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The Canjuers sediments are slightly younger than the Solnhofen limestones in Germany. Gyrodus (from Greek: γύρος gyros, 'curved' and Greek: ὀδούς odoús 'tooth') is a genus widely distributed in the Jurassic. Two species, G. circularis and G. hexagonus, are described from Solnhofen. This distinctly elongated looking fish from the Canjuers deposits of about the same age is probably a species not yet described. Diagnosis from Lambers 1991, p. 490 (Genus, emend. Hennig 1906): ”Pycnodontid fishes with the following combination of characters: body form hexagonal; skull without ganoin; dermal bones tuberculated; skull roof composed of frontal, parietal, median dermosupraoccipital, dermosphenotic, dermopterotic, one median and two paired supratemporals; mosaic dermethmoid; snout and cheek region covered with small, polygonal scalelike plates; maxilla half-oval, edentulous; mouth parallel to body axis; gular absent but gular region covered with small scales; two acinaciform branchiostegals; premaxilla with nasal process, bearing two styliform teeth; dentary with four styliform teeth; five longitudinal rows of vomerine teeth, four longitudinal rows of splenial teeth; squamation complete over the whole body, scales towards the caudal smaller than in front, in young specimens tuberculated, in adult specimens reticulated, lacking ganoin, squamation extending between the bases of the dorsal and anal lepidotrichia and covering the basis of the caudal lepidotrichia dorsal and ventral ridgescales with up to 6 spinelets; notochord persistent through life; neural and haemal arches not surrounding the notochord 28—31 paired dorsal elements, 12—14 paired postabdominal elements in front of tail, 12—14 paired ribs; first 10 neural spines autogenous; neural and haemal spines in caudal region with anterior and posterior laminar expansions, strengthened with ridges; curved postcoelomic bone connected to 13th—15th vertebral element; pectoral fin with 25—30 rays; pelvic fin with 10-15 rays; dorsal and anal fins falcate, fin rays bifurcated from their base, transversely segmented, transverse segments tuberculated, dorsal fin 30—40 rays, anal fin about 30 rays; caudal fin stalked, deeply forked; about seven neural spines, about ten hypochordal elements, comprising haemal spines and hypurals, incorporated in the support of the caudal fin, one urodermal, about 40 rays; 7—10 epaxial fin rays; no fulcra; infraorbital canal connected to the preopercular canal, representing the horizontal pitline and more ventrally by a vertical canal, representing the vertical pit-line; supraorbital canal extends into the dermosupraoccipital, where it forms the supratemporal commissure; dorsal lateral line present up to the origin of the dorsal fin.” Identified by M. Ebert, Jura Museum Eichstätt. References: Agassiz, L. (1843). Recherches Sur Les Poissons Fossiles. Tome I (livr. 18). Imprimerie de Petitpierre, Neuchatel xxxii-188. Hennig, G. (1906). Gyrodus und die Organization der Pycnodonten. Palaeontographica, 53,137-208. Kriwet, J. and Schmitz, L. (2005). New insight into the distribution and palaeobiology of the pycnodont fish Gyrodus. Acta Palaeontologica Polonica 50 (1): 49–56. Peyer, K., Charbonnier, S., Allain, R., Läng, É. & Vacant, R. (2014) A new look at the Late Jurassic Canjuers conservation Lagerstätte (Tithonian, Var, France). Comptes Rendus Palevol, Volume 13, Issue 5. Pages 403-420, ISSN 1631-0683.