One of the newer and desired tetra species.  Unusual and conspicuous black line on upper caudal lobe running across anal fin. I find the adults to be a little high-strung -- forming tight groups and schools, and attacking food with lightning strikes.  Sexual dimorphism is not easy to recognize for this species.  They seem to be prolific, as I spawned a group of five adults over a spawning grid and obtained about 400 fry.  This 'lot' is a sampling from the fry/juveniles that I am growing up.