| Characidae (Characins; tetras), subfamily: Stevardiinae |
| 4 cm SL (male/unsexed) |
|
benthopelagic; freshwater |
| South America: Rio Xingu basin in Brazil. |
|
Dorsal soft rays (total): 10-10; Anal soft rays: 22-27; Vertebrae: 37-39. Phallobrycon and Bryconadenos are the only members of the Clade A characids that possess a combination of intumescent glandular tissue present on the anterior part of the anal fin and pelvic-fin hooks absent in sexually mature males. This species can be diagnosed by the following characters: the glandular tissue is associated with specially developed spines on some anal-fin rays. Two developed spines are present on median unbranched portions of fifth, sixth and seventh anal-fin rays which are larger and separated from the close-set smaller hooks that appear on distal portions of the anterior anal-fin rays of Phallobrycon, and different from those found on distal portions of several anal-fin rays of many characids. Large spines and small hooks are never found together on any anal-fin ray in Phallobrycon; presence of a simple concentration of glandular tissue on the anterior part of the anal fin; and presence of a developed urogenital papilla in male specimens (Ref. 81937).
Description: Dorsal fin ii, 8; anal fin iv, 18-23; pectoral fin i, 11-13; pelvic fin i, 7 (Ref. 81937). |
| Found in the main channel of rivers with fast flowing and rather shallow clear waters, with abundance of rocks and thick sand (Ref. 81937). |
|
Least Concern (LC); Date assessed: 07 November 2018 Ref. (130435)
|
| harmless |
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