Zolas also known as River Zora are a variation of Zoras allthough they live in rivers and are very hostile towards Hylians and when in water the shoot fire at people and on land they have been known to use swords and sheilds.
The Zolas do not appear in the old Hyrule from the Nintendo 64 era but seem to be native of the new Hyrule presumably found by Link and Tetra in the NES era. They have their own domain north of Lake Hylia where they mainly swarm allthough they are found in water areas all through Hyrule.
The Zolas are similar to the Zoras in that they have a monarchy, their King Zola is signifcantly larger than all the other Zolas and he lives in a waterfall, selling Zora flippers to anybody even foes of the Zolas for 500 rupees. Though this is only seen once and it is not known if the other Zola tribes have a monarchy like this one.
Legend of Zelda Online
Zolas appear as one of the selectable race in The Legend of Zelda: Online under the Zora category. While in the water they can use their magic to spit fire at foes but while on land they can only attack with swords and sheilds.