These are commonly know as the Whites, Sulphurs and Orange tips. The family has a world wide distribution, and the adults are generally found in open, sunny areas. There are 11 British species in the family. The wingspan ranges from 22 - 70 mm. A typical Pierid flight pattern is a low, looping zig-zag.
The brimstone butterfly on the left, I have drawn the male colouring on the left wing and the paler female colouring on the right. The males are the only bright yellow butterfly in the British Isles. The female is much paler and is sometimes mistaken for a cabbage white butterfly (see below). The brimstone is fairly common in central and southern England.Eggs are laid in May and June.
The caterpillars grow up to 50 mm long, and feed on buckthorn and alder buckthorn.
The chrysalis is attached to a twig of the foodplant at the end of its abdomen, and has a thread around the middle of the body holding it in a sling to the twig.
Adults fly from March to October and hibernate over winter, and have a fast and powerful flight. Wingspan is about 5.6 cm. They have green undersides to their wings, so at rest they resemble a leaf.
The eggs (below) are yellow and laid on the under surface of cabbage and nasturtium leaves in batches of 60 - 100 in May - August and are ridged and ribbed.
The female tests the plant for suitability as an egg-laying site using chemoreceptors on her feet. If she detects mustard oils (present in the brassicas - cabbage family) she will lay her eggs.
Initially the caterpillars (below) stay together to feed, but soon separate to feed alone. They break down the mustard oils in the leaves they eat and sequester them in their body as a chemical defence making themselves taste horrible, so predators avoid them. The yellow/green and black colouration is also a warning to predators that they do not taste nice.
The caterpillar can eat twice its weight per day in leaves. Once it has reached full size the caterpillar stops feeding and starts to climb to find somewhere to pupate. It is at this stage that we can see the caterpillar climbing the walls of houses to pupate under gutters, around windows and in crevices.
Above is a chrysalis with the skin for its final larval moult hanging just below it.
They are probably the commonest butterflies in the U. K. Adult females have more black than males (see above), and have 2 black spots on the forewing. Although the male seems white to our eyes, he has ultra violet patterns that are visible to the female.
Flight speed has been recorded as 2.5 metres per second with a wing beat of 12 per second. Compare this with other insects. They fly from the early spring until autumn.
Above and below is an adult female Orange tip (the males has the orange tip to his forewings, the female does not). They are found throughout Europe on hedgerows woodlands and damp meadows.
In the U. K. the adults fly from April to June. The greenish white eggs are laid singly on the flowerheads of the foodplant, then turn orange and finally dark violet. The caterpillars feed from June to August, and can grow up to 30 mm long, then overwinter as a pupa attached to the foodplant.
Main Lepidoptera page
Above is Phoebis trite, the Straight-lined sulphur, also known as the Buttercup butterfly. It can be found in Central and South America.
Above is the adult Apricot sulphur, Phoebis argante. It has a wingspan of 54 - 67 mm. The hind wings are slightly paler than the brilliant yellow of the fore wings. Females vary from almost white to yellow. It is native to Mexico, Peru, Uruguay and the Caribbean, and is found from sea level up to 1600 m in tropical forests, pastures and road edges.
The Apricot sulphur flies throughout the year in most areas. Adult males sometimes gather in large numbers to drink water that is rich in minerals. Both sexes drink nectar from red flowers.
The eggs are yellow and laid singly on the foodplant.