Orcinus citoniensis is an extinct species of orca identified in the Late Pliocene of Italy and the Early Pleistocene of England.

O. citoniensis could have hunted fish and squid in pods, and coexisted with other large predators of the time such as the orcinine Hemisyntrachelus and the extinct shark Otodus megalodon.

[3] Bianucci further identified a beak fragment showing tooth sockets, also from the Late Pliocene of Tuscany, which may belong to the species.

Concerning diet, it may have been more similar to the modern false killer whale (Pseudorca crassidens) and pygmy killer whale (Feresa attenuata), mesopredators of squid and large fish,[11][12] but given the comparative gracility of the teeth, it may have only been capable of catching small- to medium-sized fish (though it was still probably capable of biting and tearing into a large prey creature).

[13] The Pliocene of Tuscany is representative of a nutrient-rich upwelling in coastal waters and the upper midnight zone along a continental slope.

Seagrasses may have been common, similar to the modern day meadows of neptune grass (Posidonia oceanica) that occur in the region.

[16] The Red Crag Formation is representative of a temperate, shallow nearshore environment, perhaps at the mouth of a large river indicated by conifer pollen and small terrestrial vertebrate remains.