Vibrassae
are sensory organs found in hippos and baleen whales. Odontocete whales lack such vibrissae.
Figure 1. Mysticete (right whale) vibrissae compared to hippo vibrissae. Odontocete whales lack such structures.
Earlier the large reptile tree (LRT, 1644+ taxa) showed that odontocete members of the traditional clade Cetacea are not related to mysticetes, which arise from a clade of mesonychids, hippos and desmostylians. Odontocetes arise from tenrecs.
