The European chafer (''Amphimallon majale'' classified as ''Rhizotrogus majalis'' prior to Montreuil 2000) is a beetle of the family

Scarabaeidae The family Scarabaeidae, as currently defined, consists of over 30,000 species of beetles worldwide; they are often called scarabs or scarab beetles. The classification of this family has undergone significant change in recent years. Several sub ...

. Formerly found only in continental Europe, this

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

is now found at

temperate In geography, the temperate climates of Earth occur in the middle latitudes (23.5° to 66.5° N/S of Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ranges throughout t ...

latitudes in North America. The large, white grubs of ''A. majale'' feed on the roots of most cool-latitude

grass Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns an ...

es, both wild and cultivated. This has made the European chafer an enemy of

lawn A lawn is an area of soil-covered land planted with grasses and other durable plants such as clover which are maintained at a short height with a lawnmower (or sometimes grazing animals) and used for aesthetic and recreational purposes. L ...

Description

Imago

Adult beetles are medium-sized, light reddish-brown, and approximately long. Their

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum (dorsal), the prosternum (ventral), and the propleuron (lateral) on ea ...

features a narrow band of light-yellow setae and the underside of the

thorax The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the cre ...

has similar coloured setae. The tip of the

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...

protrudes beyond the wing covers. Wing covers have longitudinal grooves. left, alt= a picture of a European Chafer larva on dirt, The larva of the European chafer

Larvae

Larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The ...

e are white-coloured and C-shaped, with a yellow-brown head and six jointed legs. The raster has two distinct rows of small spines that diverge outward at the tip of the abdomen. Fully grown larvae are long.

Pupae and eggs

The

pupa A pupa ( la, pupa, "doll"; plural: ''pupae'') is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their ...

e of the European chafer resemble those of the other turf-infesting scarab beetles, such as the

Japanese beetle The Japanese beetle (''Popillia japonica'') is a species of scarab beetle. The adult measures in length and in width, has iridescent copper-colored elytra and a green thorax and head. It is not very destructive in Japan (where it is controlle ...

. Pupae are about long. Eggs are shiny and oval, milky-white when freshly laid, but later turning dull gray, approximately .

Life cycle

Life cycle of ''A. majale'' The European chafer has a 1-year life cycle. The imago, or adult beetle, stage is quite short, lasting 1–2 weeks. The adults come out of the ground in late spring and mate in large swarms, usually on low trees and shrubs. The beetles are most active on warm, clear nights when the temperature is above . They emerge at about 8:30 pm, mate through the night, and return to the soil by daybreak. Beetles may return to the trees to re-mate several times over the mating period. Late in the period, the adult carcasses may litter the ground beneath trees used for swarming. Female chafers lay 20-40 eggs over their lifespan. They are laid singly, deep in moist soil, and take 2 weeks to hatch. The grubs hatch by late July. The grub population consists mainly of first

instar An instar (, from the Latin '' īnstar'', "form", "likeness") is a developmental stage of arthropods, such as insects, between each moult (''ecdysis''), until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or ass ...

s in early- to mid-August, second instars by early September, and third instars by mid-September to early October. In frost zones, the grubs feed until November, then move deeper into the soil. In frost-free areas, the larva will feed all winter. Vigorous feeding occurs from March through May. In early June, the grubs again move deeper, from , to form earthen cells and pupate. The pre-pupal and pupal stages last 2–4 days and 2 weeks, respectively. By June, the new beetles begin emerging.

Lawn destruction

The damage caused by chafer infestation to residential lawns is exacerbated by the fact that its grubs are an attractive food source for local fauna such as crows, skunks and raccoons, who relentlessly dig up the turf in search of the morsels. Homeowners often find themselves bewildered by the speed and extent of the destruction which may ensue.

References

*Montreuil, O. 2000. Cladistic systematics of the genus ''Amphimallon'' (Coleoptera: Scarabaeidae: Melolonthinae). European Journal of Entomology 97: 253–270. *Potter, Daniel A. ''Destructive Turfgrass Insects: Biology, Diagnosis, And Control'', Ann Arbor Press, Michigan, 1998 {{Taxonbar, from=Q5413482 Amphimallon Beetles of Europe Beetles described in 1789 Invasive agricultural pests