By ANNE BESTON
A "dinosaur in miniature", the largest beetle of its type, has entered the scientific record books but the mystery of its extinction may never be solved.
The wrinkled fungus beetle grew to the length of a man's thumb and, with moa, raptors and large weta, was part of
New Zealand's "mega-fauna" that existed thousands of years ago.
With its brown, warty body covered in patches of bristles and a crust of waxy secretions, Archaeophylax worthyi provides palaeontologists and entomologists with a tantalising glimpse of early New Zealand.
"As an entomologist you would have loved being around 2000 years ago," Landcare Research scientist Dr Richard Leschen said.
"The fact this beetle was once in our backyard and we know so little about it or why it went extinct is fascinating."
While some examples of pre-historic insects have survived, such as the common weta, it was a mystery why others did not make it, he said.
"The common weta is a big animal so maybe there was something in this beetle's behaviour that allowed it to disappear."
The new genus and species of beetle was named after palaeontologist Trevor Worthy, who discovered its fossil in a Waitomo cave. It is the first reported case of gigantism in fungus-feeding beetles.
Dr Leschen said that because so many large, flightless insects went extinct after the kiore or Polynesian rat was introduced, many scientists believed introduced non-native predators were to blame for the disappearance of mega-fauna species.
The fact large-bodied beetles, and other insects such as the giant tusked weta, still survived on islands supported that theory, he said.
"As more fossils are discovered, it becomes patently apparent that New Zealand was a land of giants and Archaeophylax worthyi is probably one of hundreds of extinct insects that once truly walked with the dinosaurs."
At the other end of the scale, New Zealand scientists have been part of an international team studying a tiny spider that is the largest land animal in Antarctica's Ross Sea region.
New Zealand scientist Dr Brent Sinclair was part of team who spent 11 weeks weathering temperatures as low as minus 20C to study the 2mm-long springtail spider at Cape Hallett, 600km north of Scott Base.
"It can survive temperatures below minus 30C by utilising anti-freezes to keep body fluids liquid," Dr Sinclair said. "They are capable of running around when their body temperature is as low as minus 10C."
The team hoped its spider data would help scientists understand the mechanisms that limited distribution of plants and animals.
"If we know why any species has a distribution limit that allows us to predict how species respond to changes in their environment," Dr Sinclair said.
The springtail spider is named after the spring-like organ on its abdomen - the furcula - that allows it to jump.
www.landcareresearch.co.nz/
Herald feature: Environment
By ANNE BESTON
A "dinosaur in miniature", the largest beetle of its type, has entered the scientific record books but the mystery of its extinction may never be solved.
The wrinkled fungus beetle grew to the length of a man's thumb and, with moa, raptors and large weta, was part of
AdvertisementAdvertise with NZME.