Uintatherium anceps ( Marsh, 1871 )

Murphey, Paul C. & Kelly, Thomas S., 2017, Mammals from the earliest Uintan (middle Eocene) Turtle Bluff Member, Bridger Formation, southwestern Wyoming, USA, Part 2: Apatotheria, Lipotyphla, Carnivoramorpha, Condylartha, Dinocerata, Perissodactyla and Artiodactyla, Palaeontologia Electronica (Cambridge, England: 2003) 20 (2), pp. 1-51 : 29-31

publication ID	https://doi.org/ 10.26879/720
publication LSID	lsid:zoobank.org:pub:341D2FE3-977D-4C82-A337-C681FC00C53A
persistent identifier	https://treatment.plazi.org/id/BB4187B4-FF86-FF99-FC5E-74DFFD42FD59
treatment provided by	Felipe
scientific name	Uintatherium anceps ( Marsh, 1871 )
status

Treatment

Uintatherium anceps ( Marsh, 1871)

Figure 12.1-3 View FIGURE 12 , Table 3

Referred specimens. From DMNH Locality 4673: RP3 or 4, DMNH 75308; Lp2, DMNH 75310; Lm2, DMNH 75309.

Description. Whether the upper premolar is a P3 or 4 cannot be determined because Turnbull (2002) found that these two teeth overlap in dimensions almost completely. The lower molar can be confidently identified as m2 because it fits well within the non-overlapping observed ranges for this tooth position ( Turnbull, 2002).

The P3 or 4 has an oval occlusal outline with an anteroposteriorly compressed V-shaped talon. The paracone is the tallest primary cusp and is connected to the large protocone by a well-developed, tall protoloph. The metacone is compressed anteroposteriorly and connected to the protocone by a moderately strong, tall metaloph. The anterior and posterior cingula are robust. The hypocone is small and positioned on the posterior cingulum below the level of the lingual portion of the metaloph.

The enamel of the p2 is broken off at the anterior most portion of the tooth. It has a short, tall, obliquely orientated metalophid that is connected anterolabially to a weak protoconid and posterolingually to a weak metaconid. The hypoconid is relatively distinct and connected anterolingually to the posterior base of the protoconid by a hypolophid, both of which are about three-quarters the height of the metalophid. The entoconid is small, lower in height than the hypoconid, and connected to the latter by a low cristid.

The m2 exhibits the following characters: 1) an incipient paraconid; 2) a very tall, slender metaconid; 3) a distinct metastylid connected to the metaconid posteriorly; 4) a strong metalophid, connecting the large protoconid to the metaconid and metastylid; 5) a robust hypoconid, hypolophid, and entoconid; 6) a sharply cuspate hypoconulid, positioned at the middle of the posterior margin of the talonid; and 7) weak anterior and labial cingulids.

Remarks. The three teeth from the TBM are indistinguishable from those Uintatherium anceps ( Marsh, 1886; Wheeler, 1961; Lucas and Schoch, 1998; Turnbull, 2002) and are referred to the species. Uintherium anceps is known from the late Bridgerian (Br3) through the early Uintan (Ui2), so its occurrence in the TBM is not surprising.