Predaceous Diving Beetles

A species of Coleoptera capable of swimming in the water using the hairs on its legs, it is also a fearful aquatic predator, both as a larva and as an adult.

A family with a cosmopolitan distribution.

Dytiscus marginalis is a beetle in the Dytiscidae family. It grows up to 4 cm in length and its body is perfectly adapted to life in the water. In fact, it has a hydrodynamic shape, and its last pair of legs has hairs that it uses like oars. Male adults are a shiny black with green upper body. Females instead have a more opaque colouring. Mating usually occurs in autumn and to favour the grip between two individuals, the male has a suction-cup-type swelling on its first pair of legs, while the female has grooves on its elytra (front wings). These beetles are optimal predators, capable of lengthy dives due to the bubble of air they hold under their elytra, which is refilled by sticking the rear part of the abdomen above the surface of the water. They feed on small fish, tadpoles, and other invertebrates.

Beetles in this family have been observed in practically all freshwater environments, from short-lived puddles to large lakes.

Present in bodies of water in the Reserve.