Which main characteristics could be used to separate Squalidae shark from Pristiophoridae shark?

The Pristiophoridae are the sawsharks, Squalidae the Dogfish sharks, as the name indicates, the Sawsharks have an elongated and flattened rostrum along the length of which the teeth are distributed where they stick out sideways resembling a saw, Squalids have a more 'typical' shape. In addition the Pristiophorids have long barbels halfway along the length of the rostrum which Squalids lack as well as a caudal fin separated into a distict upper and lower lobe wheras Squalids the caudal fin is a single lobe.