Table 2.

Measurements of holotypic dorsal vertebrae of A. altus (AMNH FARB 5764). DvA, middle–posterior dorsal vertebra; DvB, posterior dorsal vertebra. Measurements in millimetres.

dimension	DvA	DvB
anteroposterior length of centrum	∼220	242
dorsoventral height of anterior end of centrum	—	251
dorsoventral height of posterior end of centrum	∼274	266
mediolateral width of posterior end of centrum	∼231	258
dorsoventral height of neural arch	∼239	212
dorsoventral height of neural spine	—	620
anteroposterior length of neural spine (near base)	—	158
mediolateral width of neural spine (near base)	—	72
maximum mediolateral width of neural spine (near apex)	—	148
distance from midline to lateral tip of diapophysis	—	303
dorsoventral height at lateral tip of diapophysis	—	111