Exapophyses

zygapophyses (plate-like joints which lie on the neural arch above the centrum). The term was coined by Samuel Wendell Williston in 1897 during a description of Pteranodon (which he called "Ornithostoma" at the time).^[1] Exapophyses are a defining trait of the pterosaur group Eupterodactyloidea,^[2] although they are also known to occur in some ctenochasmatids.^[3] Rhamphorhynchids have paired, knob-like extensions on the condyle which are occasionally also termed exapophyses, but these extensions are not distinctly offset and are not considered homologous to the exapophyses of eupterodactyloids and ctenochasmatids.^[4]