[9] The published names for the genus and their relationship to other delphinids combined epithets such as orca, grampus, gladiator and orcinus throughout the nineteenth century.

[10] The beaching of whales in Eastern Australia (a female and male Grampus griseus) prompted a taxonomic revision in 1933, the authors Tom Iredale and Ellis Troughton proposed that the extensive use of "Grampus" be conserved as the generic name of orca (Orcinus orca) and that a new genus named Grampidelphis be established for Rissos dolphin (Grampus); the general stability of current species names emerged after the publication of the Philip Hershkovitz's Catalog of Living Whales (US National Museum, 1966).

The existing population, known as orca or killer whale, are a well known apex predator readily distinguished by their great size, 7 to 10 metres long, and mostly black and white coloring.

Distinctions within the living Orcinus population are often observed in unique social behaviours, their cultures, which provided a significant evolutionary advantage in moving from a diet of cephlapods and fish to other mammals.

[14] Fossil evidence of Orcinus species occur in a temporal range of 3.6 million years ago until the present day.

The most ancient species Orcinus meyeri refers to fossils of a partial jaw and teeth located at the early Miocene horizon of a site near Stockach in Germany.