Ladybirds guide: why do they have spots, do they bite, ladybird life cycle and how many species are there?

Ladybirds (known as ladybugs in some countries) or Coccinellidae are one of the 103 families of beetles in Britain – an order of insects that comprise 4072 species at the last count!

Published: September 22, 2022 at 3:45 pm

Ladybirds are very familiar species to most of us, even from our childhoods as regular characters in books, TV shows and films. The bright colouration of some species means we easily spot them, particularly when they come out to bask in the sunshine after hibernation.

How many species of ladybirds are there?

It's likely you've seen or heard of some of our UK ladybirds such as the 7-spot and 2-spot, but did you know that there are 47 species of ladybird currently resident in Britain? There have been a few new arrivals over the last few decades including the large and brightly coloured bryony and harlequin ladybird but also a few of the tiny and so-called inconspicuous ladybirds.

There are thousands of ladybird species worldwide with recent studies suggesting there are more than 6000!

Professor Helen Roy is an ecologist at the Centre for Ecology and Hydrology, and runs the UK Ladybird Survey. She provides her expertise on these fascinating insects:

Why do ladybirds have spots?

Ladybirds are indeed varied, ranging in appearance from dull brown to bright yellow and black. Though some ladybirds have patterns verging on checks and streaks, a spot is the simplest pattern for them to develop. Spots occur throughout all animal groups, from freckles to a full dapple. All it requires are central points creating the pigment, and these are usually fixed at the embryo stage under genetic control.

From an evolutionary perspective, all aposematic ladybirds (those whose markings warn predators of a foul taste) should look the same, thereby giving a consistent message. Yet great variation exists, not only between species but between individuals of the same species.

Take the two-spot. Typically red with two black spots, it can also be black with four or six red spots. Studies have shown that it is more palatable than other species and thus mimics its more toxic relatives as a form of defence.

The seven-spot ladybird can devour more than 5,000 aphids in its lifetime.

Are ladybird spots symmetrical?

Ladybirds do tend to be almost symmetrical but just sometimes we see individuals that have slightly different coloured wing cases or in some very rare cases very different contrasting wing cases. This is mostly caused by genetic mutations but sometimes physical damage can also change the appearance of a wing case with blemishes appearing following cold damage or from the peck of a bird.

What is the ladybird life cycle?

A four-spot ladybird laying eggs. © Gilles San Martin via Flickr

Ladybirds, like butterflies, undergo complete metamorphosis. That is their life cycle comprises a pupal stage, in which the grub-like larva transforms into the adult beetle.

In Britain, adult ladybirds spend the winter months in a dormant state. In spring as the weather gets warmer and the days longer the ladybirds begin to stir. At first they feed on a variety of high-energy foods including pollen and nectar but also they begin to seek out their favourite foods too. In some cases that’s aphids or scale insects and for other ladybirds its plants or mildew. They then begin to pair up and mate.

Ladybird eggs, bright yellow ovoid structures, are often seen from March and throughout the summer months. These hatch after a few days to a week into tiny little larvae.

These larvae will go through four stages, increasing dramatically in size, before pupating. The new generation adults appear from April or May onwards depending on the weather. The time taken for a ladybird to complete its life cycle is dependent on the temperature. The warmer it is the faster the development of the ladybirds.

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Do ladybirds bite?

Carnivorous ladybird mandibles. © Gilles San Martin via Flickr

Like all beetles, ladybirds have biting mouthparts and so they can bite. However, mostly ladybirds are occupied with finding a mate or food or a place to lay eggs or a place to spend winter and so even when they land on a person they only bite very rarely.

In hot summers when ladybirds are extremely abundant and their food is scarce the incidence of biting increases. Some people have observed ladybirds taking moisture from their skin in very hot weather. Ladybird bites are not painful – they have very tiny mouthparts!

What do ladybirds eat?

Different species of ladybird have different food preferences. Many are predators feeding on pest insects such as aphids or scale insects but others feed on plants and some on mildew on the surface of leaves. The larvae and adults tend to feed on the same food types.

What eats ladybirds?

The wing cases of many species of ladybird exhibit bright warning colours – signalling to predators that they taste horrible. Some birds that feed in flight, such as swallows, swifts and house martins, sometimes consume ladybirds. Some other birds have also been observed feeding on ladybirds or with the remains of ladybirds in their nests.

However, predation of ladybirds by birds is thought to be quite rare. Ladybirds are sometimes caught up in spiders webs and spiders have been seen feeding on them.

Ladybirds exude a sticky yellow substance called reflex blood when attacked and this can make feeding on them tricky. Indeed predators have been seen frantically trying to clean the substance from their beaks or mouthparts after grappling with a ladybird.

Do ladybirds have parasites?

Laboulbeniales on a harlequin ladybird. ©Gilles San Martin via Flickr

The braconid wasp, Dinocampus coccinellae, is one of the best known. Only females are known for this species of wasp and each one has the potential to lay about 200 eggs. The wasp usually lays an egg into the adult ladybird. The egg hatches inside the ladybird and the emerging larva feeds on the inside of the ladybird although it also amazingly produces feeding cells of its own called teratocytes.

The legs of the host ladybird are left functioning throughout the development of the wasp. The wasp larva emerges from the body of its host and pupates between the legs of the ladybird sticking the ladybird to whatever surface it happens to be on.

With the leg muscles still intact, the ladybird can twitch frantically over the wasp cocoon essentially acting as a bodyguard. There are various other parasites that also attack ladybirds including some flies but known are as easy to see as D. coccinellae.

Ladybirds are also susceptible to fungal pathogens and can very occasionally be seen with a white fungus emerging through the body segments. This is Beauveria bassiana. Another fungus is more commonly seen - Hespermoyces virescens.

This fungus forms tiny fruiting bodies on the surface of ladybirds – often on the top of females and the underside of males because it is transmitted during close contact particularly during mating. These different fungi are intriguing but even their names are the subject of some debate – we have much to learn about ladybird pathogens.

Perhaps surprisingly there is no evidence that predators, parasites or pathogens have any overall effect on the population size of ladybirds.

Are ladybirds poisonous?

Ladybirds contain a cocktail of chemicals in their haemolymph (insect blood) and these taste really unpleasant but they are not very toxic. A bird would have to eat many, many ladybirds to feel any adverse effects but the sticky reflex blood that the ladybird exudes would deter the predator well before it reached dangerous levels of ladybird toxins!

How to submit records of ladybirds

The ladybird records that people have been submitting over the decades have increased our understanding of the status and trends of ladybirds. Indeed, without these records we would have a very poor understanding of the state of Britain’s ladybirds. We encourage sightings of all ladybirds and there are various ways in which you can send your records:

How high can ladybirds fly?

Ladybird taking off. © Gilles San Martin via Flickr

Ladybirds can fly very high. Using radar technologies the flight paths of ladybirds were tracked to see how high and how fast they were flying. Some ladybirds flew above 1 100 m over the ground at speeds of more than 60 km h-1.

Of course the wind and thermals from the ground would have assisted the ladybirds on their journeys but it is still remarkable to consider the dispersal potential of these small insects.

We also know that ladybirds hitch lifts on planes, cars, trains and boats with high numbers seen on cruise ships and others observed in train carriages.

Where do ladybirds go during winter?

It is a tricky time for ladybirds in winter– not only are the cold temperatures far from ideal but food is scarce. So they take the fading light and falling temperatures as a trigger to find a sheltered place to become dormant.

Some species opt for burying themselves under leaf litter and others disappear into bark crevices. A few species favour buildings as their preferred winter hideout; harlequin ladybirds form large groups in the corners of window frames from autumn onwards.

Will different species overwinter together?

In most cases, groups of ladybirds are dominated by one species, but it is not uncommon to see a few interlopers. Two-spot ladybirds are sometimes seen nestled within aggregations of the much larger harlequin ladybird.

In the spring and summer, harlequin ladybird larvae will feed on immature two-spot ladybirds, but all ladybirds spend winter in the adult stage so are not vulnerable to attack (well, at least not from other ladybirds, but they do have to contend with fungal diseases and other parasites).

When do ladybirds emerge from their huddles over winter?

Harlequin ladybird winter aggregate. © Gilles San Martin via Flickr

Ladybirds often huddle together over winter sometimes in very high numbers and sometimes in small groups. As soon as the day length increases in late winter and early spring the ladybirds begin to stir but they often return to the group at the end of the day until the temperatures increase.

Once spring is underway then the ladybirds leave their winter groups to find food and a mate so their life cycle can begin again.

How to identify common ladybirds in the UK

Ladybirds can be distinguished from other beetle families by taking a close look at a few characteristics. Ladybirds have more or less clubbed antennae that usually have 11 segments. The antennae are quite short particularly in contrast to leaf beetles that can look very similar to ladybirds but have long antennae. Ladybirds also have short legs extruding from their oval or round bodies.

If you take a very close look you would notice that the ends of the legs (the tarsi) bear two claws and usually have four segments but the third segment is very small so often they seem to only have three segmented tarsi.

Ladybirds are often brightly coloured and strikingly patterned beetles but this is not always the case. Some ladybirds are tiny, brown and slightly hairy. The colour patterns of many of the so-called conspicuous ladybirds can be highly variable and spot number can be an unreliable characteristic for identification when used alone.

However, by looking at leg colour or the markings on the plate behind the head (the pronotum) it is possible to identify most insects with relative ease.

7-spot ladybird (Coccinella septempunctata)

A 7-spot ladybird (Coccinella septempunctata) just after emergence from the pupae. The orange colour (not red) is typical of these new generation individuals. ©Gilles San Martin via Flickr

The iconic ladybird – with bright red wing cases and three black spots on either side plus one just behind the pronotum (the plate behind the head). It is quite a large (6mm) aphid-feeding ladybird and very common throughout much of Britain.

It favours the aphids on low-lying vegetation such as herbaceous plants including nettles and many crop plants.

Fact: In the summer of 1976 huge numbers of 7-spot ladybirds were seen across the UK with some people observing such high numbers on beaches that the tideline appeared red.

2-spot ladybird (Adalia bipunctata)

The 2-spot ladybird (Adalia bipunctata). ©Gilles San Martin via Flickr

The typical form of this ladybird is red with one black spot on either wing case but there are many other colour forms including black wing cases with four or six red spots. The front spots of the black colour form extend to the edge of the wing cases and this can be a useful characteristic to distinguish this species from others such as the pine ladybird.

2-spot ladybirds are often found feeding on aphids in deciduous trees such as lime and sycamore but are also common on garden shrubs including roses and many crop plants. In recent years, there have been dramatic declines in this previously common and widespread ladybird.

Fact: 2-spot ladybirds are one of the few species in the UK to have more than one generation a year. This species can breed continuously whereas many others require the cold winter moths to become reproductively mature.

10-spot ladybird (Adalia decempunctata)

10-spot ladybird (Adalia decempunctata). ©Gilles San Martin via Flickr

The typical form of this ladybird, a close relative of the 2-spot ladybird, is orange with 10 black spots which appear in the configuration of 1:3:1 on either wing case.

Note that harlequin ladybirds can look very similar but are much larger than 10-spot ladybirds and often have two spots towards the front of the wing cases whereas the 10-spot ladybird has just one. There are a few other striking colour forms of the 10-spot ladybird including a chequered form and a black form with red bars at the front of the wing cases.

10-spot ladybirds are often found in deciduous trees where they feed on aphids. They are also found in a similar range of habitats to the 2-spot ladybird but less commonly.

Fact: This small ladybird is one of the most frequently confused with the harlequin ladybird but it so much smaller at about 4mm compared to harlequin ladybirds that can reach double that length.

Harlequin ladybird (Harmonia axyridis)

Harlequin ladybird (Harmonia axyridis). ©Gilles San Martin via Flickr

In 2004 the harlequin ladybird was first seen in the UK. It is a large aphid-feeding ladybird that had been introduced from Asia to many other countries as a biological control agent. Never intentionally introduced into the UK it arrived in many different ways including on produce. It varies in colour but there are three main forms found in the UK.

Orange with 0-21 black spots, black with two or four red spots. It is easily confused with a number of species but it has brown legs and often the pronotum bears a black ‘M’ shape on a white background.

Harlequin ladybirds favour the same habitats as 2-spot and 10-spot ladybirds – deciduous trees but they can be found feeding on aphids and other insects on many different plants including nettles.

Fact: Harlequin ladybirds often spend the winter months inside buildings and people sometimes report groups of 100s of individuals settled in the corners of windows and ceilings.

14-spot ladybird (Propylea quattuordecimpunctata)

14-spot ladybird (Propylea quattuordecimpunctata). © Gilles San Martin via Flickr

These yellow ladybirds have black square-shaped spots which often join with another and look like an anchor shape or clowns face. They can be confused with the chequered form of the 10-spot ladybird but the pronotum marking is very different: speckled ‘M’ shape on the 10-spot ladybird and a solid undulating shape which can look like a crown.

This aphid feeding species is commonly found on low growing vegetation and in crops.

Fact: 14-spot ladybirds are one of the last to emerge from their winter dormancy and have been described as the dormice of the ladybird world.

Cream-spot ladybird (Calvia quattuordecimguttata)

Cream-spot ladybird (Calvia quattuordecimguttata). ©Gilles San Martin via Flickr

The brown colour of the wing cases of the cream-spot ladybird deepen from orange to chestnut brown over time. Indeed it can be confused with the orange ladybird but the cream-spot has spots organised in rows.

Woodlands are the favoured habitat of cream-spot ladybirds but it can be found in gardens and other habitats too where it feeds on aphids and psyllids.

Fact: Cream-spot ladybirds spend the winter close to the ground in bark crevices but also in beech nuts and other cosy places.

Orange ladybird (Halyzia sedecimguttata)

Orange ladybird (Halyzia sedecimguttata). ©Gilles San Martin via Flickr

Orange ladybirds have a translucent edge to their wing cases and pronotum. Their cream spots are much more “splodgy” than the cream-spot ladybird. The spots of the orange ladybird are arranged in straight rows from the front to the rear of the ladybird rather than from side to side as for the cream-spot ladybird.

Orange ladybirds feed on mildew growing on the leaves of deciduous trees. Once considered an indicator of ancient woodland, orange ladybirds have expanded in range dramatically in recent decades and are found on trees in many different habitats.

Fact: Orange ladybirds develop more slowly than other ladybirds and it is not unusual to see orange ladybird larvae in early winter when most other species are dormant.

22-spot ladybird (Psyllobora vigintiduopunctata)

22-spot ladybird (Psyllobora vigintiduopunctata) in copula. ©Gilles San Martin via Flickr

The bright yellow and very spotty 22-spot ladybird is commonly found in gardens but also many other habitats with low growing vegetation. It has a very spotty pronotum alongside the spotty wing cases.

22-spot ladybirds feed on mildew and are regular visitors to plants such as courgettes in vegetable patches.

Fact: The male of the 22-spot ladybird often has a paler pronotum than the female.

24-spot ladybird (Subcoccinella vigintiquattuorpunctata)

24-spot ladybird (Subcoccinella vigintiquattuorpunctata). ©Gilles San Martin via Flickr

Deep red with black spots in various patterns and configurations this slightly hairy ladybird is easily recognised. It is a plant-feeding ladybird often seen in grasslands. Indeed sometimes the feeding damage on red campion or false oat-grass, whereby the ladybird has scraped the surface of the leaf away, can be an indication of the presence of this ladybird.

Fact: 24-spot ladybirds are widely distributed in England and Wales but have a very limited distribution in Scotland.

Pine ladybird (Exochomus quadripustulatus)

Pine ladybird (Exochomus quadripustulatus). ©Gilles San Martin via Flickr

Pine ladybirds are entirely black with four red markings – the front markings are comma-shaped. The rim around the edge of the wing cases can give the pine ladybird the appearance of a tiny bowler hat. These scale insect feeding ladybirds are found on many different plants despite their name suggesting an association with pine.

Fact: Pine ladybirds are amongst the first of the ladybirds to emerge from their winter dormancy. A welcome first sign of Spring.

Kidney-spot ladybird (Chilocorus renipustulatus)

Kidney-spot ladybird (Chilocorus renipustulatus). ©Gilles San Martin via Flickr

Kidney-spot ladybirds are closely related to pine ladybirds and have a similar overall shape but with only one red spot, centrally placed, on each wing case. This species can be found on many deciduous trees but is commonly associated with ash trees and can be easily observed when foraging for scale insects on the trunk or branches of ash trees.

Fact: Kidney-spot ladybirds have been observed using the rim around their edge to lift and prise scale insects from the surface of plants.

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