Raoellidae

Raoellidae Temporal range: 56–41.3 Ma PreꞒ Ꞓ O S D C P T J K Pg N Early Eocene – Middle Eocene[1]
Indohyus
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Clade:	Cetaceamorpha
Family:	†Raoellidae Sahni, Bal Bhatia, Hartenberger, Jaeger, Kumar, Sudre & Vianey-Liaud, 1981
Genera
Haqueina Dehm & Oettingen-Spielberg 1958 Indohyus Rao 1971 Khirtharia Pilgrim 1940 Kunmunella Sahni & Khare 1971 Raoella Sahni & Khare 1971 Metkatius Kumar & Sahni 1985

The Raoellidae, previously grouped within Helohyidae, are an extinct family of semiaquatic digitigrade artiodactyls in the clade Whippomorpha. Fossils of raoellids are found in Eocene strata of South Asia and Southeast Asia.

An exceptionally complete skeleton of Indohyus from Kashmir suggests that raoellids are the "missing link" sister group to whales (Cetacea).^[2] All other Artiodactyla are relatives of these two groups. δO¹⁸ values and osteosclerotic bones indicate that the raccoon-like Indohyus was habitually aquatic. However, it is still unclear if Indohyus primarily fed on land or in water. It is hypothesized that cetaceans evolved from ancestors similar to Indohyus and later fully adapted to aquatic life.