Harmless. The adult has no sting and cannot bite, and the caterpillar's horn is not a stinger — it is a soft spike that does nothing at all.
SizeWingspan 60–90 mm
MarkingsBright pink band across the hindwing, usually only visible in flight or when startled · Forewing veins picked out in fine white lines over dark brown
WhereOpen country of almost any kind — deserts, meadows and gardens.
SeasonFebruary to November, in two broods
How to tell it apart
Bright pink band across the hindwing, usually only visible in flight or when startled
Forewing veins picked out in fine white lines over dark brown
One broad pale stripe running the length of the forewing
Heavy, torpedo-shaped body — much more solid than a butterfly's
Hovers at flowers at dusk, and often in daylight too
Where you’ll find it
Most of North America, and well beyond it into Central and South America, the West Indies, and parts of Eurasia and Africa. Very few moths are this widespread.
Open country of almost any kind — deserts, meadows and gardens.
February to November, in two broods.
How it behaves
It feeds on the wing, hanging in front of a flower and drinking through an extended tube, which is why it gets reported as a hummingbird. Unlike the hummingbird clearwing it is mostly a dusk flier, so the usual sighting is a large fast shape working a flowerbed in fading light. It comes to porch lights, and a heavy moth thumping around a bulb at night is often this.
You’ve found one indoors
Nothing. If one is indoors, it will go to the brightest window — turn the inside lights off, open the window, and it leaves on its own. The caterpillars occasionally turn up in numbers on garden plants and in desert years can appear in remarkable abundance; they eat leaves and then leave to pupate in the soil.
Common questions
Is the horn on the caterpillar a stinger?
No. Hornworm caterpillars carry a spike at the rear end and it is completely harmless — no venom, no sharp point that matters. You can pick one up. This is the most common misconception about the group.
Is this the hummingbird moth?
It gets called that, but the moth usually meant is the hummingbird clearwing, which is smaller, has clear windows in its wings and flies in full daylight. If it is large, has solid dark wings with white veins and a flash of pink, and you saw it at dusk, it is this one.
Why is it flying into my porch light?
Most moths navigate by distant light and a nearby bulb overwhelms that. It is not attracted to your house. Turning the light off, or switching to a warmer bulb, stops it happening.
What do the caterpillars eat?
A very wide range of plants, with evening primroses and the rose family especially favoured. Purslane is a common enough foodplant that the larva has been called the purslane caterpillar.
Laura Gaudette · CC-BY