A lamprey fish has been found living in the coastal rivers of Queensland, Australia, about 1,400 km north of the species’ usual range.
Lampreys are fish which recall a time hundreds of millions of years ago. Unlike most fish today, lampreys are jawless. Jaws evolved in fish more than 400 million years ago. Research suggests the development of jaws was vital in some pioneering species making the move onto land, becoming the ancestors of all land vertebrates like humans.
Australian brook lampreys (Mordacia praecox) are an endangered species. Their range was widely believed to be restricted to a 170-km stretch of coastline near the border of Australian states Victoria and New South Wales (NSW).
But individuals have now been found much further north, in the streams of Queensland.
Griffith University ecologist Luke Carpenter-Bundhoo discovered Australian brook lampreys living in streams on Fraser Island (K’gari), more than 200 km north of the state capital Brisbane.
Aware of the significance of his discovery, Carpenter-Bundhoo teamed up with David Moffat, an ecologist with Queensland’s Department of Environment and Science.
The aquatic ecologists confirmed lamprey sightings in Queensland, including as far north as Rockhampton, more than 500 km northwest of Brisbane.
Their findings are presented in a paper published in the journal Endangered Species Research.
“It’s quite exciting to find an endangered species so far out of its known range, yet so close to populated areas,” says Moffatt. “We expect these animals naturally occur in Queensland, and have been here for an awfully long time, but have remained hidden due to their cryptic nature.”
The Australian brook lamprey is usually about 15 cm long. Its jawless mouth is filled with rows of sharp teeth. Unlike most other species of lamprey, however, it doesn’t suck on blood. This non-parasitic species spends its first 3 years as a larva filter feeding while buried in the bottom of streams. Once it reaches adulthood, it lives for another year to breed, not feeding at all.
It is thought to be extinct where it was first described in southern NSW.
The species is threatened by sedimentation, wildfires and human development. But another major threat is the animal is very difficult to identify. For most of the creature’s life, it is virtually indistinguishable from the more common, blood-sucking short-headed lamprey (Mordacia mordax) which is widespread in southeastern Australia.
An additional threat to the brook lamprey is the danger of sea level rise from global climate change.
The scientists hope that their new findings in Queensland will help the conservation of these threatened “living fossils.”