a1 P.O. Box 2217, Petrified Forest National Park, Petrified Forest, AZ 86028, USA. Email: William_Parker@nps.gov
a2 Department of Geological Sciences, The University of Texas at Austin, Austin, TX 78712, USA
a3 Mesalands Community College, Tucumcari, NM 88401, USA
a4 Denver Museum of Nature and Science, Denver, CO 80205, USA
The genus Machaeroprosopus has long been considered invalid because the type specimen of the Late Triassic phytosaur species, M. validus, has been lost. Re-examination of the primary literature regarding the establishment of the Late Triassic phytosaur genus Machaeroprosopus demonstrates that M. buceros is the correct type species, not M. validus. Thus, the genus level name Machaeroprosopus has priority over the genera Pseudopalatus and Arribasuchus and all nominal species should be reassigned. Reassignment of these species to Machaeroprosopus satisfies the requirements of the International Code of Zoological Nomenclature (ICZN) and preserves historical context. The name Pseudopalatinae is retained as the valid clade name for these phytosaurs because its usage falls outside of the ICZN.
(Received January 12 2012)
(Accepted December 06 2012)