This family contains the swift-flying hawkmoths, they are known as hawkmoths as their flight is fast and manoeuvrable, and they are relatively large. There are around 1050 species worldwide; most are tropical, but there are 18 species in the U. K., although only 9 are resident; the other 8 are immigrants.
The eggs are usually attached to the foodplant either singly or in pairs.
Below is the typical caterpillar body shape. Many of the caterpillars have eyespots and a horn at the rear end.
Below is a typical Sphingid pupa. Pupation is usually in the soil or leaf litter beneath the foodplant.
The adults are usually fairly large with rather stout bodies. Adult females are usually larger than males. Adult males rest with the tip of their abdomen curled upwards. The forewings are narrow and pointed, see below. Many are nocturnal, but the bee and hummingbird hawkmoths are day fliers.
The front wings can be twice as long as the rear wings. And the rapid wing beating, and habit of many in the family of hovering whilst feeding makes some of these moths resemble hummingbirds.
A few species have clear patches in their wings, and are sometimes mistaken for bumblebees. Worldwide the wingspan ranges from 32 - 155 mm.
In the 19th century botanists were mystified by the Madagascan orchid, Angraecum sesquipedale, as they couldn't see how it could be pollinated. They knew something was pollinating it, but what? You see the nectar was to be found only in the last 1 cm at the end of a narrow spur 20 - 30 cm long.
Darwin was shown the flower. It is large and white, and the nectar is thick and fragrant. So this told him that in the thick jungle, the scent and the whiteness of the flower were probably the things that attracted the pollinator. Now white fragrant flowers the world over are often pollinated at night by moths. So Darwin predicted that a moth with a tongue (proboscis) of 30 cm or more was the elusive pollinator. At that time no such moth had been found, nor was one found in Darwin's life time. But 40 years after he had made his prediction such a moth was found, Xanthopan morgani subspecies praedicta.
The Convolvulus hawk moth, above, is found in most of Europe, Africa, Asia and Australia. It does not breed in the U. K., but migrates from North Africa, and has been seen as far north as Orkney. The adult wingspan is 80 - 120 mm. making it the largest moth found in the U. K. It is usually seen hovering over flowers around sunset using its very long proboscis (around 10 m long) to feed on the wing. Its proboscis is long enough to reach the nectaries of Nicotiana sylvestris, one of its favourite flowers. In the U. K. adults are seen from June to December, but are most common in late summer. Adults can live for about five weeks.
The adult male has darker markings than the female, and during the day they rest on tree trunks and stones where their markings help to camouflage them. If you try to pick one up you may get a surprise as they have sharp spines on their legs making them painful to handle. The adult eyes are very large with around 27,000 facets, giving them excellent low-light vision. They locate their flowers by both sight and smell.
The caterpillar feeds on bindweed and can grow up to 100 mm long.
Above is Cocytius lucifer, a hawk moth found in Mexico and South America. From this preserved specimen you see that it has an extremely long proboscis. The adult wingspan is 14 - 16 cm, and it flies throughout the year. The females attract the males by releasing a pheromone from a gland at the tip of the abdomen. The caterpillars are green and white and hairless. They grow up to 11.8 cm long.
Above is Hemaris officinalis, the snowberry clearwing. Found all over the US. Adults are often mistaken for bumblebees. As you can see in the photograph the wings have large clear patches which is where the common name comes from. Even when feeding the wings beat fast, so that they are almost a blur. They feed on lantana, honeysuckle, snowberry, lilac and thistles. The adults are day fliers, and the wingspan is 3.2 - 5.0 cm. The caterpillars feed on snowberry, honeysuckle and dogbane. They pupate in cocoons in leaf litter.
Above is the Death's head hawkmoth, Acherontia atropos adult and pupa, is the largest British hawkmoth, with a wing span of up to 15 cm, front wing length 5.2 - 6.0 cm. A skull pattern in the hairs of the thorax and a yellow banded abdomen. The adults are usually immigrants from the continent and arrive in the autumn, but are unable to overwinter. The adults can make a mouse-like squeaking sound by expelling air through their proboscis past a structure that vibrates like a saxophone reed. Adults usually fly from August to October, but they can be seen earlier. Lepidopterists can also buy eggs to rear in captivity. Eggs are laid on potato plants, but in captivity they can be reared on privet. Usually they are restricted to the south east of England.
With its wings spread it is easy to see where the Eyed hawkmoth, above, gets its common name. The eye markings are hidden when the moth is at rest, but flashed when it is disturbed. When it is disturbed and exposing its eye spots it rocks to and fro, and this has been observed to frighten off birds as the moth has some resemblance to a cat's head. It can be found in Europe and temperate Asia, but is absent from Scotland, in woodland, hedgerows, riversides, parks and orchards.
Caterpillar foodplants include sallows, willow, aspen, poplar, birch, hazel and apple. Caterpillar length when fully grown is up to 80 mm, and it has the typical Sphingid horn at the rear (see the drawing above), which is grey/blue. It is bluish-green to yellow-green with tiny white spots and pale stripes, and a green head with two yellow stripes. The spiracles (breathing holes) are very easy to see as they are white with a red rim.
The Eyed hawkmoth has one generation a year. Eggs are laid singly or in pairs on the underside of the foodplant leaf in May or June, and hatch in 2 - 3 weeks. Caterpillars feed from June to September, and pupate in cocoon just below the soil surface, near the base of the foodplant. The pupa is a shiny brown/black. Adults emerge in Early May or June. Adults do not feed. Fore wing length is 36 - 44 mm.