Scientists from the Queensland Museum have discovered two new species of goblin spiders on the state's Darling Downs.

Dr Barbara Baehr says her team discovered the Opopaea broadwater, also known as the jellybean goblin spider in Dalby.

They also discovered the Leichhardteus badius, or reddish brown swift spider, while exploring a rainforest in the Bunya Mountains last year.

The museum says the genus name Leichhardteus was chosen to honour German explorer and scientist Ludwig Leichhardt, who came to Australia in 1842 to study wildlife.

It says the species name badius refers to the Latin badium, meaning reddish brown in reference to the body colour.

It was also chosen to honour former Greens senator Bob Brown, who rescued rainforest environments.

Dr Baehr says the jellybean goblin spider is only one millimetre long and has an armour-like shell.

"That helps them to protect themselves from desiccation because they're very small, so they're very sensitive about humidity, so they have developed this little shell," she said.

Dr Baehr says they are important discoveries.

"It's important to know about the species who are around us because if you don't know them, we can't protect them, and they will extinguish before we even know them," she said.