Bosca's newt is relatively small, growing to around 9 cm. total length. Both sexes are lightish brown in colour on the upper parts, with small dark spots. The belly is orange or red, with a light band between the belly and flanks. Both the belly and throat may be spotted. The male is very similar to the female, although the female's cloacal swelling is slightly pointed. The male also has slight dorsolateral ridges, and a small crest on the tail. No crest is present on the male's body.

Similar to Palmate Newt but males lack tail filament. Inhabits mainly small ponds but sometimes lakes within caves.