New Delhi: Scientists have discovered two new species of jumping spiders from the Valley of Flowers National Park in Chamoli district of Uttarakhand, increasing India's catalogued diversity of this family of arthropods to 250.

The two tiny creatures - just 2mm to 5mm in size - appear to be geographically confined to the alpine meadows of the valley at altitudes between 3,200 and 3,600 metres above sea level, the researchers at the Zoological Survey of India (ZSI), Calcutta, said.

The ZSI team has just described their findings in the journal ZooKeys. Jumping spiders represent the most diverse among spider families with over 6,000 species described from around the world but zoologists believe India's diversity of jumping spider remains underrepresented.

Australia, Brazil and China each have documented over 450 jumping spiders. "Given India's megadiversity of habitats, it is believed many jumping spiders are yet to be discovered," John Caleb, a research associate at the ZSI and lead author of the paper said.

Jumping spiders are known by that terminology because of the capacity to leap across long distance. But unlike insects such as grasshoppers that use muscular force, Caleb said, jumping spiders use fluids in their legs and hydraulic mechanism to make their leaps.

One species, named Nandicius vallisflorum, was described through a single female specimen, while the other species, Pellenes himalaya, was described on the basis of four male and three female specimens. Both were collected in 2017 and analysed by ZSI scientist Vikas Kumar, S.K. Sajan and Caleb.

The scientists found the spiders during field surveys in 2017 conducted as part of efforts to document faunal biodiversity in the Himalayas under a research project supported by the Union environment and forests ministry led by ZSI director Kailash Chandra.