Australia's spider population has welcomed the addition of three tiny, colourful but totally harmless species, Daily Mail reported.

The newly discovered species of peacock spiders, who call Western Australia home were officially named on Wednesday.

Named by spider taxonomist Joseph Schubert, the new species are now known as Maratus aquilus, Maratus felinus, and Maratus combustus, each identifiable by their distinctive patterns. 

The Monash University research assistant made the discovery with a group of photographers from Project Maratus at Lake Jasper and Mount Romance in Western Australia's south-west.

He says arachnophobes have no reason to fear creepy critters.

'These little guys are completely harmless! They're roughly the length of a grain of rice,' Mr Schubert tweeted this week.

He told 10 daily: 'They're incredibly, small but so charismatic and so colourful.'