Two venomous Australian spiders thought to be distantly related are actually close relatives, the International Business Times reports.
Based on their physical attributes, scientists had placed the Sydney funnel-web spiders and eastern Australian mouse spiders on branches of the spider family tree that diverged about 200 million years ago, it adds. But, IBT notes that the venom of the two species argued for a closer relationship — the same anti-venom is used to treat both funnel-web and mouse spider bites.
An international team of researchers has sequenced spiders belonging to genera within both the Hexathelidae and Actinopodidae families, including some rare museum specimens. The team's phylogenetic analysis appearing in Scientific Reports found that hexathelids aren't monophyletic and that atracines — which include the Sydney funnel-web spider — are sister to actinopodids.
"The funnel-webs always were an uncomfortable fit in their taxonomic place," first author Marshal Hedin from San Diego State University says in a statement. "I could see the writing on the wall."
IBT adds that knowing how venomous spiders evolved could not only help treat people who are bitten but also aid in developing insecticides.