 Key variations that differentiate this genus from all other families are the shape of the animal's skull, jaw muscles, and gas bladder — which fish use to rise and sink in water.The gas bladder has paired diverticulae, while other catfish families either have no diverticulae or singular diverticulae.Some external characteristics that may help distinguish this fish include nostrils set far apart, the presences of nasal barbels, maxillary barbels placed above the lip distantly from the corner of the mouth, and a rounded caudal fin.