Described in the 1800s and discussed in aquarium literature over 50 years ago, this species is extremely rare in shops.  It is distinguished within the tetras in that the male develops an elongated fins and a swordtail extending from the lower caudal lobe.  Males also develop some soft yellow and orange color contrasting against its silvery scales - from a distance the fish appear mostly silver. The fish are very hyper and always on the move.  This species will provide lots of action - comparable to most active danios.

The Swordtail Characin is a glandulocaudin - one of the few tetra species where the male inseminates the female, and later the female expels both eggs and the captured sperm which can yields over 100 young tetras.  In my experience, I have had success by placing a single plump female in a 5 gallon tank with just a couple of java ferns.  By the end of the next day I can see the eggs (some on the plants, some on the tank floor), which the female seems to ignore.  My last spawn produced 195 fry which I am raising.   But this lot is of two adults, a male and a female.