soft rays: 24;
Vertebrae: 26. Pale bluish in life. Chin with a median longitudinal fold. Scales tiny, closely packed, non imbricate except posteriorly on caudal peduncle. 1st dorsal higher than 2nd fin; rays of 3rd to 5th spines very long and filamentous. Pale markings on head. Named uroditaenia (Greek) in reference to the 2 dark bands on the caudal fin.