A Tasmanian scientist has discovered a new species of jellyfish.

Dr Lisa-ann Gershwin discovered the 13-centimetre long creatures near the Stanley Jetty in the state's north-west at the weekend.

Dr Gershwin is the Curator of Natural Science at the Queen Victoria Museum and Art Gallery in Launceston.

She made the discovery while taking time out from a geology field trip.

The pale orange jellyfish are about the size of an apple and do not sting.

An initial examination indicates they belong to the genus of Leucothea.

She now has the job of classifying it.

"Studying these jellyfish can help us understand how they survive for such long periods of time as well as how they may respond to climate change in the future," she said.

Dr Gershwin is also entitled to name the species and has decided to honour museum boss, Patrick Filmer-Sankey.