FIGURE 1. Map of Mongolia, showing the location of the working area in the Valley of Lakes (Modified from Map of Mongolia by Cartography Co. Ltd, Ulan Bator, Mongolia).

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FIGURE 2. Dental terminology of the upper and lower cheek teeth of Yindirtemys deflexus. Terminology after Vianey-Liaud et al. (2006) and Wang (1997). Illustration modified from Schmidt-Kittler et al. (2007).

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FIGURE 3. Stratigraphic ranges of the Yindirtemys species from the Valley of Lakes (Mongolia). Stratigraphic chart (modified from Daxner-Höck et al., 2015) including the geological time scale (Gradstein et al., 2004), basalt ages and Mongolian biozones A - D (Höck et al., 1999), the lower boundary of the Xiejian Chinese Mammal Age after Meng et al. (2006).

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FIGURE 4. Upper molars of Yindirtemys deflexus from the Valley of Lakes (Mongolia). Nos. 1-18. From Loh: 1) LOH-C/1-NHMW 2006./0083/0002 P4-M3 left; 2) LOH-C/1-NHMW 2006/0083/0007 M3 right. From Del: 3) DEL-B/12-NHMW 2006/0089/0006 M2 right; 4) DEL-B/12-NHMW 2006/0089/0033 M1 left. From Huch Teeg: 5) RHN-A/7-NHMW 2006/0090/0009 M3 right; 6) RHN-A/7-NHMW 2006/0090/0010 M3 left; 7) RHN-A/7-NHMW 2006/0090/0012 M3 left; 8) RHN-A/7-NHMW 2006/0090/0015 DP4 right; 9) RHN-A/7-NHMW 2006/0090/0039 P4 left; 10) RHN-A/7-NHMW 2006/0090/0045 P4 right; 11) RHN-A/7-NHMW 2006/0090/0047 P4 right; 12) RHN-A/7-NHMW 2006/0090/0052 M3 right; 13) RHN-A/7-NHMW 2006/0090/0053 M2 right. From Toglorhoi: 14) TGW-A/surface -NHMW 2006/0086/0005 Complete maxilla. From Tatal Gol: 15) TAT-043-NHMW 2012/0034/0005 M2-M3 right. From Huch Teeg: 16) RHN-023-NHMW 2012/0038/0014 M1 right. From Hotuliin Teeg: 17) HTSE-009+013-NHMW 2012/0039/0015 M2-M3 right; 18) HTE-057-NHMW 2012/0045/0002 DP4 left. All teeth same magnification. Scale bar equals 1 mm.

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FIGURE 5. Lower molars of Yindirtemys deflexus from the Valley of Lakes (Mongolia). Nos. 1-21. From Loh: 1) LOH-C/1-NHMW 2006/0083/0015 dp4 right. From Ikh Argalatyn Nuru: 2) IKH-A/5-NHMW 2009/0148/0011 m1 left. From Del: 3) DEL-B/12-NHMW 2006/0089/0001 m2-m3 left; 4) DEL-B/12-NHMW 2006/0089/0002 m3 right; 5) DEL-B/12-NHMW 2006/0089/0018 p4 right; 6) DEL-B/12-NHMW 2006./0089/0025 m2 left; 7) DEL-B/12-NHMW 2006/0089/00027 m3 left; 8) DEL-B/12-NHMW 2006/0089/0029 m3 left; 9) DEL-B/12-NHMW 2006/0089/0041 m3 right. From Huch Teeg: 10) RHN-A/7-NHMW 2006/0090/0001 p4-m3 left; 11) RHN-A/7-NHMW 2006/0090/0004 dp4 left; 12) RHN-A/7-NHMW 2006/0090/0005 p4 left; 13) RHN-A/7-NHMW 2006/0090/0019 p4 right; 14) RHN-A/7-NHMW 2006/0090/0021 dp4 right; 15) RHN-A/7- NHMW 2006/0090/0031 m2 right; 16) RHN-A/7- NHMW 2006/0090/0032 m3 right; 17) RHN-A/7-NHMW 2006/0090/0037 m2-m3 left. From Tatal Gol: 18) TAT-051/2-NHMW 2012/0035/0005 m1 right. From Huch Teeg: 19) RHN-023-NHMW 2012/0038/0023 m2 left; 20) RHN-023-NHMW 2012/0038/0027 m1 right. From Hotuliin Teeg: 21) HTSE-009+013-NHMW 2012/0039/0020 m1 left. All teeth same magnification. Scale bar: 1 mm.

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FIGURE 6. Yindirtemys suni from the Valley of Lakes (Mongolia). Nos. 1-12. From Hotuliin Teeg (south): 1) HTS-056/3-NHMW 2012/0047/0001 M2-M3 right. From Unkheltseg: 2) UNCH-A/4-NHMW 2006/0088/0001 dp4 right; 3) UNCH-A/4-NHMW 2006/0088/0003 M1 left. From Hotuliin Teeg (east): 4) HTE-009-NHMW2012/0033/0009 m3 left; 5) HTE-008-NHMW 2012/0032/0004 p4 right; 6) HTE-008-NHMW 2012/0032/0005 m2 right; 7) HTE-008-NHMW 2012/0032/0006 m3 left; 8) HTE-014-018-NHMW 2012/0031/0001 P4-M2 right; 9) HTE-014-018-NHMW 2012/0031/0002 M2 right; 10) HTE-014-018-NHMW 2012/0031/0003 M3 right; 11) HTE-014-018-NHMW 2012/0031/0006 M3 left; 12) HTE-014-018-NHMW 2012/0031/0009 m1-m3 left. All teeth same magnification. Scale bar equals 1 mm.

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FIGURE 7. Complete maxilla of Yindirtemys birgeri from the locality of Tatal Gol (TAT-051/2- NHMW 2012/0060/0001) in the Valley of Lakes (Mongolia). Nos. 1-8. 1) P4 left; 2) M1 left; 3) M2 left; 4) M3 left; 5) P4 right; 6) M1 right; 7) M2 right; 8) M3 right. All teeth same magnification. Scale bar equals 1 mm.

 

 

FIGURE 8. Distribution of the length and width ranges charts of the upper and lower dental elements for the three large-sized species of Yindirtemys from the Valley of Lakes.

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