Omura's whale has only recently been described and classified as a separate species. Prior to 2003, the Omura's whale was previously and incorrectly thought to be a pygmy form of the Bryde's whale. To date, only a dozen or so specimens have been genetically confirmed to be Omura's whales and therefore information is lacking on all aspects of this species.
A slender bodied whale, smaller than Bryde's, sei, fin and minke whales, it is thought to differ in body shape from other baleen whales but similar in colouration to fin whales including an assymetrical lower jaw – white on the right-hand side, dark on the left. Similarly to the sei whale, the Omura's whale has one prominent ridge on the rostrum, although there may also be accessory ridges. The 80 – 90 throat pleats extend well beyond the navel. It is thought that the dorsal fin is tall and falcate, set about two-thirds of the way back on the body. The flippers are relatively long and pointed and the flukes are broad with an indistinct notch and straight trailing edge. As the external appearance of the Omura's whale has not yet been adequately described it would be easy to confuse this species with other small to medium sized baleen whales.
Next to nothing is known about the behaviour of Omura's whales although from the few confirmed sightings they are thought to be found as solitary individuals or in pairs. From the presence of throat grooves it is known that like other rorquals, Omura's whales are lunge feeders and probably feed predominantly on schooling fish.
The exact range of Omura's whale has not been established although they are thought to be confined to the subtropical waters of the western Pacific and Indian Oceans including the nearshore, continental shelf waters of the Solomon Sea, the Philippines, Indonesia and Southern Japan. In recent times, Omura's whales have been hunted during Japanese scientific whaling and Philippine artisanal hunts. Other human-induced threats include habitat modification, bycatch and anthropogenic noise. No global population estimate exists for this species and the IUCN lists Omura's whale as 'Data Deficient'.