Meet the giant wood moth — the heaviest moth in the world.

Insects in Australia tend to be surprisingly large, from pug-sized spiders to stick insects bigger than your hand, but when a female giant wood moth showed up at a Queensland school, she surprised everyone.

“We have a range of animals on our grounds at Mount Cotton State School, such as bush turkeys, wallabies, koalas, ducks, the occasional snake that needs to be relocated back to our rainforest, echidnas, tree frogs, possums, chickens and turtles,” Meagan Steward, the school’s principal, told The Dodo in a statement. “But a giant wood moth was not something we had seen before.”

Construction workers spotted the moth while working on a classroom addition at the edge of the rainforest. Female wood moths can have a wingspan up to 10 inches and weigh as much as two finches, according to the Queensland Museum. The weight of this giant insect is partially due to the 20,000 eggs she carries and deposits in the bark of trees.

According to Dr. Christine Lambkin, head of entomology at the Queensland Museum, these heavy moths have difficulty flying and tend to just crawl up trees and wait for the males, who are half their size.

After the construction crew snapped a few photos of the giant fuzzy moth, she was returned to a tree in the nearby rainforest, where she could wait for a mate to find her.