Protosuchus richardsoni Brown, 1933

Nesbitt, Sterling J., 2011, The Early Evolution Of Archosaurs: Relationships And The Origin Of Major Clades, Bulletin of the American Museum of Natural History 2011 (352), pp. 1-292 : 43

Protosuchus richardsoni Brown, 1933

(fig. 12C–D)

AGE: Hettangian, Early Jurassic ( Tanner and Lucas, 2007).

OCCURRENCE: Ward’s Terrace, upper half of the Moenave Formation, Arizona.

HOLOTYPE: AMNH FR 3016, crushed skull and nearly complete skeleton missing the manus.

REFERRED MATERIAL: MCZ 6727, threedimensionally preserved skull and nearly complete skeleton; UCMP 131827, posterior portion of a skull and disarticulated skeleton; UCMP 130860, complete skull split longitudinally; UCMP 36717, postcranial skeleton.

REMARKS: Remains of Protosuchus richardsoni are known from a limited number of closely spaced localities along Ward’s Terrace in the sandstones of the Moenave Formation in Arizona. The taxon is represented by nearly every skeletal element in extraordinary detail including portions rarely preserved (braincase and palate). P. richard- soni forms part of the definition of Crocodyliformes and lies at a critical junction between basal crocodylian-line archosaurs and Crocodylia .

KEY REFERENCES: Brown, 1933; Colbert and Mook, 1951; Crompton and Smith, 1980; Clark, 1986.