Figure 2.

Teeth of H. subathuensis holotype compared with those of pakicetid Pakicetus attocki and Pakicetus inachus. All teeth are shown in occlusal (Upper) and lateral (Lower) view; anterior is toward the left in all drawings. (a) Crown of left M₂ of H. subathuensis, RUSB 2003. (b) Crown of left M₃ of H. subathuensis, RUSB 2003. (c) Crown of left M₂ of P. attocki (reversed), Howard University–Geological Survey of Pakistan H-GSP 18410 (7). (d) Crown of left M₃ of P. inachus, GSP-UM 82 (8). Note the general similarity of molar form seen in Himalayacetus and Pakicetus. The sulcus on the anterior face of the trigonid is found in all archaeocetes. Differences distinguishing Himalayacetus include a larger and more rounded major cusp (protoconid), a smaller and less elevated talonid cusp (hypoconid) on the talonid, and a more anteriorly projecting anteromedial cusp at the base of the trigonid.