished from the olive-brown species Hyphessobrycon bentosi , with which it was often confused in the past. There is no shoulder mark. The scales on the back have a dark border. The first rays of the dorsal and anal fin are orange, the tips of the second and third rays of the dorsal fin are white. There is a black spot on the extended tip of the dorsal fin. The caudal fin is deeply forked. An adipose fin is present. The maxillary of Hyphessobrycon bentosi is occupied by 4 to 6 conical teeth, the number of teeth increasing with age.
- Fin formula : dorsal 11, anal 26-27.
- Flake formula : mLR 31-33, SL 6-7.
Systematics and taxonomy
Hyphessobrycon rosaceus was first described scientifically in 1909 by the American ichthyologist Marion Durbin Ellis (1887–1972). From the beginning the species was assigned to the genus Hyphessobrycon , which differs from Hemigrammus only in the unscaled caudal fin base . Within the genus Hyphessobrycon , H. rosaceus belongs to the Rosy tetra species group . In specialist aquarium literature, Hyphessobrycon rosaceus has been constantly confused with other species from the Rosy Tetra species group, particularly often with Hyphessobrycon bentosi and Hyphessobrycon jackrobertsi (known as Hyphessobrycon 'robertsi' between 1958 and 2014 ). H. rosaceus was listed as a subspecies of H. bentosi for a while. To end the confusion, Axel Zarske, then head of the ichthyology section of the Senckenberg Natural History Collections in Dresden , published a new description of Hyphessobrycon bentosi and an initial description of Hyphessobrycon 'robertsi' under the name Hyphessobrycon jackrobertsi in 2014 . He identified the tetra, which is called H. bentosi in most aquarium books , as H. rosaceus .
Individual evidence
- ↑ Hyphessobrycon rosaceus in the IUCN Red List of Threatened Species 2013.2. Posted by: Reis, R & Lima, F., 2007. Retrieved July 18, 2019.
- ↑ a b Hyphessobrycon rosaceus on Fishbase.org (English)
- ↑ a b c d e Günther Sterba : Freshwater fish of the world. 2nd Edition. Urania, Leipzig / Jena / Berlin 1990, ISBN 3-332-00109-4 . Page 101.
- ^ A b c Axel Zarske (2014): On the system of some blood tetra or Rosy tetras (Teleostei: Ostariophysi: Characidae). Vertebrate Zoology 64 (2): 139-167. PDF
- ↑ Tropical fish hobbyist: 7 (2): 76, 1958