Ilybius fenestratus is a species of beetle found in many countries in Europe. It was first described by Johan Christian Fabricius in 1781. The scent gland of this species of beetle is natural source for the anabolic steroid boldenone (Δ-testosterone).

Ilybius quadriguttatus is a species of beetle native to Europe and Near East. In Europe, it is found in Austria, Belarus, Belgium, Bulgaria, Croatia, the Czech Republic, mainland Denmark, Estonia, Finland, mainland France, Germany, Great Britain including the Isle of Man, Hungary, mainland Italy, Kaliningrad, Latvia, Liechtenstein, Lithuania, mainland Norway, Poland, Romania, Russia, Slovakia, Slovenia, mainland Spain, Sweden, Switzerland, the Netherlands, Ukraine and Yugoslavia.

The sooty mud dweller is a masterful aquatic predator, with a sleek, streamlined body adapted for a life submerged in freshwater habitats. As a larva, it exhibits a voracious appetite, feeding on other aquatic invertebrates, while adults often hunt smaller prey such as tadpoles. This species has developed a specialized method of respiration, carrying a bubble of air beneath its wing cases, which allows it to extract oxygen while submerged, embodying an elegant synthesis of form and function.

Hygrotus versicolor is a species of Dytiscidae native to Europe.

Hygrotus inaequalis is a species of Dytiscidae native to Europe.

Hygrotus impressopunctatus is a species of Dytiscidae native to Europe.

Nebrioporus elegans is a species of beetles in the family Dytiscidae. It is found in Europe.