Diagnosis: A moderately-sloped head and bicuspid teeth in the outer row of the jaws place this species in Maylandia (Ref. 86409). Male M. mossambica from Chiloelo are distinguished from those of all other members of Maylandia by the absence of a black submarginal band in the dorsal and by black streaks in the caudal and in the posterior portion of the dorsal fin; male M. mossambica from Chinuni are distinguished from those of all other Maylandia by the absence of a black submarginal band in the dorsal and by a narrow black submarginal band in the anal fin; male M. mossambica from Lumessi are distinguished from all other Maylandia, except M. aurora, M. chrysomallos, and M. xanthos by the absence of a black submarginal band in the dorsal, a yellow ventral half of the head, breast, and dorsal fin, and a light-blue nape; male M. mossambica from Lumessi population differ from those of M. chrysomallos by a yellow dorsal fin which is light-blue in the latter (Ref. 86409). Maylandia mossambica differs from M. aurora by more vertical bars below the dorsal, 7–9 vs. 6, and from M. xanthos by a shorter lower jaw, 27.9–33.8% of head length vs. 34.6–36.7% (Ref. 86409). Based on the colour pattern, female M. mossambica cannot reliably be distinguished from those of most other members of the Aurora group but have 7 or 8 bars below the dorsal fin vs. 6 bars in M. aurora (Ref. 86409).

Description: Dorsal snout profile slightly concave to straight; mouth cleft with slightly downward angle; jaws isognathous; teeth on dentary in two to four rows, on premaxilla in two to four rows; outer row teeth typically bicuspid anteriorly and unicuspid posteriorly, inner rows tricuspid, innermost row unicuspid; lower pharyngeal jaw with numerous slender teeth with teeth in posterior row slightly larger; portion of upper dental arcade normally exposed when mouth closed; tips of teeth in premaxilla and dentary in V-shaped line with anteriormost in upper and lower jaw furthest apart and not touching in closed mouth (Ref. 86409). Lateral scales ctenoid (Ref. 86409).

Colouration: Breeding males at Lumessi typically with gray/blue ground colour with posterior edge of scales gold in dorsal 2/3 and faint lateral barring; ventral third gold; ventral third of head gold; cheekd yellow, gukar region orange, interorbital light blue/gray with gray/green interorbital bar, and gray/black opercular spot; proximal 2/3 of dorsal fin gold, remainder blue/gray; caudal fin gold with yellow/gray membranes; proximal 1/3 of anal fin orange, distal 2/3 blue/gray; pelvic fin orange; pectoral-fin rays orange with clear membranes (Ref. 86409). Breeding males from Chinuni typically with light-blue ground colour and 7 gray bars below dorsal fin, caudal peduncle blue/gray; head light blue dorsally with 1 dark interorbital bar, purple cheek and operculum, pale yellow gular region, and gray opercular spot; dorsal fin blue with orange tips; caudal-fin rays pale blue with light-orange membranes; anal fin gray with a black submarginal band, white lappets, and 2-3 yellow ocelli; pelvic fin dark gray with white leading edge and broad black submarginal band; pectoral fins clear (Ref. 86409). Breeding males from Chiloelo with light-blue ground colour and 7 or 8 dark blue bars below dorsal fin; belly white with area between pelvic fins orange; head light-blue with 1 gray interorbital bar, gular region orange; dorsal fin light-blue with white lappets, posterior third of rayed portion with black membranes; caudal fin black with light-blue rays; anal fin light blue/gray with 2-6 orange ocelli and black submarginal band and white lappets; pelvic fin clear, except for white leading edge and gray/black band; pectoral fins clear with gray rays and yellow/orange base (Ref. 86409). Females of all three populations of Maylandia mossambica indistinguishable; body gray/brown laterally; belly white; head brown, cheek with green highlights, gular region white; dorsal fin gray with green spots and orange lappets; orange tips on rays; caudal fin clear with orange/yellow margin and small blue spots throughout; anal fin clear in proximal half, orange/brown in distal half; pelvic fin clear except for first two orange/brown membranes; pectoral fin clear (Ref. 86409).