Carnosaurs

Hunt, A. P. & Lucas, S. G., 1992, Stratigraphy, paleontology and age of the Fruitland and Kirtland Formations (upper Cretaceous), San Juan Basin, New Mexico, New Mexico Geological Society, New Mexico Geological Society 43 rd Annual Fall Field Conference Guidebook, pp. 217-239 : 228

Carnosaurs

— Carnosaur specimens are rare in the Fruitland and Kirtland Formations. Although generically indeterminate, one specimen worthy of note is NMMNH P-20879 ( Fig. 8 M), a pedal phalanx from the Kirtland Member. NMMNH P- 20879 is comparable with phalanges of Tarbosaurus ( Molnar et al., 1990, fig. 6.12E) and undoubtedly represents the third phalanx of the fourth digit of the right pes.

The record of tyrannosaurids in the San Juan Basin is poor, with only one partial skeleton (of Aublysodon ) known from either the Fruit ­ land or Kirtland Formations ( Lehman and Carpenter, 1990). It is not even clear if this taxon is a tyrannosaur ( Molnar et al., 1990). The only questionable record of Tyrannosaurus is based on an isolated tooth from the Naashoibito Member of the Kinland Formation ( Lucas et al., 1987). Tyrannosaurid taxonomy is in a state of flux, as is obvious if the recent classifications of Paul (1988), Molnar et al. (1990) and Carpenter (1990) are compared. Until the family is revised and the osteology of some important taxa (e.g.. Tyrannosaurus ) are described, it is difficult to identify fragmentary specimens.

Figures

FIGURE 8. Dinosaur bones from the Fruitland and Kirtland Formations. A, Chevron of indeterminate hadrosaur (NMMNH P-1043) from the upper Fruitland Formation in posterior view. B-C, Ribs of indeterminate hadrosaur (NMMNH P-1043) from the upper Fruitland Formation in medial view with healed fractures D-E, Edmontosaurus saskatchewanenss, right humerus (NMMNH P-1041) from the Naashoibito Member of the Kirtland Formation in posterior (D) and anterior (E) views F, Posterior left tibia and astragalus of indeterminate hadrosaur (NMMNH P-1043) from the upper Fruitland Formation in posterior view. G Left femur of indeterminate hadrosaur (NMMNH P-1043) from the upper Fruitland Formation in posterior view. H. Articulated left metatarsals 2 and 3 of an indeterminate hadrosaur (NMMNH P-1043) from the upper Fruitland Formation in anterior view. I-J, Indeterminate nodosaurid osteoscutes (NMMNH P-1078) from the Naashoibito Member of the Kirtland Formation in dorsal view. K-L, Indeterminate nodosaurid osteoscutes (NMMNH P-20880) from the upper Fruitland Formation in dorsal view. M, Third phalanx of fourth digit of pes of a tyrannosaurid (NMMNH P-20879) from the Naashoibito Member of the Kirtland Formation Scale bars are 10 cm except for G (50 cm) and I (1 cm).