Harmless. A native ladybug does not bite, sting or damage anything, and a garden with them in it has fewer aphids. If something ladybug-shaped bit you, it was almost certainly an Asian lady beetle.
Size5–8 mm
MarkingsDomed, almost hemispherical, with a hard glossy shell · Seven black spots on red in the classic species — three each side and one across the join
WhereAnywhere aphids are — garden plants, hedgerows, nettles, crops and allotments.
SeasonActive spring to autumn; overwinters in sheltered spots as an adult
How to tell it apart
Domed, almost hemispherical, with a hard glossy shell
Seven black spots on red in the classic species — three each side and one across the join
Plain black-and-white plate behind the head, with no M or W marking
Short clubbed antennae, usually tucked out of sight
Larva looks nothing like it: elongated, spiky, black with orange marks
Where you’ll find it
The seven-spot is established across the United States. Several hundred other ladybug species live here too, in almost every colour combination including entirely black, pink and yellow.
Anywhere aphids are — garden plants, hedgerows, nettles, crops and allotments.
Active spring to autumn; overwinters in sheltered spots as an adult.
How it behaves
Both the adult and the larva eat aphids in serious quantity, which is the whole reason ladybugs have the reputation they do. The bright colouring is a warning rather than decoration: when threatened it releases a bitter yellow fluid from its leg joints, and most birds learn quickly. Adults overwinter tucked into bark, leaf litter and window frames, sometimes in small groups.
You’ve found one indoors
Nothing at all — leave it be. If one is indoors in winter it is overwintering rather than lost, and it will do no harm; put it somewhere cool and sheltered rather than out into the frost. Ladybugs are one of the few insects genuinely worth encouraging in a garden.
Common questions
Do the spots tell you its age?
No, and this is the most persistent ladybug myth. The number of spots is fixed by species. A seven-spot has seven for its whole adult life.
Do ladybugs bite?
Native ladybugs essentially do not. The Asian lady beetle does, and it is the usual answer when somebody is sure a ladybug bit them. Check the plate behind the head for a white M.
What are the spiky black things on my plants?
Almost certainly ladybug larvae, which look nothing like the adults and get killed as pests constantly. They eat more aphids than the adults do.
Are yellow or black ladybugs a different insect?
Usually not. Ladybug colouring varies enormously across the several hundred North American species — yellow, orange, pink, cream and entirely black are all normal.
Dr. Guido Bohne · CC-BY-SA