Gorgonichthys

Gorgonichthys is extinct monospecific genus of large arthrodire placoderm.

Fossils are found in the Upper Famennian Cleveland Shales of Late Devonian in Ohio.

Gorgonichthys had sharp, pointed edges on the dental plates of the upper and lower jaws.

[1] With a headshield length of up to 70 cm (28 in),[2] it is estimated to have been comparable to the size of Dunkleosteus.

The cladogram below shows the phylogeny of Gorgonichthys:[4] Coccosteomorphi Rhachiosteus pterygiatus Eastmanosteus calliaspis Eastmanosteus pustulosus Kiangyousteus yohii Golshanichthys asiatica Westralichthys uwagedensis Dunkleosteus raveri Dunkleosteus terrelli Dunkleosteus amblyodoratus Heterosteus ingens Yinosteus major Tapinosteus heintzi Bullerichthys fascidens Kendrickichthys cavernosus Bruntonichthys multidens Dinichthys herzeri Hadrosteus rapax Gorgonichthys clarki Heintzichthys gouldii Pachyosteus bulla Gymnotrachelus hydei Stenosteus angustopectus Brachyosteus dietrichi Melanosteus occitanus Rhinosteus parvulus According to a 2022 Jobbins et al. study, Gorgonichthys was found to be more related to Heintzichthys than Gymnotrachelus, potentially making Gorgonichthys a member of Selenosteidae.

Gorgonichthys jaws.
The infragnathals (lower jaws) of Gorgonicthys with a 1-liter water bottle for scale (bottle is approximately 23 cm tall). These specimens were collected from the Cleveland Shale and are in the collections of the Cleveland Museum of Natural History 's Department of Vertebrate Paleontology.
Ventral plates of Gorgonichthys clarki