Arkanians.

are there diffrent species of arkanians arca jeth had three fingers while camper and jareal had five fingers.

 

The KoToR comics explain that Jarael and Camper are offshoots of the pure Arkanian species. The offshoots were originally bred with more human eyes and five fingers and a different skin tone, apparently the modifications meant they were better suited as miners. Once the mines "ran dry" the offshoot species weren't useful anymore. They're treated like second (or third) class citizens on their homeworld.

 

Arkanians like Camper and Jarael are "offshoots". That is, they're a genetically modified group of Arkanians designed to be expert miners. Arkanians like Arca Jeth are natural Arkanians with no specific genetic tampering. The variations between Arkanians are explored in more detail in KOTOR #16.

EDIT: Yeah. What she said.