Definition of acanthodian in US English:



  • A small spiny-finned, jawed fossil fish of a group found chiefly in the Devonian period.

    Class (or subclass) Acanthodii

    • ‘Many acanthodians bore teeth directly on the Meckelian cartilage, which was ossified in most cases (like placoderms), but may have remained cartilaginous in others (like sharks).’
    • ‘But the treasure I did find was in the form of a beautifully preserved large set of fossil fish jaws belonging to an acanthodian.’
    • ‘However, I also examined some other problematical specimens from the Early Devonian of Canada, first described as belonging to acanthodian fishes (named Doliodus), and discovered that they were really sharks' teeth as well.’
    • ‘The first jawed fish in the fossil record are the acanthodians, which first occur in the Late Silurian.’
    • ‘A few acanthodians also lingered into the Cisuralian.’
    • ‘The majority of fossils recovered from the site are acanthodian fish belonging to Mesacanthus and Ischnacanthus with occasional Euthacanthus, Parexus and Climatius.’
    • ‘In addition, it has several features, such as the fin spines and characters of the shoulder plate, which are associated with placoderms, chondrichthyans, or acanthodians.’
    • ‘Gill rakers are found in both chondrichthyans and in Osteichthyes, as well as acanthodians.’
    • ‘But the play of light and color, the universe of vision is for others - foolish, energy-wasting acanthodians and lungfish, easily confused and misled in the dim, murky bottomland.’
    • ‘The acanthodian Mesacanthus shows this relationship well.’
    • ‘In addition, there are archaic elements, such as the antiarch and arthrodire placoderms as well as acanthodians.’
    • ‘It has been reported, based on as-yet unpublished data, that the acanthodian Diplacanthus solidus is indicative of Eifelian age.’
    • ‘Some layers were quite rich in small fish remains, like the interesting double-pronged sharks' teeth and the fin-spines of acanthodian fishes.’
    • ‘Cheirolepis, and even acanthodians, clearly have them.’
    • ‘Both blocks are free of plant remains, but the specimen from the fish bed lithology is preserved in proximity to a fish coprolite containing scales and spines of acanthodian fish.’
    • ‘As we have mentioned, it is likely that the opercular is serially homologous with the branchiostegal rays and that both began as a series of dermal opercular scales as is observed in some acanthodians.’
    • ‘The acanthodian Acanthodes, the palaeoniscoid Platysomus, and the fusiform palaeoniscoids are represented by small’
    • ‘Other fish found in the adjacent sandstone beds are the acanthodian Diplacanthus Agassiz, 1844, the dipnoan Fleurantia Graham-Smith and Westoll, 1937, and the sarcopterygian Eusthenopteron Whiteaves, 1881.’


Mid 19th century: from modern Latin Acanthodii (from acantho-) + -an.