Almas ukhaa

Pei, Rui, Norell, Mark A., Barta, Daniel E., Bever, G. S., Pittman, Michael & Xu, Xing, 2017, Osteology of a New Late Cretaceous Troodontid Specimen from Ukhaa Tolgod, Ömnögovi Aimag, Mongolia, American Museum Novitates 2017 (3889), pp. 1-48 : 3

Almas ukhaa , new taxon

HOLOTYPE: IGM 100 /1323, a skull and mandible and with partial articulated postcranial skeleton ( figs. 1 , 2 , 3 , 6 , 7 , 8 , 9 ).

TYPE Locality: Ukhaa Tolgod , Ömnögovi Aimag, Mongolia .

FORMATION: Djadokhta Formation, Campanian ( Dingus et al., 2008), 75–71 Ma ( Dashzeveg et al., 2005)

ETYMOLOGY: Almas is in reference to the wild man or snowman of Mongolian mythology ( Rincen, 1964). Ukhaa refers to the locality of Ukhaa Tolgod, discovered in 1993, where the specimen was collected.

DIAGNOSIS: Almas ukhaa can be referred to troodontids based on the following suite of characters: lacrimal with a prominent supraorbital crest ( fig. 3 ), lacrimal with an anterior process significantly longer than posterior process ( fig. 3 ), numerous dentary and maxillary teeth that are closely packed anteriorly ( figs. 2 , 3 , 4 ), laterally recessed squamosal ( fig. 6 ), and fully arctometatarsalian pes (fig. 15).

Almas ukhaa can be distinguished from all other troodontids by the combination of these derived characters: posteriorly curved pterygoid flange ( fig. 5), absence of a lateral groove on the anterior part of the dentary ( fig. 2 ), distinct spikelike process extending from the anterior edge of the obturator process at the distal one-third of the ischium (fig. 13), the third chevron more than three times as long as the corresponding caudal vertebra ( fig. 10).

Figures

FIGURE 1. Type specimen of Almas ukhaa, IGM 100/1323.

FIGURE 2. Skull of IGM 100/1323 in right lateral view.

FIGURE 3. Skull of IGM 100/1323 in left lateral view.

FIGURE 4. Dentition and rostrum of IGM 100/1323.

FIGURE 6. Left squamosal of IGM 100/1323 in A. posterolateral and B. lateral views.

FIGURE 7. A. Parietal of IGM 100/1323 in ventral view; B. supraoccipital in posterior view.

FIGURE 8. Prootic of IGM 100/1323. Right prootic in A.anterior, C. lateral and E. medial views; left prootic in B. anterior, D. lateral, and F.medial view.

FIGURE 9. Postcranium of IGM 100/1323.