Scientists have described two attractive new species of characin from the rivers of Peru and Brazil.
French characin authority Jacques Gery and Axel Zarske described the two new species as Dectobrycon armeniacus and Hyphessobrycon cyanotaenia in a paper written in German in the journal Zoologische Abhandlungen Dresden.
Dectobrycon armeniacus was described only from specimens donated by the German fish wholesaler Aquarium Glaser, which has previously offered the fish for sale under the trade name Pseudochalceus sp. "Apricot Peru".
This attractive, robust-looking and deep bodied tetra, which is believed to reach a size of around 7cm. The fish is predominantly silver-blue with a darker blue longitudinal stripe extending from the operculum to the tail. A preserved specimen of the species has a red belly and back and a thick blank longitudinal stripe extending from the middle of the tail to the operculum.
Gery and Zarske say that the new species can be distinguished from others by the following combination of characters: "five to six teeth in the inner row of the premaxilla; six to 11triscuspid or conical maxillary teeth; dentary teeth not abrubtly decreasing in size; lateral line incomplete; many small scales on basis of caudal, reminiscent of the species of the genus Markiana; four to five supraneuralia; scale formula 7-8/(15-23) 36-38/6-7, (8) iv-v 23-27 (i) anal fin rays and a dark longitudinal band from gill cover to the middle tips of the caudal fin rays".
The second fish, Hyphessobrycon cyanotaenia, is described from Brazil, and has a silver-blue base colour with a darker blue-black longitudinal band running from the operculum to the end of the middle part of the tail.
The species was collected in the Rio Guama in Para state and appears to be a smaller fish with most of the type series measuring only 2-3cm in length.
This species is characterised by the following characters: "short anal fin with 13-15 branched rays; large scales 5/(6-9) 27-30/3-4; two tricuspid maxillary teeth; body relatively high (2.48-3.08 times in standard length); small eye (2.77-3.10 times the head length and a broad blue longitudinal band from the tip of snout to the end of the middle caudal fin rays."
For more details on the new characids see the paper: Zarske A and J Gery (2006) - Beschreibung einer neuen Salmer-Gattung und zweir neuer Arten (Teleostei: Characiformes: Characidae) aus Peru and Brasilien. Zoologische Abhandlungen Dresden. 55: 31-49. (In German).