Skeleton of head of a perch. *"f", frontal *"t," turbinal *"po", preorbital *"io", infraorbital ring *"mx", maxillary *"pmx," premaxillary *"m", mandible *"d," dentary bone *"pt," posttympanic *"s," suprascapula *"o," opercle *"so," subopercle *"pr," preopercle *"iop," interopercle *"br," branchiostegal rays