From Dragon Ball Encyclopedia
Girans (ギラン, Giran) are monster-type Earthlings.
The creatures said that they were the Giran Clan and that Giran was their leader in the FUNimation sub.
Excluding Giran, they first appeared when Goku went to find the blockage in the river to Namu's Village. Goku found that the Giras had blocked the river with the race's special ability to create Guru-guru-Gum.
Dragon Ball Z
Giran is a boss character and a playable character in Dragon Ball: Advanced Adventure.