The group has also uncovered a population of an ancient arachnid known as the Assassin spider.
The spiders were found at a number of sites along a 70 kilometre stretch of coastline near Albany.
The Assassin spider is just five millimetres in length and, despite its name, is harmless to humans.
He says it is a significant discovery.
"We hadn't seen that species for about 25 years, so to find them quite happy in their habitat on the south coast was quite a boon for us," he said.
The new species of spider, which is yet to be named, is about four millimetres long and was discovered at Bremer Bay.
Le saucey sauce
Previous posts about Assassin spiders (not this particular new species though)