Acanthorhachis

An extinct chondrichthyian genus

Acanthorhachis is an enigmatic extinct genus of chondrichthyan from the Carboniferous period. Its name is derived from the Greek word acanthos meaning "spine" and the Greek suffix for spine, -rhachis. This is due to the spine-like dermal denticles and their subsidiary spines, which coated the exterior of the animal. The authors who erected this genus suggested the common name "The Spiny Spined Shark." The type species Listracanthus spinatus was in 1896 named by Herbert Bolton.

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