Isalorhynchus is an extinctgenus of hyperodapedontinerhynchosaur from the late Triassicperiod (Carnian stage) of Toliara Province, southwestern Madagascar. It is known from the holotype MDE-R18, a nearly complete maxilla and from other specimens from the same locality, Malio River area. It was found in the Makay Formation (or Isalo II) of the Morondava Basin (or Isalo beds). It was first named by Eric Buffetaut in 1983 and the type species is Isalorhynchus genovefae.[1] The majority of Isalorhynchus specimens are isolated jaw bones, but two nearly complete skeletons were found in 1998.[2] Langer et al., 2000 concluded that Isalorhynchus is a synonym of Hyperodapedon and referred it to a new species of Hyperodapedon.[3] Whatley, 2005 retained this genus as valid with a description of new materials in her PhD thesis.[4] Montefeltro et al., 2010 and Langer et al., 2010 accepted Isalorhynchus as valid genus.[5][6]
Phylogeny
Isalorhynchus in a cladogram based on Ezcurra et al. (2016):[7]
^Eric Buffetaut (1983). "Isalorhynchus genovefae, n. g. n. sp. (Reptilia, Rhyncocephalia), um nouveau Rhyncosaure du Trias de Madagascar". Annales de Paléontologie. 1983: 465–480.
^Whatley, R.L.; Flynn, J.J.; Parrish, J.M.; Simpson, W.; Wyss, A.R. (1999). "Isalorhynchus revisited: two rhynchosaur skeletons from southwestern Madagascar". Journal of Vertebrate Paleontology. 19 (3 Suppl): 84A. doi:10.1080/02724634.1999.10011202.
^M. Langer; M. Boniface; G. Cuny; L. Barbieri (2000). "The phylogenetic position of Isalorhynchus genovefae, a Late Triassic rhynchosaur from Madagascar". Annales de Paléontologie. 86 (2): 101–127. Bibcode:2000AnPal..86..101L. doi:10.1016/s0753-3969(00)80002-6.
^Whatley, R. L. (2005). Phylogenetic relationship of Isalorhynchus genovefae, the rhynchosaur (Reptilia, Archosauromorpha) from Madagascar (PhD Thesis). University of California, Santa Barbara. 276 pp.
^Felipe Chinaglia Montefeltro; Max Cardoso Langer; Cesar Leandro Schultz (2010). "Cranial anatomy of a new genus of hyperodapedontine rhynchosaur (Diapsida, Archosauromorpha) from the Upper Triassic of southern Brazil". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 101 (1): 27–52. Bibcode:2010EESTR.101...27M. doi:10.1017/S1755691010009060. S2CID129472459.
^Max C. Langer; Felipe C. Montefeltro; David E. Hone; Robin Whatley; Cesar L. Schultz (2010). "On Fodonyx spenceri and a new rhynchosaur from the Middle Triassic of Devon". Journal of Vertebrate Paleontology. 30 (6): 1884–1888. Bibcode:2010JVPal..30.1884L. doi:10.1080/02724634.2010.521901. S2CID53405231.