Gergillas were large, bulky creatures with purple-brown skin with a tan underbelly. They had large, oval shaped heads with purple tongues and several sharp teeth. Their eye color varied from black to purple. They had large, bulky arms with two fingers and one thumb on each hand. They had large legs with three toes on each foot. They also had a short, stumpy tail.
Gergillas were friendly creatures, although they were capable of attacking enemies with immense strength. They were intelligent enough to understand directions and maps. They could walk on their legs or on their knuckles. They could also travel at high speeds while running on their knuckles. They could make a very loud roar.
At some point, droids SF-R3 and CAM of the Galactic Society of Creature Enthusiasts crashed their ship onto the planet Vadran where they were helped by a Gergilla.
Another notable Gergilla was Ayuu, the pet/partner of Cyborg treasure hunter Lens Kamo.
By 34 ABY, a drink named after this species, , was served at Seezelslak's Cantina at Black Spire Outpost on Batuu.