Aphrophora alni, the European alder spittle bug, is a species belonging to the family Aphrophoridae.

[3] These 'froghoppers' inhabit dry and moist habitats of lowlands and mountainous areas, forest edges, hedgerows, meadows, gardens and parks, from the lowlands up to mountains at an elevation up to 1,500 metres (4,900 ft) above sea level.

[4] The adults of these large 'froghoppers' reach 9–10 millimetres (0.35–0.39 in) of length,[1] the females are usually slightly larger than the males.

The adults primarily feed on deciduous trees, while larvae prefer herbaceous plants (dicotyledonous).

The larvae live in stems and leaves of herbaceous plants inside the typical foam nest, that protects them against enemies and provide necessary moisture and temperature for their development.