Description: body slender; head fairly robust; caudal fin usually rounded, in some males rays of upper lobe may be slightly elongated; ripe females possess a large and easily-seen genital papilla (Ref. 52307).

Coloration: body grayish-brown to bluish gray, lighter ventrally; turquoise iridescent blotch often visible on flanks; during certain behavioral situations, dusky vertical bars may be present on body, reaching from back to about middle of body; both sexes usually with red spot directly above eye, always more visible and larger in females (rarely extending to about mid-body); males with many alternating rows of dark and pale spots in caudal fin and in soft dorsal and anal fins, females lack spots in their fins; both sexes may exhibit 1 or (rarely) 2 thin white margins on upper edge caudal fin; males with dark-margined body scales; ripe female with violet belly, sometimes with a reddish flush (Ref. 52307).