Mikko's Phylogeny Archive

†Aetosauria – aetosaurs

Note:

Taxonomic and phylogenetic development of Aetosauria has been marred by a recent controversy considering taxonomic status of “Desmatosuchus” chamaensis.
As a common policy of the Archive, I have decided not to take sides at this point, but to wait the official solution of the problem, either by ICZN commission or SVP Ethics commitee.

After Parker, 2007

<==o †Aetosauria Marsh, 1884 (non Lydekker, 1889) [Aëtosauria Marsh, 1884]
   `--o †Stagonolepididae Lydekker, 1887 sensu Heckert & Lucas, 2000
      |?- †Acompsosaurus Mehl, 1915
      |?- †Chilenosuchus Casamiquela, 1981
      |?- †Ebrachosaurus singularis Kuhn, 1936
      |?- †Stegomus arcuatus Marsh, 1896
      |--o †Desmatosuchinae Huene, 1942 sensu Heckert & Lucas, 2000
      |  |-- †Longosuchus meadei (Sawin, 1947) Hunt & Lucas, 1990 [Typothorax meadei Sawin, 1947]
      |  `--+-- †Lucasuchus hunti
      |     `--+-- †Acaenasuchus geoffroyi [juveline Desmatosuchus? (Heckert & Lucas, 2002)]
      |        `--o †Desmatosuchus Case, 1920; U.Trias. NA. [taxonomic history]
      |           |-- †D. haploceros (Cope, 1892)
      |           `-- †D. smalli Parker, 2005 [taxonomic history]
      `--o †Aetosaurinae Marsh, 1884 sensu Heckert & Lucas, 2000
         |--+-- †Coahomasuchus kahleorum Heckert & Lucas, 1999
         |  |-- †Neoaetosauroides engaeus Bonaparte, 1969
         |  `--+--o †Aetosaurus O. Fraas, 1887
         |     |  |-- †A. ferratus O. Fraas, 1887
         |     |  `?- †A. crassicauda E. Fraas, 1907 [conspecific with A. ferratus sensu Parrish, 1994]
         |     |-- †Aetosauroides scagliai
         |     `--o †Stagonolepis Agassiz, 1844 [taxonomic history]
         |        |-- †S. robertsoni Agassiz, 1844 [taxonomic history]
         |        `-- †S. wellesi (Long & Bellew, 1985) Murray & Long, 1989 [taxonomic history]
         `--o †Typothoracisinae Parker, 2007
            |--+-- †Redondasuchus reseri
            |  `--o †Typothorax Cope, 1892; U.Trias. NA.
            |     |-- †T. antiquum Lucas, Heckert & Hunt, 2002
            |     `-- †T. coccinarum Cope, 1892 [incl. Episcoposaurus horridus Cope, 1887]
            `--o †Paratypothoracisini Parker, 2007
               |-- TTUP 545
               `--+-- †“Desmatosuchus” chamaensis (Zeigler, Heckert & Lucas, 2002) [taxonomic history]
                  `-- †Paratypothorax andressorum Long & Bellew, 1985

Alternative phylogenies of Aetosauria (from Parker, 2007):

Parrish, 1994:

<==o †Stagonolepididae
   |-- †Aetosaurus
   `--+-- †Neoaetosauroides
      |--+-- †Aetosauroides
      |  `-- †Stagonolepis
      `--+-- †Longosuchus
         `--+-- †Desmatosuchus
            `--+-- †Typothorax
               `-- †Paratypothorax
    

Heckert et al., 1996:

<==o †Stagonolepididae
   |-- †Aetosaurus
   `--+--+-- †Aetosauroides
      |  `-- †Stagonolepis
      `--+-- †Neoaetosauroides
         `--+-- †Longosuchus
            |-- †Desmatosuchus
            `--+-- †Paratypothorax
               `--+-- †Rodondasuchus
                  `-- †Typothorax
    

Heckert & Lucas, 1999:

<==o †Stagonolepididae
   |--o †Aetosaurinae
   |  `-- †Aetosaurus
   `--+--o †Stagonolepidinae
      |  |-- †Coahomasuchus
      |  `-- †Stagonolepis
      `--o †Desmatosuchinae
         |-- †Neoaetosauroides
         `--+--+-- †Longosuchus
            |  `-- †Paratypothorax
            `--+-- †Typothorax
               `-- †Desmatosuchus
    

Corrected typology of
Heckert & Lucas, 1999:

<==o †Stagonolepididae
   |--o †Aetosaurinae
   |  `-- †Aetosaurus
   `--+--o †Stagonolepidinae
      |  |-- †Aetosauroides
      |  `-- †Stagonolepis
      `--+--+-- †Calyptosuchus
         |  `--+-- †Coahomasuchus
         |     `--+-- †Redondasuchus
         |        `-- †Typothorax
         `--o Desmatosuchinae
            |-- †Neoaetosauroides
            `--+-- †Paratypothorax
               `--+-- †Longosuchus
                  `--+-- †Lucasuchus
                     `--+-- †Acaenosuchus
                        `-- †Desmatosuchus
    

Kischlat, 2000:

<==o †Stagonolepididae
   |-- †Aetosaurus
   `--+--+-- †Coahomasuchus
      |  `--+-- †Redondasuchus
      |     `-- †Typothorax
      `--+-- †Aetosauroides
         |-- †Calyptosuchus
         |-- †Stagonolepis
         `--+-- †Neoaetosauroides
            `--+-- †Paratypothorax
               `--+-- †Longosuchus
                  `--+-- †Lucasuchus
                     `--+-- †Acaenosuchus
                        `-- †Desmatosuchus
    

Harris et al., 2003:

<==o †Stagonolepididae
   |-- †Aetosaurus
   `--+--+-- †Aetosauroides
      |  `-- †Stagonolepis robertsoni
      `--+--+-- †Stagonolepis wellsi
         |  `--+-- †Coahomasuchus
         |     `--+-- †Redondasuchus
         |        `-- †Typothorax
         `--+-- †Neoaetosauroides
            `--+-- †Paratypothorax
               `--+-- †Longosuchus
                  `--+-- †Lucasuchus
                     `--+-- †Acaenosuchus
                        `-- †Desmatosuchus
    

Reference(s):

• Heckert, A. B. & Lucas, S. G., 1999: A new aetosaur (Reptilia: Archosauria) from the Upper Triassic of Texas and the phylogeny of aetosaurs.
  –Journal of Vertebrate Paleontology: Vol. 19, #1, pp. 50-68
• Heckert, A. B. & Lucas, S. G., 2002: South American occurences of the Adamanian (Late Triassic: Latest Carnian) index taxon Stagonolepis (Archosauria: Aetosauria) and their biochronological significance.
  –Journal of Paleontology: Vol. 76, #5, pp. 852-863
• Lucas, S. G., Heckert, A. B. & Hunt, A. P., 2002: A new species of the aetosaur Typothorax (Archosauria: Stagonolepididae) from the upper Triassic of east-central New Mexico.
  –New Mexico Museum of Natural History and Science Bulletin: Vol. 21, pp. 221-233
• Lucas, S. G., Hunt, A. P. & Spielmann, J. A., 2006: Rioarribasuchus, a new name for an aetosaur from the Upper Triassic of north-central New Mexico.
  –New Mexico Museum of Natural History and Science Bulletin: Vol. 37, 581-582
• Parker, W. G., 2005: A new species of the Late Triassic aetosaur Desmatosuchus (Archosauria: Pseudosuchia).
  –Comptes Rendus de l'Académie des Sciencies, Paris: Palevol: Vol. 4, pp. 327-340
• Parker, W. G., 2007: Reassessment of the aetosaur ‘Desmatosuchus’ chamaensis with a reanalysis of the phylogeny of the Aetosauria (Archosauria: Pseudosuchia).
  –Journal of Systematic Palaeontology: Vol. 5, #1, pp. 41-68 [doi: 101017/s1477201906001994]
• Parrish, J. M., 1994: Cranial osteology of Longosuchus meadei and the phylogeny and distribution of the Aetosauria.
  –Journal of Vertebrate Paleontology: Vol. 14, #2, pp. 196-209
• Zeigler, K. E., Heckert, A. B. & Lucas, S. G., 2002: A new species of Desmatosuchus (Archosauria: Aerosauria) from the upper Triassic of the Chama Basin, north-central New Mexico.
  –New Mexico Museum of Natural History and Science Bulletin: Vol. 21, pp. 215-219