Type D killer whale

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The type D killer whale (Orcinus orca type D) is an ecotype of the killer whale (orcas) occurring in the southern hemisphere . It lives in the sub-Antarctic waters of the Southern Ocean .

Appearance

The type D orca differs from the other types of the killer whale in a few respects.

The melon is much more pronounced, so the head is much rounder. A very noticeable feature is also its greatly reduced eye spot, which is often more than four times as large in the other ecotypes. The dorsal fin of the males is slightly more pointed and more arched than that of the males of the other killer whales. The males reach average sizes of 6–7 m and the females up to 6 m.

discovery

When a whole group of 17 animals of this ecotype stranded in 1955, they were thought to be a group changed by a mutation due to their appearance, which differs greatly from that of the other killer whales in some respects, and their skulls were brought to a museum. After an alleged sighting in 1995 and a few photos that surfaced in 2004, more and more scientists began to be interested in this new type of orca.

In January 2019, some scientists succeeded in filming a group of around 30 individuals off the southern tip of Chile and taking tissue samples.

Systematics

So far, the type D killer whale is considered an ecotype of the species Orcinus orca. The division of all ecotypes into one species, without subspecies, has long been a point of contention among scientists. Genetic studies on the skulls of the animals stranded in 1955 suggest that type D is really a subspecies of its own. Some scientists are even discussing a possible type D species status and subspecies status for some of the other ecotypes. An analysis of the tissue samples taken from 2019 should finally bring clarity, and the eternal question of the internal systematics of the great killer whale and the classification of type D.