Pelagic open water; commonly recorded in shallow
vegetated inshore areas, especially when females
release fry.
Geographic distribution:
Lake-wide in Lake Malawi.
Typical adult size:
Up to about 20 cm standard length (approximately
25 cm total length).
Sexual dimorphism:
Males have bright orange pelvic fins and a dark
blue-grey back; females and immatures show a
greenish dorsal coloration.
Diet:
Juveniles feed mainly on crustacean zooplankton;
with growth the species shifts to piscivory, taking
larvae and juveniles of small schooling fishes,
especially Engraulicypris sardella (usipa).
Breeding:
Maternal mouthbrooder. Ripe individuals recorded in
multiple months of the year. Sexual maturity from
about 109 mm SL in males and about
130 mm SL in females. Broods relatively small
(approximately 52–76 eggs), egg diameter usually up
to about 4 mm. Females migrate into sheltered,
weedy inshore areas to release fry.
Special notes:
Originally described from dried half-skins collected
during the Livingstone expedition. Distinguished by
relatively small, closely packed teeth and a deep
cheek. For a long time frequently confused with
R. macrophthalmus, as both reach similar size
and share similar male breeding coloration; much
historical ecological information may therefore
include mixed records.
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