FIGURE 1. Index map of collection areas (left) and correlation and dating (right) of the major mammal fossil localities of the Eocene of Trans-Pecos Texas. Magnetic stratigraphy of Testarmata and Gose (1979), Walton (1992), and Prothero (1996) and its correlation with the global magnetic polarity time scale. Location of the important mammalian local faunas (l.f.) and volcanic ash dates are shown. Diagonal cross-hachured pattern denotes sections of indeterminate polarity. Normal polarity is in black, reversed polarity is in white. Abbreviations: BRID. = Bridgerian; BR = Bracks Rhyolite; BU = Buckshot Ignimbrite; GB = Gill Breccia; MMR = Mitchell Mesa Rhyolite; MPTS = magnetic polarity; NALMA = North American land mammal age. (map after Wilson, 1978; correlation after Prothero, 1996).
FIGURE 2. Strict consensus tree for infratribe Brontotheriita based on a parsimony search with implied weighting (k=7). Ovals represent stratigraphic distribution in North American Land Mammal Ages. The ages of Asian species with question marks are approximations based on Asian Land Mammal Age equivalence.
FIGURE 3. (A) The holotype of Protitanops curryi Stock 1936 (LACM/CIT 1854) and (B) a stratigraphically associated but larger specimen previously referred to as Menodontine (?) by Stock (1936) that is possibly P. curryi (LACM/CIT 2007).
FIGURE 4. A skull (FMNH PM 157) from the Blue Cliff Horizon of the Chambers Tuff Formation referred to Protitanops curryi: (A) right view, (B) dorsal view, (C) ventral view, (D) anterior view, (E) posterior view.
FIGURE 5. A juvenile skull (TMM 41916-14) from the “titanothere quarry” of the Lower Chisos Formation referred to Protitanops curryi.
FIGURE 6. A juvenile skull (TMM 41916-8) from the “titanothere quarry” of the Lower Chisos Formation referred to Protitanops curryi: (A) left view, (B) dorsal view, (C) ventral view, (D) mandible.
FIGURE 7. A skull (TMM 41916-6) from the “titanothere quarry” of the Lower Chisos Formation referred to Protitanops curryi: (A) left view, (B) dorsal view, (C) ventral view, (D) posterior view, (E) left P1-P4, (F) anterior dentition, (G) left M1-M3.
FIGURE 8. A skull (TMM 40932-1) from the Lower Chisos Formation previously referred to Menodus bakeri by Wilson (1977a), now referred to Protitanops curryi: (A) dorsal view, (B) left view, (C) anterior view, (D) left P2-P4.
FIGURE 9. A partial skull (IGM 65-29) from the Prietos Formation previously referred to ? Brontops cf. brachycephalus by Ferrusquia-Villifranca (1967), now referred to Protitanops curryi: (A) right view, (B) ventral view, (C) dorsal view. (The number 41017-1 written on the figured specimen is the catalog number of the cast in the TMM collection.)
FIGURE 10. A mandible (TMM 45805-1) from the Big Red Horizon of the Chambers Tuff referred to Protitanops curryi: (A) left view, (B) dorsal view, (C) occlusal view of anterior dentition (D) labial view of anterior dentition.
FIGURE 11. Specimens of Brontotheriita of uncertain generic and specific identify from the Skyline Channels, Devil’s Graveyard Formation, Aqua Fria-Green Valley Area of Trans Pecos Texas: (A, B, C) TMM 41853-17, (D, E, F) TMM 41580-30, (G) TMM 41715-6, (H) TMM 42254-2.
FIGURE 12. Size distributions for ventral skull length, upper molar row length, and lower molar row length for Protitanops curryi and closely related brontotheriids.