diverticulum pharyngealis

epibranchial organ (a paired dorsal diverticulum at the posterior limit of the pharynx in certain microphagous fishes. Also called gill-helix, pharyngeal organ, or pharyngeal pocket. In all forms with these organs, except some characids, prominent gill rakers extend into the organ dividing its cavity into two parts, one confluent with the pharynx, and one with the opercular cavity. Small food particles, generally plankton, are retained by the rakers, consolidated by mucus and squeezed out into the oesophagus. Found in Heterotidae, Characidae, Chanoidei, Gonorhynchoidei, Clupeidae and Engraulidae)