There are over 21,000 species of Noctuidae worldwide, and 415 species in the UK alone making it the largest family of U. K. macro-moths. Many are of economic importance as they include the cutworms and army worms.
In the U. K. most adults are medium sized with fat bodies, and often brown coloured. Worldwide the adults are usually brown or grey, but some have brilliantly coloured underwings which they flash when disturbed. All adults are nocturnal, and are often called the Owlets. Most have powerful flight, and rest with their wings held tent-like over their body - see the Silver Y on the right. Wingspan ranges from 30 - 50 mm.
Adults have a pair of hearing organs (tympana), one of each side of the thorax. The moths themselves do not make any noise, but the tympana allow them to detect the high-pitched sounds made by echo-locating bats, which are a major predator.
The caterpillars tend to be hairless, below is the typical Noctuidae caterpillar body.
Above and below right is the Silver Y moth, Autographa gamma. So-called because of the white y mark clearly seen on its front wings. It is abundant in the UK and Europe, and flies both day and night. Though it is abundant it cannot overwinter in the UK, and is most commonly seen flying in the autumn. It migrates to the U. K. from North Africa and southern Europe. Its wingspan is 32 - 43 mm and forewing length 13 - 21 mm.
Eggs are laid in May and August, however the the eggs laid in August do not survive to breed as adults. The eggs are pale and shiny and vary in colour from green to dark olive.
The caterpillar has only two pairs of prolegs and feeds on almost any kind of plant, but can be a pest species on cabbage and pea plants.
It pupates in a black silk cocoon attached to the foodplant, although the cocoon above is more a silver/blue. It overwinters in southern Europe and as the weather warms migrates as far north as the Arctic Circle. In the UK it has two generations per year.
Above is Cerapteryx graminis, the antler moth. It is a member of the Noctuidae family. This is a male. It is found throughout Europe.
It is commonly found on acid moorland. The wingspan is 30 mm and forewing length of 12 - 17 mm. The adults fly in July and August at night, but also during the day. The female scatters her eggs over grassland.
The eggs overwinter and are pale and shiny. They hatch the following spring.
The caterpillars hatch in spring and as its name suggests the food plants are coarse grasses and rushes, on which it feeds at night from March - June. Then it pupates in the soil.
This beautiful moth (above) is found throughout Europe. Its preferred habitat is grassy areas, woodland rides, verges and embankments. The caterpillar is up to 40 mm long, and thin like a looper with just 3 pairs of prolegs. It feeds on clover, black medick, lucerne, bird's-foot trefoil and grasses mainly at night, and rests along a grass stem during the day. There is one generation a year. The eggs are laid in June and hatch after 3 weeks. In September it pupates in a cocoon among grasses or just below ground and overwinters. The adult emerges the following year in May or June and flies during the day when it is sunny until early July.
Above is a preserved specimen of Xestia xanthographa, Noctuidea, the square-spot rustic. It is found in open habitats on grasses and low vegetation. Its wingspan is 32 - 35 mm, and the adult is seen flying in August and September. The wings vary from whitish-brown through red and greyish-brown to almost black. The caterpillars are nocturnal and feed in winter, mainly on grasses. They prepare a pupal cell underground in May, but do not actually pupate until July.