Coronella austriaca, commonly known as the smooth snake, is a non-venomous species found in Europe. It has a slender, smooth-scaled body, typically grey or brown, with a distinctive dark stripe running along its back. Preferring heathlands and open woodlands, it is a secretive predator, feeding mainly on reptiles and small mammals.

C. perezi, commonly known as Perez's frog, is native to the Iberian Peninsula, which includes Spain and Portugal. It is also found in southern France and has been introduced to the Balearic Islands and parts of North Africa.

Perez's frog typically inhabits freshwater environments such as ponds, streams, marshes, and slow-moving rivers. It prefers areas with abundant aquatic vegetation and can also be found in man-made water bodies like irrigation canals.

This species is well-adapted to a wide range of aquatic habitats, often thriving in both natural and artificial environments. It plays a crucial role in the ecosystem as both predator and prey, feeding on insects and other invertebrates while providing sustenance for birds, mammals, and reptiles.