Hawk-moth caterpillar identification: eight UK species

Hawk-moth caterpillars have one thing in common: they're pretty impressive. Usually large, distinctively marked and with a characteristic 'horn' at the tail end, they're a good group to get to grips with when learning who's who. Which of these commonly encountered species have you spotted?

How to identify

A thick, brown caterpillar with a small, stubby horn at the tail. The elephant hawk-moth gets its name from the trunk-like head which retracts and extends from its bulbous neck. When threatened it swells its neck, making its four large eye spots more prominent. Some forms can be bright green.

Size

Up to 80mm in length when fully grown.

When to see it

July - September. Often spotted in late summer undulating across paths in search of somewhere to pupate.

Where to find it

Common and widespread across much of the UK, although less frequent in Scotland and the north of England. Its range is however expanding. Found in almost all habitats, including woodlands, hedgerows and gardens. 

Caterpillar foodplants

Willowherbs, fuchsias, Himalayan balsam, bedstraws and enchanter's nightshade.

How to identify

Similar at first glance to its larger cousin (above) but lacking the tail horn of other hawk-moths. The eye spots have reddish centres and the second set are much smaller than the first. 

Size

Up to 60mm in length when fully grown.

When to see it

July - September.

Where to find it

Most common across England and Wales, becoming more scarce north of the Humber and in Northern Ireland. Found mainly in grassy habitats, heathland and sometimes gardens.

Caterpillar foodplants

Mainly bedstraws but sometimes also rosebay willowherb.

How to identify

The poplar hawk-moth has a light green or yellowish-green caterpillar covered in dense yellow speckles. Look for pale yellow stripes that cut diagonally across the body and a yellow tail horn. Some forms also have pinkish-red splotches along the body. 

Size

Up to 70mm in length when fully grown.

When to see it

July - September.

Where to find it

Thought to be our commonest hawk-moth. Widespread across the UK in most habitats including woodlands, parks and gardens.

Caterpillar foodplants

Poplars, aspen, willows and sallows.

How to identify

This hefty chap is pretty unmistakable. The privet hawk-moth caterpillar has a bright green body with distinctive white and purple diagonal stripes. The large tail horn is curved and black-tipped. Also look for the dark ring around the head. 

Size

Up to 85mm in length when fully grown.

When to see it

June - August.

Where to find it

Common across the south of England, parts of Wales and East Anglia, becoming scarce further north. Absent from Northern Ireland and Scotland. Found in a number of habitats including woodland, hedgerows, parks and gardens.

Caterpillar foodplants

Mainly feeds on privet but also ash, lilac, honeysuckle, holly, guelder rose and some garden plants.

How to identify

Appears similar to the poplar hawk-moth at first glance but can be told apart by the tail horn, which is blue on top and often red and yellow underneath. Once mature and ready to pupate the body turns a darker, greyish-pink colour. 

Size

Up to 65mm in length when fully grown.

When to see it

July - September. Often encountered on the ground in later summer when searching for somewhere to pupate.

Where to find it

Common across most of England and Wales south of the Humber but absent from Scotland and Northern Ireland. Found in woodland, parks and gardens as well as on street trees in urban areas.

Caterpillar foodplants

Limes (as the name suggests) but also a range of other deciduous trees including birch, elm, alder and London plane.

How to identify

A green caterpillar with a blue-ish tail horn when mature. Can be told apart from the lime hawk-moth caterpillar (above) by its white diagonal stripes along the body. Look also for the bright yellow collar bordering the flat, triangular head.

Size

Up to 75mm in length when fully grown.

When to see it

June - September.

Where to find it

Common and widespread across England and Wales, becoming more scarce in Northern Ireland. Mostly absent from Scotland. Found in woodland, orchards, parks, gardens and riverside habitats where willows are found.

Caterpillar foodplants

Mainly willows, sallows and apples but also aspen and poplar.

How to identify

When mature the pine hawk-moth caterpillar has a dark green body with a brown stripe along the back and broken creamy lines along its sides. The head is also brown and the tail horn black.

Size

Up to 80mm in length when fully grown.

When to see it

July - September.

Where to find it

Most common in south east England and East Anglia, becoming more scarce in central England. Mostly absent from Wales, Scotland and Northern Ireland. Found in coniferous woodland, heathland and sometimes gardens.

Caterpillar foodplants

Mostly feeds on the more mature needles of Scots pine, but occasionally other pines and spruces.

How to identify

Mostly green with with a thick, creamy yellow stripe along the side and a white line above. The tail horn is black and yellow tipped when mature.

Size

Up to 55mm in length when fully grown.

When to see it

Mainly encountered in July and August.

Where to find it

Adult hummingbird hawk-moths are summer migrants to the UK and can be encountered almost anywhere. Look for their caterpillars where their favourite foodplants are found.

Caterpillar foodplants

Bedstraws and wild madder.