Deloraine brothers Jarom and Levi Triffitt said they stumbled among the skull while seeking fresh water lobsters on Friday.

However their hopes were dashed when collections officers at the Queen Victoria Museum and Art Gallery deemed it a dog skull this morning.

Nevertheless the duo's efforts were praised by QVMAG staff who said the ''very remote'' chance of finding the skull of an extinct thylacine was worth pursuing.

The last thylacine skull discovered in the wilderness occurred prior to the death of the animal's eradication in 1936.

EARLIER

DELORAINE brothers Levi and Jarom Triffitt may have found a Thylacine skull.

The Thylacine, commonly known as the Tasmanian Tiger, was declared extinct in 1986, 50 years after the last captive Thylacine died in Hobart Zoo.

The brothers, who started extreme sports group, Tassie Boys, were trail riding in a remote area of Northern Tasmania when they stumbled across the skull.

"We started our day trail riding as usual, stopped for a short break and went for a walk to see if we could find a fresh water lobster in the creek and ended finding a skull,'' the brothers posted on their website.

''We weren't real sure what it was at first but by the look of the long bottom jaw and teeth we knew it couldn't have been a wallaby or possum and were convinced it was a tasmanian tiger.''

The skull is being evaluated at the Queen Victoria Museum and Art Gallery today.