[1] Based on seven specimens, adult Occidozyga tompotika measure between 28.3 and 36.5 mm (1.11 and 1.44 in) in snout–vent length.

Males are slightly smaller than females and have some secondary sexual characters including enlarged thenar tubercle at the dorsal surface of first finger and paired vocal sac, but are similar to females in body proportions.

Lower parts and gular surfaces are heavily marbled with dark brown.

[1] This species has been collected between 462 and 778 m (1,516 and 2,552 ft) above sea level in very shallow creeks with continuous flow.

Its more webbed toes suggest that it is more aquatic than the related Occidozyga semipalmata.