A horrifying trapdoor spider measuring more than 20mm in length roamed regional Australia millions of years ago, scientists have discovered.
The spider, named Megamonodontium mccluskyi, was unearthed by a group of scientists working at a renowned fossil site in the NSW Central Tablelands.
At 23mm in length, the spider fossil is the second largest ever discovered and is more than five times the size of its modern-day relatives.
The fossilised arachnid resembles brush-footed trapdoor spiders in western NSW and marks an important discovery for researchers.
UNSW palaeontologist Matthew McCurry said only four spider fossils had been found in Australia, making it difficult to understand their history.
“This discovery is so significant, it reveals new information about the extinction of spiders and fills a gap in our understanding,” he said.
“The closest living relative of this fossil now lives in wet forests in Singapore through to Papua New Guinea.
“This suggests that the group once occupied similar environments in mainland Australia but have gone extinct as Australia became more arid.”
The fossil is dated at being between 11 to 16 million years old and draws its name from the man who unearthed it, Dr Simon McClusky.
Its discovery was the culmination of work by scientists from ANU, UC and UNSW whose findings have since been published,
Queensland Museum arachnologist Robert Raven, the supervising author, said the fossil was the largest ever fossil spider found in Australia.
“(The spider) is the first fossil of the family Barychelidae that has been found worldwide,” Dr Raven said.
“There are around 300 species of brush-footed trapdoor spiders alive today, but they don’t seem to become fossils very often.
“This could be because they spend so much time inside burrows and so aren’t in the right environment to be fossilised.”
The fossil is now housed in the Australian Museum’s palaeontology collection and is available online for researchers to study.
The site where it was unearthed, McGraths Flat, near Gulgong, was also recently found to be the home of a new fossilised jumping spider.