 The nostrils are placed almost at the tip of the snout and have long, tapering barbels in front and well-developed skin flaps and grooves around the incurrent openings.A pair of obvious grooves connect the nostrils to the small, almost transverse mouth.There are 32–34 upper tooth rows and 21–29 lower tooth rows; each tooth has an upright, awl-shaped central cusp and a pair of lateral cusplets.