Butterflies and moths in the Lasiocampidae and Pyralidae Families

bumblebee.org insect ebook

Species featured on this page

Latin name Common name Family
Ephestia kuehniella Flour moth Pyralidae
Aphomia sociella Wax moth Pyralidae
Gastropacha quercifolia Lappet moth Lasiocampidae

Gastropacha quercifolia, Lappet moth, adult

Lasiocampidae family - the Eggar moths .

There are about 1000 species found worldwide except in New Zealand, and 12 in Britain. The adults are medium to large sized, brown or brown and yellow, and fat. The adult males have feathery antennae which can detect the scent of a female 100s of metres away. All the larvae are hairy, and these hairs protect them from being eaten by most birds, and can cause irritation in humans. The caterpillar hairs are usually incorporated into the cocoon.

On the left is Gastropacha quercifolia, the lappet moth. It is usually found in scrub, hedgerows, open woodland and sometimes in gardens. It is common in southern England and can be found as far north as Yorkshire.

The eggs are white with grey spots and laid in bands, pairs or small batches on twigs or leaves of the foodplant in July or August and hatch in about 2 weeks.

The caterpillar feeds at night on whitethorn, blackthorn, hawthorn, sallow, apples and other fruit trees after hatching. Then it hibernates on stems near the base of the foodplant. In May it starts to feed again, and when fully grown it can be as long as 80 mm. It has hairs which can cause irritation. It is widespread in Europe. The name comes from fleshy "lappets" that hang down around the prolegs. Pupation is in June, in a tough cocoon of brown/grey silk and hairs spun low on the food plant.

Adults emerge in June or July. The wing length is 28 - 42 mm. The females are larger and darker in colour than the males. They are good fliers and can be seen flying during the day. At rest they are well camouflaged as they look like a bunch of dead leaves.

Both sexes have pectinate antennae, though the female is less pectinate than the male, and they do not have a proboscis. They are generally found among hedgerows and woodland edges. The female emits a sexual attractant pheromone that, to us, smells of charcoal or burnt wood.

Ephestia kuehniella, the flour moth

Pyralidae family

There are 90 British species, and all are small. On the left is Ephestia kuehniella, the flour moth. It is a pest world wide of stored grain and flour products. In many species the males are attracted by the pheromones the female adults emit.

The caterpillar is around 10 mm long when fully grown, and lives in silken tubes among the flour. They overwinter in silk cocoons and pupate in spring.

The adult wingspan is 10 mm. Adults locate each other for mating when the male emits ultrasound. The adults live for only a week or two. Between April and October there can be 3 generations. It is thought to have reached the U.K. in the late 19th century.

Aphomia sociella, the Wax moth

Aphomia sociella is in the Pyralidae family. The female lays her eggs in a bumblebee nest, and once the caterpillars have hatched they proceed to completely destroy the nest. The eat almost everything in their path, and leave a tangle of silk behind them. The bumblebees will carry on at first, but the end result is always a failed nest. For more on this see the bumblebee symbiont page.

Bumblebee nest destroyed by wax moth caterpillars, Aphomia sociella