TABLE 1. Megafauna and fossil pollen taxa identified in the locality Las Tazas.
| Mammals | Pollen | ||||
| Order | Family | Species | Order | Family | Genus |
| Xenarthra | Pampatheriidae | Pampatherium mexicanum | Pinales | Pinaceae | Pinus |
| Perissodactyla | Equidae | Equus conversidens, Equus sp. | Fagales | Fagaceae | Quercus |
| Artiodactyla | Bovidae | Bison sp. | |||
| Camelidae | Camelops hesternus | ||||
| Proboscidea | Elephantidae | Mammuthus columbi | |||
TABLE 2. M2 and M3 measurements in fossil Equus conversidens found in Las Tazas locality (BUAPAL) compared with other species of Equus and Haringtonhippus reported in Mexico by Priego-Vargas et al. (2017). All measurements are in millimeters.
| Species | Anteroposterior length | Transverse width | ||||
| Mean | Min-Max | N | Mean | Min-Max | N | |
| M2 | ||||||
| BUAPAL 773 | -- | 24.6 | 1 | -- | 23.81 | 1 |
| E. mexicanus | 29.65 | 26.35-31.50 | 6 | 28.18 | 25.80-31.40 | 6 |
| E. conversidens | 22.75 | 20.50-25.80 | 32 | 22.54 | 19.79-24.20 | 32 |
| H. francisci | 19.55 | 18.10-20.50 | 4 | 18.28 | 16.37-20.00 | 4 |
| M3 | ||||||
| BUAPAL 774 | -- | 24.33 | 1 | -- | 19.31 | 1 |
| E. mexicanus | 31.35 | 27.5-36.33 | 6 | 24.89 | 23.30-27.80 | 6 |
| E. conversidens | 23.85 | 21.50-27.45 | 32 | 19.51 | 17.10-23.70 | 32 |
| H. francisci | 22.45 | 21.60-23.05 | 3 | 15.53 | 14.00-17.30 | 3 |
TABLE 3. Measurements of the p2-p4 premolars of Equus spp. and the sum of their means (taken from Table 3, Priego-Vargas et al., 2017).
| Species | Anteroposterior length of pm 2-3 | ||
| M2 | Mean | Min-Max | N |
| BUAPAL 773 | -- | 100.00 | 1 |
| E. mexicanus | 101.1 | 94.90-105.00 | 13 |
| E. conversidens | 84.0 | 77.30-91.40 | 18 |
| H. francisci | 71.7 | 70.10-71.70 | 4 |
TABLE 4. Cranial measurements comparison between the fossil material from Las Tazas, Valsequillo (BUAPAL) and the Bison species reported by McDonald (1981) and Skinner and Kaisen (1947). LTPP = total length of the horn cores from end to end, DVCC = vertical diameter of the horn cores and their circumference, LRC = relative length of the horn core, ACO = width between the occipital condyles. All measurements are in millimeters.
| Species | LTPP | DVCC | LRC | |||
| Min-Max | N | Min-Max | N | Min-Max | N | |
| BUAPAL 755 | 700 | 1 | 100 | 1 | 200 | 1 |
| B. antiquus | 765-1067 | 27 | 81-126 | 27 | 203-364 | 27 |
| B. occidentalis | 626-1055 | 77 | 70-114 | 85 | 186-392 | 86 |
| B. bison | 510-778 | 128 | 69-99 | 139 | 124-270 | 134 |
| B. latifrons | 1445-2235 | 19 | 107-178 | 34 | 551-1090 | 25 |
| B. athabascae | 542-848 | 9 | 81-106 | 9 | 165-323 | 9 |
| B. priscus | 751-1064 | 23 | 84-116 | 52 | 285-416 | 36 |
| B. alaskensis | 800-1540 | 25 | 100-153 | 49 | 426-795 | 36 |
TABLE 5. Metacarpal measurements comparison between the fossil material from Las Tazas, Valsequillo (BUAPAL) and the Bison species reported by McDonald (1981) and Skinner and Kaisen (1947). L = total length of bone, AP = Antero-posterior minimum of diaphysis, TRtr = Transverse minimum of diaphysis. All measurements are in millimeters.
| Species | L | AP | TRtr | |||
| Min-Max | N | Min-Max | N | Min-Max | N | |
| BUAPAL | 207 | 1 | 27 | 1 | 44 | 1 |
| B. antiquus | 211-238 | 28 | 28-33 | 28 | 47-61 | 28 |
| B. occidentalis | 248-300 | 150 | 29-38 | 161 | 32-48 | 156 |
| B. bison | 232-276 | 118 | 27-34 | 115 | 30-34 | 115 |
| B. latifrons | 270-281 | 3 | 32-34 | 3 | 38-41 | 3 |
| B. athabascae | 256-279 | 4 | 30-35 | 5 | 34-39 | 5 |
TABLE 6. Calcaneal measurements comparison between the fossil material from Las Tazas, Valsequillo (BUAPAL) and the Camelidae species reported by Guérin and Faure (1999) measurements are in millimeters.
| Species | Maximun length | Maximun anteroposterior length |
Tuber transverse width |
Tuber anteroposterior width |
||||
| Min-Max | N | Min-Max | N | Min-Max | N | Min-Max | N | |
| BUAP 757 | 168 | 1 | 67 | 1 | 35 | 1 | 54 | 1 |
| C. hesternus | 157.0-170.0 | 13 | 65.0-76.7 | 13 | 40.5-53.2 | 13 | 56.4-65.3 | 13 |
| H. cf. H. macrocephala | 122.6-125.6 | 12 | 52.3-53.7 | 12 | -- | -- | -- | -- |
| Palaeolama major | 103.0-116.5 | 12 | 30.5-35.5 | 4 | 24.5-28.0 | 7 | 33.0-39.5 | 7 |
