Tasmacetus

About Tasmacetus

Every other beaked whale has reduced its dentition to a tusk or two in the males. Tasmacetus has not: it carries roughly seventeen to twenty-one pairs of functional teeth in the upper jaw and eighteen to twenty-eight in the lower, in addition to the enlarged apical pair that males of the family typically erupt. That retention makes it the most primitive-looking living member of the family and a key point of reference for how the rest of the group lost its teeth.

It is circumpolar in cool temperate waters of the Southern Hemisphere and very seldom encountered. Confirmed at-sea sightings number in the low dozens; the species was described in 1937 from a stranding in New Zealand and was not photographed alive until the twenty-first century.