Scientists in Australia reported that the world’s oldest known spider, a female Giaus Villosus or trapdoor spider, recently died during a long-term population study. The poisonous creature, named Number 16 was 43 years old and had outlived the world’s next-oldest spider, a tarantula in Mexico, by a whopping 15 years.

Number 16 was included in the population targeted for the study right after birth in 1974. The work, conducted in Western Australia’s Central Wheatbelt region, was aimed at observing trapdoor spiders and understanding how they managed to live for so long.

“To our knowledge, this is the oldest spider ever recorded, and her significant life has allowed us to further investigate the trapdoor spider’s behavior and population dynamics,” Leanda Mason, one of the authors studying the spiders, said in a statement.

During the observation, they noted the secret to trapdoor spiders’ longevity lies in their sedentary way of living. They build nearly 30-centimeter-deep burrows with a cork-like trapdoor made of soil and vegetation, and sit inactive with low metabolism in those tiny, plant and soil camouflaged homes.

This keeps them from expending unnecessary energy and contributes towards extending their life, something scientists believed helped Number 16 live this long.

The study on the tiny, eight-legged creature was started by Barbara York Main, a biologist specializing in the study of spiders, and later taken over by the researchers at the Curtin University, Australia.

“Through Barbara’s detailed research, we were able to determine that the extensive lifespan of the trapdoor spider is due to their life-history traits, including how they live in uncleared, native bushland, their sedentary nature, and low metabolisms,” Mason added. The researcher expressed grief about the demise of the creature and told the Telegraph she wanted to it complete at least 50.

The group believes studying these spiders not only gives insight into their unique way of long-living but can also help them understand how the species will behave when global-warming and habitat change takes a toll on them. “These spiders exemplify an approach to life in ancient landscapes, and through our ongoing research we will be able to determine how the future stresses of climate change and deforestation will potentially impact the species,” study co-author Wardell-Johnson said.

Typically, Trapdoor spiders are around 2-3 centimeters long, with powerful jaws and sharp fangs. The creatures use their trapdoor burrows for the purpose of catching prey at night. Female trapdoor spiders do not venture too far away from their burrows and use it as a way to protect their eggs until they hatch.

The report on the oldest spider was detailed in a paper titled, "The longest-lived spider: mygalomorphs dig deep, and persevere," and published in the Pacific Conservation Biology Journal on April 27.