Jenynsia unitaenia Ghedotti & Weitzman 1995

With a single midlateral stripe without associated dorsolateral or ventrolateral stripes or blotches; greater than 13 relatively long and slender gill rakers on ventral limb of first gill arch; and a slightly subterminal mouth.

Dorsal soft rays (total): 10 - 12; Analsoft rays: 9 - 10

Found in streams.