Knopper Oak Gall Wasp

The Knopper Oak Gall Wasp lays its eggs in oak acorns, causing an obvious deformity, which is probably chemically induced.

Species introduction

At a glance
Latin name: 
Andricus quercuscalicis
Family: 
Gall Wasps
Family Latin name: 
CYNIPIDAE
Category: 
Insects other

Species description

Species description

Andricus quercuscalicis wasps were not seen in Britain before the 1960s, yet are now seen frequently throughout the country. The Knopper Oak Gall Wasp lays its eggs in oak acorns using its egg-depositing ovipositor. As the egg develops into larvae, the acorn develops an obvious deformity, which is probably chemically induced. These Knopper Oak Galls are specific to Pedunculate Oak trees, a type that exists in the Cemetery. This deformation renders the acorn infertile. 

This species - along with mites - are exceptions to the species listed on this website in that we have not seen the species, but we know that the galls that they have created are proof of their earlier presence.

Species photographs

Larger photograph(s) (click to magnify)

Details

Species family information

Gall wasps are wasps that induce galls on plants, which aid the development of their larvae. They are generally small insects. Galls develop in the tissue of plants after the female insect lays eggs. After the eggs hatch into larvae, the galls provide nourishment for them and protection of them.

Category information

Insects evolved in the Ordovician from a crustacean ancestral lineage as terrestrial invertebrates with six legs (the Hexapoda). This was the time when terrestrial plants first appeared. In the Devonian some insects developed wings and flight, the first animals to do so. An early flying group was the Odonata from the Carboniferous, the damselflies and dragonflies, which have densely-veined wings and long, ten-segmented bodies. They are day-flying carnivores, with an aquatic larval stage, so are commonly seen flying near water. The carnivorous larvae are called nymphs. Odonata species are short-lived, damselflies surviving for 2-4 weeks, dragonflies for up to 2 months.

Some insect groups in the Cretaceous co-evolved with the flowering plants, and they have had a close association ever since. These groups are the Hymenoptera (bees, wasps, and ants), the Lepidoptera (butterflies and moths), the Diptera (flies), and the Coleoptera (beetles). The diversity of beetles is astonishing. Of all the known animal species on the planet, one in five is a beetle!