Eutretauranosuchus delfsi Mook, 1967

Pritchard, Adam C., Turner, Alan H., Allen, Eric R. & Norell, Mark A., 2013, Osteology of a North American goniopholidid (Eutretauranosuchus delfsi) and palate evolution in Neosuchia, American Museum Novitates 2013 (3783), pp. 1-56 : 7

Eutretauranosuchus delfsi Mook, 1967

HOLOTYPE: CMNH 8028 , nearly complete skull and complete mandibles ( figs. 2 , 3 ).

REFERRED SPECIMENS: BYU 17628, complete skull and articulated mandibles.

NEWLY REFERRED SPECIMEN: AMNH FARB 570, complete skull ( figs. 5–15 ); partial right hemimandible ( fig. 16 ); partial cervical series with associated osteoderms ( fig. 1 ), three isolated osteoderms, distal portion of a left femur ( fig. 17 ).

EMENDED DIAGNOSIS: (1) Elongate, platyrostral skull; (2) prominent depression on posterolateral surface of alveolar process of maxilla; (3) subtle emargination of maxillary tooth row, with only a single lateral undulation; (4) broadening of nasals anterior to prefrontals; (5) nasals do not contact external nares; (6) broad, flat interfenestral bar with raised medial rims along supratemporal fenestrae (from Mook, 1967, and Smith et al., 2010: shared with Amphicotylus lucasii [AMNH FARB 5782]); (7) anteroposteriorly elongate palatal opening due to partial contact of palatal processes of maxillae and noncontact of palatal processes of palatines, exposing entire nasopharyngeal canal in ventral view (shared with Calsoyasuchus valliceps [TMM 43631-1]); (8) nasopharyngeal septum formed from diverging vomeral processes anteriorly and midline pterygoid process posteriorly (present in Amphicotylus lucasii [AMNH FARB 5782]); and (9) vomeral septal complex forms X shape in cross section (shared with Amphicotylus lucassii [AMNH FARB 5782]).

LOCALITY: Bone Cabin Quarry, Morrison Formation (Brushy Basin Member), Wyoming, United States of America (fig. 4). Upper Jurassic (Kimmeridgian) ( Foster, 2009).

Figures

FIG. 2. Holotype of Eutretauranosuchus delfsi CMNH 8028 in (A) dorsal and (B) ventral view. See appendix 2 for abbreviations.

FIG. 3. Holotype of Eutretauranosuchus delfsi CMNH 8028 in (A) dorsal and (B) ventral view.

FIG. 5. Eutretauranosuchus delfsi AMNH FARB 570 in (A) dorsal, (B) ventral, and (C) right lateral views. See appendix 2 for abbreviations.

FIG. 6. Eutretauranosuchus delfsi AMNH FARB 570 in (A) dorsal, (B) ventral, and (C) right lateral views.

FIG. 8. Transverse CT sections through the skull of Eutretauranosuchus delfsi AMNH FARB 570. (A) Tra 359, (B) Tra 400, (C) Tra 435, (D) Tra 555, (E) Tra 585, (F) Tra 616. See appendix 2 for abbreviations.

FIG. 12. Transverse CT sections through the skull of Eutretauranosuchus delfsi AMNH FARB 570. (A) Tra 574, (B) Tra 770, (C) Tra 878, (D) Tra 936, (E) Tra 1036, (F) Tra 1116. See appendix 2 for abbreviations.

FIG. 14. Occiput of Eutretauranosuchus delfsi AMNH FARB 570 in posterior view. Dashed lines indicate reconstructed sutures and surfaces. See appendix 2 for abbreviations.

FIG. 15. Transverse CT sections through the skull of Eutretauranosuchus delfsi AMNH FARB 570. (A) Tra 1124, (B) Tra 1159, (C) Tra 1177, (D) Tra 1184, (E) Tra 1195, (F) Tra 1216. See appendix 2 for abbreviations.

FIG. 16. Eutretauranosuchus delfsi AMNH FARB 570. Right hemimandible in lateral view. See appendix 2 for abbreviations.

FIG. 1. Panel mount of Eutretauranosuchus delfsi AMNH FARB 570. The skull has been removed, and the right mandible and cervical region remain.

FIG. 17. Eutretauranosuchus delfsi AMNH FARB 570 postcranial elements. Partial right femur in (A) dorsal, (B) medial, (C) ventral, and (D) lateral views. Partial dorsal osteoderm in (E) dorsal view.