About Andricus dentimitratus (Rejtö, 1887)
Andricus dentimitratus is a gall-forming wasp that belongs to the genus Andricus. Adult wasps lay their eggs on multiple oak species. Developing larvae then trigger the oak trees to produce a large, ornate gall. The oak species parasitized by this wasp are Quercus frainetto, Q. petraea, Q. pyrenaica, Q. pubescens and Q. robur. This gall forms from the cup of an oak acorn. In cross-section, the gall has a shape similar to a mushroom. It is woody in texture, maroon in color, shiny and sticky. The gall can grow up to 25 mm high and 20 mm wide. The portion of the gall that resembles a mushroom cap shows varied lobed or toothed structures. The adult wasp emerges from the narrow gap between the mushroom-like cap section and the base of the gall. This species occurs around the Mediterranean region, in areas where its suitable host oak species live. It has been recorded in countries including Spain, southern France, Hungary, Italy, Slovakia and Turkey.