Duangkrayom et al.—The first Neogene record of Zygolophodon in Thailand
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Figure 4. The upper third molar of Zygolophodon sp. from Tha Chang sand pit no. 10, PRY200: (1) occlusal view, (2) lingual view, (3) buccal view. M3, PRY200. This upper left molar has four lophs, in
addition to anterior and posterior cingula. The lingual cingulum is quite strong, and the buccal cingulum is only evident in the vicinity of the first valley. The crowns of the first and second lophs are deeply worn, and the third loph is also somewhat worn. The crescentoids are present in the pretrite side and arranged in straight lines that run perpendicular to the
anteroposterior axis of the crown, and appear to be yoke–like in this molar. The first and second lophs bear clear zygodont crests. The pretrite and posttrite half lophs are separated by a strong median sulcus. The molar is wider anteriorly than posteriorly. In lateral view, the posterior pretrite crescentoid of the first loph (pcr1) is well-developed and extends downward to the base of the adjacent valley, where it joins the anterior pretrite
