Bryconops melanurus
Bryconops melanurus, sometimes called the tail-light tetra, is a small species of freshwater fish from South America that primarily preys on insects. It lives in small schools and is an active swimmer, which means that it requires open space in its habitat. Nonetheless, it does not demonstrate a strong preference for any one biotope within its native range. Description Bryconops melanurus reaches a maximum total length of about 13.2 cm (5.2 in), which puts it on the larger side of the genus Bryconops. The head is slender, with a pointed snout, and B. melanurus lacks a humeral spot of the kind frequently seen in congeners (such as B. humeralis and B. inpai). B. melanurus shares aspects of its jaw structure, which is rather lengthened, with B. inpai, B. affinis, and B. giacopinii. (This was used to place giacopinii in the genus Bryconops instead of its originally described Autanichthys.) Bryconops melanurus is a silvery, slender fish with a darker back. The caudal fin has distinctive markings, but lacks a well-formed ocellus (eyespot). There is a dark stripe about the width of the pupil that veers from the center of this fin up towards the dorsal lobe, and the caudal-fin margins are