is a fossil whale that was found in the limestone of Jan Juc beach near Torquay, Victoria. The genus name comes from the location it was found and the species name was named after the teenager who discovered it, Stuamn Hunder.
The fossil skull (P 216929) is around 25 million years old and exceptionally preserved. Janjucetus
is an early baleen whale, the group of whales that includes the Blue Whale. Today, baleen whales lack teeth and feed by filtering small food items out of large volumes of water using the baleen (long bristly plates made out of keratin) in their mouths. While the name baleen whale suggests that every species in this group must have baleen, what makes a baleen whale a baleen whale are other anatomical features shared by the group. Unlike modern baleen whales Janjucetus
had large teeth and was an active, voracious predator rather than a filter feeder.
Instead of plates of baleen Janjucetus
had conical incisors and canines. The shape, placement and orientation of the incisor and canine teeth in the broad, short snout are similar to those of modern aquatic animals that eat fish and other small vertebrates. The shape of the skull and its muscle attachments show that it would have had a very strong bite, allowing it to tear its prey into pieces it could swallow. It also had cheek teeth that were serrated, almost leaf-like in shape, which would have been used for shearing through flesh. The shape and structure of the skull bones also suggests Janjucetus
might have been able to feed by suction.
At only three metres long Janjucetus
was also much smaller than modern baleen whales. It had unusually large eyes which it probably relied on rather than being able to echolocate.
The museum's skull of Janjucetus hunderi
is the only one known of this species but Janjucetus
isn't the only toothed baleen whale, there are several others known from the fossil record. Some early baleen whales may have had a mix of teeth and baleen, while some would only have had baleen and others like Janjucetus
had no baleen at all. Janjucetus
is important because it shows a previously unknown stage in the early evolution of the baleen whales.
is one of eight candidates for Victoria's fossil emblem.