thumb|Front portion of the body of Ctenacanthus concinnus (originally described as "C. clarkii") from the Devonian-age [[Cleveland Shale]] Ctenacanthus (from , 'comb' and , 'spine') is an extinct genus of ctenacanthiform chondrichthyan. Remains have been found in the Bloyd Formation (Carboniferous Period) of Arkansas and the Cleveland Shale (Devonian Period) of Ohio in the United States and in South America.
thumb|Front portion of the body of Ctenacanthus concinnus (originally described as "C. clarkii") from the Devonian-age [[Cleveland Shale]] Ctenacanthus (from , 'comb' and , 'spine') is an extinct genus of ctenacanthiform chondrichthyan. Remains have been found in the Bloyd Formation (Carboniferous Period) of Arkansas and the Cleveland Shale (Devonian Period) of Ohio in the United States and in South America.
== Valid species == Ctenacanthus buttersi St. John & Worthen, 1883 Ctenacanthus chemungensis Claypole, 1885 Ctenacanthus concinnus Newberry, 1875 Ctenacanthus denticulatus McCoy, 1848 Ctenacanthus formosus Newberry, 1873 Ctenacanthus harrissi Caster, 1930 Ctenacanthus lamborni Wells, 1944 Ctenacanthus major Agassiz, 1843 Ctenacanthus pellensis St. John & Worthen, 1883 Ctenacanthus sculptus St. John & Worthen, 1875 Ctenacanthus terrelli Newberry, 1889 Ctenacanthus tumidus Newberry, 1889 Ctenacanthus vetustus Eastman, 1902 Ctenacanthus wrightii Newberry, 1884 Ctenacanthus amblyxiphias Cope, 1891
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).