Melanotaenia rubrivittata is distinguished by the following combination of characters: IV-VI-I,9-12 (usually V-I,10-11) dorsal-fin rays; I,17-21 (usually I,18-20) anal-fin rays; 10-13 (usually 11-12) pectoral-fin rays; 32-33 scales on lateral line, 13-16 (usually 14-15) predorsal scales; 12 scales around caudal peduncle; 12-14 gill rakers on first arch; 11-16 (average 8.9) scales covering cheek (preopercle); snout length 3.2 (3.0-4.3) in HL; average body depth of adult males 37.7 % SL; color in life brilliant neon blue on upper two-thirds of body with five red stripes (one between each scale row); ventral portion of head and body silvery white to blue with slight pinkish hue; first dorsal fin blue; second dorsal fin blue with red basal stripe and broad red zone encompassing outer margin and posterior portion of fin; anal fin bluish with red basal stripe and red outer margin; caudal fin red, grading to bluish or translucent along posterior margin (Ref. 111039).