Rose lovers have a special affinity for these dainty little insects since they eat aphids, which are the scourge of rose growers. These small beetles are not hermaphrodites as some people believe due the gender-specific nature of their name. The males are slightly smaller than females but their coloration and behavior is almost identical. They were named for the Virgin Mary, who was often referred to as the Blessed Lady, after the farmers saw the beetles saving their crops from pests. In Germany, their name is Marienkafer, which translates to Mary beetle.
Lady Bug Life Cycle
Scientific & Common Names
Kingdom – Animalia
Phylum – Arthropoda
Class – Insecta
Order – Coleoptera
Suborder – Polyphaga
Superfamily - Cucujoidea
Family – Coccinellidae
Common Names – Ladybug, ladybird, ladybird beetle, lady beetle
The most commonly recognized ladybugs have a bright red, dome shaped shell with black spots. However, there are striped, plain, yellow, and orange varieties as well. There are even pure black ladybugs that prey on mites instead of the normal aphids. Others will prey on eggs, caterpillars, or other insects. There is some evidence of more of an omnivorous diet with some species, but that is less common. A few of the 5000 species, such as the squash beetle and the Mexican bean beetle, are even considered destructive since they feed on valuable crops. They are prey items for birds, rodents, spiders, and wasps. The largest beetles are still less than a half inch long.
A female can lay one thousand eggs in her lifetime. The eggs are laid among the colonies of prey species and the larvae will begin to feed as soon as they hatch. There is evidence that mothers will lay infertile eggs as a food source for the hatchlings when food is scarce. The egg stage lasts for 1-3 weeks, as does the subsequent larvae stage. Larvae of many species more closely resemble a tick than a beetle. The larvae will then form a cocoon and the pupae will later emerge as an adult.
Their bright color is a warning that they can be toxic and they will also excrete, or ‘bleed’, a yellow alkaline toxin when they are alarmed. Ladybugs do not create nests and will often overwinter in houses, causing a slight and harmless infestation in the spring. Ladybugs, despite the gentile nature their name implies, will resort to cannibalism when food is scarce.
These aphid-loving beetles are often used as a natural pest control by both amateur and professional gardeners and farmers. As a result, there are many areas where some species have become invasive and are muscling out native species.
There is some concern for several North American species due to competition from invasive ladybugs, which are becoming much more common. The Coccinella novemnotata, Nine Spotted Lady Beetle, has been almost eliminated from its native range in eastern North America, but there is still hope since there have been sightings. There have also been declines of native species in Great Britain, accompanying a rise in introduced species.
The Lost Ladybug Project, Cornell University
Ladybugs by Keisha Harris
A Field Guide to the Beetles: of North America (Peterson Field Guides) by Richard E. White
Beetles of Eastern North America by Arthur V. Evans
The Southern Living Garden Book: Completely Revised by Editors of Southern Living Magazine