SYDNEY -- An 81-year-old midnight snapper (Macolor macularis) living off the coast of Western Australia (WA) had been confirmed as the world's oldest tropical reef fish on record after checking all age-related research published in the scientific literature, Australian researchers said Tuesday.

The research, led by Brett Taylor from Australian Institute of Marine Science (AIMS), had found the octogenarian fish at the Rowley Shoals off WA's north-west coast, where they also identified a 79-year-old red bass (Lutjanus bohar).

In the study, researchers sampled the age of three fish species not targeted by local fishing from four locations along the tropical coast in WA, as well as the protected Chagos Archipelago in the central Indian Ocean and provided a revised understanding of the longevity of tropical fish.

"Until now, the oldest fish that we've found in shallow, tropical waters have been around 60 years old," Taylor said.

"We've identified two different species here that are becoming octogenarians, and probably older."

Researchers were able to accurately determine the age of a fish by counting the annual growth bands of fish's ear bone, in much the same way as counting tree rings and had identified 11 fish individuals older than 60.

The results will also help researchers understand how the fish's length and age will be affected by climate change, according to Taylor.

"We're observing fish at different latitudes-with varying water temperatures-to better understand how they might react when temperatures warm everywhere," he said.