Adjective
Having the vertebral column evidently continued into the upper lobe of the tail, which is usually longer than the lower one, as in sharks.
Source: Webster's dictionarySharks possess a heterocercal caudal fin in which the dorsal portion is usually noticeably larger than the ventral portion. Source: Internet
One of the primary characteristics present in most sharks is the heterocercal tail, which aids in locomotion. citation Body covering Chondrichthyans have toothlike scales called dermal denticles or placoid scales. Source: Internet