The flame tetra reaches about 2.5 cm (1 in) in standard length.[4][5][7] The rear half of the body is flame red while the area in front of the dorsal fin is silver crossed by two dark vertical bars. All the fins are red except for the pectoral fins, which are colourless. The tip of the anal fin on the male is black, while on the female the fins have less red colouration but darker tips of the pectoral fins.
