Smallmouth Grunt
Brachygenys chrysargyrea
    Ecological Descriptors
Habitat Size (cm) Diet Behaviour Sex 
Co, R (S) 23 Pla, Noct Sh F
Adult: Fish with an elongated, cylindrical, body and a notched tail. Body with five or six
horizontal yellow stripes over a bluish silver to silvery-white background. N.B. Has one longitudinal stripe running UNDER the pectoral fin, unlike the similar Striped Grunt (which also lacks the yellow fins). Mouth noticeably smaller than in other grunts. All fins are yellow, except pectoral.
Juvenile: 3 dark stripes: 1 from snout through eye to tail base, ending in an upwardly bent elongate black spot on tail fin base: 1 from top of eye back along front 3/4 of lateral line; 1 from above eye along top of back.

Prefer shallow reefs, down to 25 meters. Adults drift in small schools near the bottom, in the shelter of coral formations, whilst Juveniles are found over hard bottoms and around coral reefs or Thalassia grass beds. It forages mostly at night on a diet primarily of zooplankton including copepods, amphipods, ostracods, shrimps, and crab larvae. A presumed example of protective mimicry between the yellow goatfish, Mulloidichthys martinicus, and the smallmouth grunt hasbeen described. The colour and shape resemblances between the two species enable their mixed schooling, and enhance the protection against visually oriented predators for both of species.

Pelagic spawners with eggs hatching pelagic larvae.
Smallmouth Grunt Adult