Diagnostic Description
provided by Fishbase
The unique color pattern of the body consisting of a black midlateral stripe which extends from the posterior margin of the eye to the median caudal-fin rays distinguishes Hemigrammus ataktos from all congeners which possess dark stripe or thin line extending approximately from the humeral blotch or from the vertical through dorsal-fin origin to the caudal fin. It differs also from all congeners, except H. filamentosus Zarske, by having elongated anteriormost portions of the dorsal, pelvic, and anal fins in mature males (Ref. 96858).Description: dorsal-fin rays ii,9-10; anal- fin rays iv-vi, 20-24; pectoral-fin rays i,10-12; pelvic-fin rays i,7 (Ref. 96858).
Morphology
provided by Fishbase
Dorsal soft rays (total): 1112; Vertebrae: 33 - 34
