This would have been true, if Procheneosaurus Matthew 1920 was not a nomen nudum. This paper, a lay article on Canadian dinosaurs, lacks an adequate enough definition of what Procheneosaurus is, among other inadequacies. He literally only states: "(5) Procheneosaurus, â a small kind with a little bill and short round head. A fine skeleton is on exhibition in the American Musuem.". This appears inadequate as any diagnosis would go, and the text should not be taken as a diagnosis just to tick off on a taxonomic checkbox.Also, it should be noted that the holotype of Tetragonosaurus praeceps Parks is a ROM specimen, and not that same specimen that Matthew was referring to in his article. A perusal of Parks' paper reveals no reference made to Matthew's 'Procheneosaurus' or to the American Museum specimen, so Tetragonosaurus shouldn't even be considered a replacement name for Procheneosaurus.Given this second point, Procheneosaurus should be considered an invalid genus name, given it lacks a fixed type species (ICZN Art. 67.1).On Thursday, 17 September 2020, 8:07:55 am AEST, Tyler Greenfield <tgreenfield999@gmail.com> wrote:The conserved genusÂProcheneosaurus Matthew, 1920 has priority over Lambeosaurus Parks, 1923 if the two genera are considered synonymous. However, the subsequently designated type species of Procheneosaurus, Tetragonosaurus praeceps Parks, 1931, does not have priority over the type species of Lambeosaurus, Lambeosaurus lambei Parks, 1923. If the two species are considered synonymous, the correct combination would be Procheneosaurus lambei (Parks, 1923).On Wed, Sep 16, 2020 at 4:33 PM Stephen Poropat <stephenfporopat@gmail.com> wrote:Presumably because the type species of Procheneosaurus (Tetragonosaurus praeceps) was not named until eight years after Lambeosaurus lambei.--On Thu, 17 Sep 2020 at 07:09, Ethan Schoales <ethan.schoales@gmail.com> wrote:It's an officially conserved name and it's older than Lambeosaurus, so why isn't it used?Dr Stephen F. PoropatPostdoctoral Researcher (Palaeontology)Faculty of Science, Engineering and TechnologySwinburne University of TechnologyApplied Sciences Building, John StHawthorn, VictoriaAustralia 3122Phone: +61 3 9214 5152Alternate email: sporopat@swin.edu.auResearch Associate
Australian Age of Dinosaurs Museum of Natural History1 Dinosaur Drive, The Jump-UpWinton, QueenslandAustralia 4735