4a. scales on head reaching to anterior part of interorbital space , not reaching nostrils. preorbital naked, suborbital more or less scaly.......5
4b. scales on head reaching to nostrils . preorbital naked, suborbital more or less scaly.......6
4c. scaleson head reaching to beyond nostrils almost to tip of snout. preorbital and suborbital scaly. each caudal lobe with a median longitudinal dark band .........................oelestinus