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Ladybirds for Biological Control of AphidsLadybird IdentificationOn this page: What are ladybirds? Are they useful or harmful? Subfamily Chilocorinae: Heather ladybird Malaysian ladybird Pine ladybird Subfamily Coccidulinae: Vedalia beetle Subfamily Coccinellinae: Two-spot ladybird Ten-spot ladybird Eyed ladybird Genus Anisosticta Water ladybird Larch ladybird Cream-spot ladybird Hieroglyphic ladybird Scarce seven-spot ladybird Five-spot ladybird Seven-spot ladybird Eleven-spot ladybird Harlequin ladybird Cream-streaked ladybird Adonis ladybird Eighteen-spot ladybird Striped ladybird Fourteen-spot ladybird Subfamily Scyminae: Mealybug ladybird Two-spot hairy ladybirdWhat are ladybirds?Ladybirds / ladybugs are neither birds nor (true) bugs (Hemiptera) but are species of smallish usually brightly-coloured predatory beetles in the family Coccinellidae. Different species of the family are found worldwide. The US for example has about 400 species (including 30 non-native), Australia has 260 native species, and 50-60 species are recorded from UK - including several presumed now extinct and several imports. Several ladybird species have been used for the biological control of insect pests.
Ladybirds are sometimes confused with other beetles, but most species can be readily distinguished using an ordinary 10x hand lens. Adult ladybirds (such as the one above) are 0.8 to 18 mm long. In many species the wing covers (elytra) are yellow, orange or red, often with contrasting spots. Some species are black, dark grey, gray, or brown. Whilst these patterns and colours can distinguish species, they often vary between members of the same species. Most coccinellids have round to elliptical dome-shaped bodies, dark legs, heads and antennae. The legs and antennae are short. Their tarsi are 3-lobed, the antennae are clubbed, and the palps are triangular and axe-shaped. Nearly all Coccinellids reproduce via sexually-produced eggs (see first picture below of eggs with a newly hatched larva). Their larvae undergo 4 instars - the larva in the second picture below is in the third instar. Larvae of most species have numerous tubercles and bristles - they can usually be identified to species by the time they reach the fourth instar. Larvae of some species are covered in white wax and look like mealybugs. The pupa (see third picture below) is attached to a leaf, and after 3-12 days the adult insect emerges.
Many species of ladybird hibernate, sometimes as large aggregations. Larval and adult Coccinellids have similar diets. Most ladybirds are insect predators, mainly eating aphids. They also eat scale insects (Coccoidea) and mealy bugs (Pseudococcidae), as well as insect eggs and pupae, including those of their own and other species of ladybirds. Coccinellids will also eat nectar, honeydew, pollen, fruit, vegetation, and fungus - which increase survival when prey is scarce, reduce mortality during diapause, fuel migration, and enhance reproduction. Are they useful or harmful?Ladybirds, known as ladybugs in USA, are generally seen as useful insects since most species are predatory on various insect pests. Various species such as the harlequin ladybird (Harmonia axyridis, see picture at top of page) have been introduced or mass-released to control aphids, scale insects, mealybugs, and even spider mites (Tetranychidae). That said - a few ladybird species such as the Mexican bean beetle (Epilachna varivestis) eat plants and can be pests, whereas others such as Halyzia sedecimguttata (see picture below) eat mildew.
Some ladybird species that have been introduced, either intentionally or unintentionally (via imported plants), have become 'invasive' - but what, if any, damage they cause to other ladybird species is debatable. Ladybirds occasionally nip people, but are generally harmless to large animals including humans. They also don't seem to be poisonous to humans, but they taste foul, and their conspicuous aposematic coloration warns predators such as birds to avoid them. LADYBIRD IDENTIFICATIONThe coccinellid family contains 6000 species, comprising 360 genera (e.g. see Wikipedia) somewhat arbitrarily divided into 7 or 8 subfamilies. Most of the predatory species are in four subfamilies - the Chilocorinae, the Coccidulinae, the Coccinellinae and the Scyminae - and we concentrate on these in the page below. Subfamily ChilocorinaeThe Chilocorinae are helmet-like in appearance with a flared rim, often black with red or orange spots. Their larvae have been described as 'dumpy elongate' and have long, multi-branched spikes. Members of this subfamily feed predominantly on scale insects. Chilocorus bipustulatus (Heather ladybird)The heather ladybird (Chilocorus bipustulatus) is a rather small coccinellid with a body length of 3-4 mm. The elytra are shiny dark reddish-brown to black, usually with a total of 6 red spots in a line across the middle of the elytra (see first picture below). Spot fusions may reduce this to 4 or 2 red spots. The pronotum and head are black, as are the legs. There is a distinct rim around the edge of the elytra.
Second and third images above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 License. The fourth instar larva of Chilocorus bipustulatus (see second picture above) is mostly blackish brown apart from a diagnostic pale first abdominal segment. Each thoracic and abdominal segment bears six long spines which give rise to hairs with extensive side branching. The spines are black except for those on the first abdominal segment which are pale. The pupa of Chilocorus bipustulatus (see third picture above) is shiny black with numerous hairs. The old larval skin remains around the lower part of the pupa. Chilocorus bipustulatus seems to favour xeric habitats - in Britain it is mainly found in heathland, coastal dunes and scrub; in mainland Europe it inhabits pine forests, orchards and stone quarries. It is a coccid (='scale insects') specialist, feeding especially on soft scales (Coccidae) and armoured scales (Diaspididae), as well as aphids when available. It has been used in several classical biological control programmes for control of scale insects in olive groves in America, and palm scales in West Africa; it has also been used for augmentative releases in olive groves in Greece. Chilocorus bipustulatus is found in most of the Palaearctic zone, and has been introduced for biological control purposes to tropical Africa, Hawaii and North America. Chilocorus nigritus (Malaysian ladybird)Chilocorus nigritus is a small, almost hemispherical coccinellid with a body length of about 4mm (see first two pictures below). The head is dull orange yellow. The pronotum is dark brown to black in the middle, paler on the sides with orange-yellow anterolateral flaps. The elytra are shiny black with fine punctations. The underside of Chilocorus nigritus is orange-yellow to yellowish-brown. The outer, folded, margins of the elytra are dark brown to black.
First image copyright Natural History Museum under a Creative Commons Attribution-NonCommercial 3.0 Unported License. The Chilocorus nigritus larva (see third picture above) is yellow-brown to whitish with numerous spiny, branched protruberances on the dorsal side. Chilocorus nigritus is a predator of scale insects, especially armoured scales (Diaspididae). The species is native to SE Asia, but has been used for classical biological control with introductions in Hawaii and parts of Europe. It is also widely used for augmentative releases in greenhouses. Exochomus quadripustulatus (Pine ladybird)Adult Exochomus quadripustulatus are quite small, approximately circular and with a flange around the edge of each elytron. The commonest form is black with two red comma-like spots at the front of the elytra and two roundish red spots nearer the midline towards the back of the elytra. The spots may also be orange or yellow, and there is also a completely reddish-brown form. The prothorax and head of the pine ladybird are black.
Second image copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. The fourth instar larva of Exochomus quadripustulatus (see second picture above) is grey with branching black spines topped with short bristles. The prothoracic and mesothoracic dorsal tubercles are black with orange markings. There is also a conspicuous light orange patch on and around the dorso-lateral tubercle of the first abdominal segment. Exochomus quadripustulatus feeds on scale insects, adelgids and aphids. Although the pine ladybird is the commonest species found on pine, it is also found on many other trees and plants and in a variety of habitats. The pine ladybird is widely used as a biocontrol agent, both for augmentative releases and as a component in an integrated control programme, for several species of Pulvinaria scale insects. It is found over most of Europe. Subfamily CoccidulinaeThe Coccidulinae all have pubescent adults and most are red, brown or black. Their larvae are flattened and covered with tubercles. They mainly feed on scale insects. Rodolia cardinalis (Vedalia beetle)Rodolia cardinalis is a rather small ladybird, about 2.5-4 mm long, which is covered with dense, short hairs. The elytra are reddish brown with a total of five black spots, two on each elytron and one on the suture, extending down the suture to the posterior edge (see first picture below). These spots are often merged together to form an irregular black patch (see second picture below). The head, most of the prothorax and the scutellum of Rodolia cardinalis are black, while the legs and antennae are mainly reddish.
First images above copyright Maurice under a Creative Commons Attribution-Share Alike 2.0 Generic License. The fourth instar larva of Rodolia cardinalis (see third picture above) is about 5 mm long. The body is orange-red to reddish purple The dorsal and dorso-lateral tubercles are black, but the ventro-lateral tubercles are reddish. All tubercles bear short bristles. The prothorax and head are red. Rodolia cardinalis generally has a very narrow host-range, being restricted to just a few species of scale insects in the Coccidae (soft scales) and Margarodidae (cottony cushion scales). However, if its usual prey are scarce, it may take other scale insects, aphids and mites. The Vedalia beetle is native to Australia, but now has a world wide distribution due to its widespread use in classical biological control operations against (primarily) the cottony cushion scale (Icerya purchasi). As such it has proved invaluable in classical biological control operations outside its natural range, the first such operation being its introduction to California in the late 19th century for control of cottony cushion scale on citrus (see Caltagirone & Doutt (2004)). It is mostly found in warmer climates, but has been found in cooler climes (see for example Salisbury & Booth (2004) who found it feeding on Icerya purchasi in London gardens). Subfamily CoccinellinaeThe Coccinellinae adults are round or elliptical and are usually aposematically coloured. They include many common species (e.g. Adalia bipunctata & Harmonia axyridis), and have dark, often brightly-marked, crocodile-like larvae. They mainly feed on aphids. Adalia bipunctata (Two-spot ladybird)The typical form (f. typica, see first picture below) of the adult two-spot ladybird has red elytra with a large black spot in the middle of each. The prothorax is black with a large white patch on each side and a small white patch on top. The black head may also have two small white spots. The 4-spot melanic form of Adalia bipunctata (form quadripustulata, see second picture below) is black with four red spots. The 6-spot melanic form (form sexpustulata, see third picture below) is black with sex red spots. Melanic forms of the 2-spot ladybird also have reduced white areas. The elytra are smooth before the tip (cf. the 10-spot ladybird, Adalia decempunctata in which the elytra have a transverse groove before the tip). The underside and the legs of Adalia bipunctata are black (cf. Adalia decempunctata which has brown legs).
Second image copyright Olei under a Creative Commons Attribution-Share Alike 2.5 Generic license. Fourth instar larvae of Adalia bipunctata (see picture below) have conspicuous orange to whitish tubercles on the first abdominal segment, and a pair of orange dorsal tubercles on abdominal segment four. The yellow associated with the dorsal tubercles on segment four may be restricted to the area between the tubercles. There are further orange to whitish spots down the dorsal midline and laterally on abdominal segment four. The outer tubercles on abdominal segments 5-8 are dark (cf. Adalia decempunctata which has those tubercles pale). Third instar larvae are grey-black with orange to whitish areas on the lateral apical margin of the pronotum and on the dorsolateral tubercles of the first abdominal segment; first and second instar larvae are black to grey with no coloured areas.
The two-spot ladybird is a widespread and common species which occupies a variety of habitats from mature lime or sycamore trees, to deciduous or coniferous woodland, orchards and crops. It is not normally reared for release for biological control, but is important in the natural biological control of many aphid species. Adalia bipunctata is found throughout Europe, Asia (excluding the Indian subcontinent and Southeast Asia) and North America. Adalia decempunctata (Ten-spot ladybird)The ten-spot ladybird, Adalia decempunctata is a rather small almost round ladybird with body length 3.5-4.5 mm. The elytral colour and pattern is very variable, but there are three main forms all of which occur commonly: The 'typical' form ('decempunctata', see first picture below) has a red, orange or brown ground colour and between 0 and 12 distinct black elytral spots. The chequered form (decempustulatus, see second picture below) has a buff, beige or light brown ground colour overlaid with a dark grid-like pattern. The melanic form (bimaculata, see third picture below) has a dark brown or black ground colour with two red, orange or yellow shoulder flashes. In freshly hatched Adalia decempunctata the elytra are pale brown. The colour of the pronotum varies between white with five darker spots, and black with narrow white edges. The head is black basally and pale anteriorly, sometimes with contrasting spots. The ten-spot ladybird legs are orange, and its abdomen underside is yellow or orange.
Second image above copyright Boris Loboda under a under a CC BY-NC-ND 3.0 creative commons licence. The larva of Adalia decempunctata (see picture below) is mainly grey, but with pale dorsal areas on the thoracic segments and a light brown head. It also has a pair of conspicuous pale orange to whitish dorsolateral tubercles on the first abdominal segment, a pair of mid-dorsal pale tubercles on abdominal segment IV and partially or completely pale outermost lateral tubercles on most abdominal segments (cf Adalia bipunctata which has the latter tubercles dark). Adalia decempunctata also has fine hairs projecting from the tubercles.
Image above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. The ten-spot ladybird mainly feeds on aphids, and occasionally scale insects and mites. It also takes pollen and nectar. It is a primarily an arboreal species found especially on broad-leaved trees, but may also be found on conifers, in hedgerows and on low-growing herbs such as stinging nettles. The ten spot ladybird has not been used for augmentative releases, but has been found to be an important predator in controlling tree aphid pests such as the walnut aphid Chromaphis juglandicola. Like the two-spot ladybird, the ten-spot ladybird can be found in any vegetation type, but seems to show a preference for trees, shrubs and bushes. Adalia decempunctata is found throughout the Palaearctic region in Europe, North Africa, European Russia, the Caucasus and most of Western Asia. Anatis ocellata (Eyed ladybird)The adult Anatis ocellata (eyed ladybird) has a variable number of black spots (usually 15-18, but may be 0-23) on a red background. Each spot is surrounded by a yellowish halo. The pronotum is black with a thick white U-shaped mark and two small white spots. The antennae are brown, and the legs are black and brown. Anatis ocellata is a large coccinellid, with a body length of 7-8.5 mm.
Second image above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 3.0 License. The fourth instar larva (see second picture above) is grey-black and conspicuously spiny. It has a medial orange area between the tubercles on the head and prothorax, and orange dorsolateral tubercles on the first and second abdominal segments. There are also whitish or orange spots along each side of the thoracic and abdominal midlines. Both larval and adult eyed-ladybirds mainly feed on aphids on pine trees, especially the waxy grey pine needle aphid (Schizolachnus pineti), and are thought to be involved in the natural biological control of various aphid conifer pests. They are often reported to also feed on adelgids but we have not observed this. Anisosticta novemdecimpunctata (Water ladybird)Anisosticta novemdecimpunctata is about 3.5-5 mm in body length, distinctly elongate and flattened in shape. The elytra are buff or beige for most of the year (see first picture below), but from April-June they adopt a reddish hue (see second picture below). They bear fifteen to twenty-one black spots, most commonly nineteen spots as in the pictured specimens. The pronotum is buff or beige with six black spots, rounded at the sides with the greatest width in the middle. The legs of Anisosticta novemdecimpunctata are pale brown.
First two images above copyright Gilles San Martin under Creative Commons Attribution-Share Alike 2.0 Generic licenses.
The fourth instar larva of Anisosticta novemdecimpunctata (see third picture above) has the thoracic region cream or white with dark patches. The abdomen is pale grey with alternating rows of black and white tubercles running longitudinally, and fine hairs projecting from the tubercles. Anisosticta novemdecimpunctata is found in wetlands on marsh- and water-plants such as reeds (Phragmites) and sedges (Carex species) where it contributes to the natural biological control of various waterside aphids, such as Hyalopterus pruni and Rhopalosiphum nymphaeae. Anisosticta novemdecimpunctata doubtless itself falls prey to various avian predators, like the reed warbler, which also feed on the waterside aphids. The water ladybird is found throughout the West Palaearctic, from Western Europe to Middle Asia. Aphidecta obliterata (Larch ladybird)Adult larch ladybirds (Aphidecta obliterata) are elongate oval in shape and are usually light tan brown in colour. They have a dark oblique patch of variable size on the rear third of each elytron and various other small blotches and spots (see first picture below). The oblique patch is sometimes completely absent (see second picture below). There are other colour varieties of Aphidecta obliterata, including one with entirely black elytra. The suture (where the elytra meet) is darkened. The pronotum is whitish beige with a brown W mark. The legs are brown.
Second image copyright S. Rae under a Creative Commons Attribution-Share Alike 2.0 Generic license. The fourth instar larva of Aphidecta obliterata (see third picture above) is light grey with dark grey tubercles. The marginal and lateral tubercles of abdominal segment 1 are orange. The tubercles bear rather short hairs with no spines. Aphidecta obliterata is found on conifers, especially larch (Larix), but also spruce (Picea), pines (Pinus) and firs (Abies). There it feeds on aphids and (perhaps less readily) on adelgids. It overwinters in bark crevices. The larch ladybird was successfully introduced into America for the biological control of Adelges piceae, but unfortunately it failed to give an acceptable level of control. This coccinellid is found throughout Europe and into Asia Minor, and has been introduced into North America. Calvia quattuordecimguttata (Cream-spot ladybird)Calvia quattuordecimguttata is a medium-sized ladybird ranging in length from 4.0-5.5 mm. In Europe the elytra are consistently maroon-brown with fourteen cream-coloured spots. In North America and parts of eastern temperate Asia other varieties also occur. Calvia quattuordecimguttata may be black with white spots, or yellow to pink with eighteen large blotches. Another variety is black with a large red spot on each elytron. The cream spot ladybird underside is black surrounded by a thin red rim.
The Calvia quattuordecimguttata larva is dark grey with pale areas on the dorsum of the thoracic segments and on the head. There is a pair of pale dorsolateral tubercles on abdominal segment I, six pale tubercles across segment IV and pale lateral tubercles bearing tubular papillae on segments IV to VII. The larva has medium length unbranched conical spines on every abdominal segment. The preferred prey of the cream spot ladybird is aphids, but like many coccinellids it will take other prey when available especially psyllids, but also scale insects, mites and even the eggs and larvae of Lepidoptera. Calvia quattuordecimguttata is found in a wide variety of habitats, but is especially characteristic of deciduous broadleaved woodlands, hedges, orchards, parks and gardens. The cream spot ladybird makes an important contribution to the natural biological control of aphid and psyllid pests in gardens and orchards. It is widely distributed being found throughout Europe, most of Asia (but excluding the Indian subcontinent, south-east Asia and the southern Arabian peninsula) and most of North America. Coccinella hieroglyphica (Hieroglyphic ladybird)Coccinella hieroglyphica is a medium-sized coccinellid with a body length of 4-5 mm. The elytral background colour is light brown (rarely chestnut-brown), with a pattern of black stripes, spots and patches (see first picture below). These sometimes form a black hieroglyph-like mark giving the ladybird its name (see second picture below) and melanic (=dark) forms also occur (see third picture above). The pronotum is black with antero-lateral white patches, and the head is black with two small white patches. The legs of Coccinella hieroglyphica are black.
First and third images above copyright S. Rae under a Creative Commons Attribution-Share Alike 2.0 Generic license.
The fourth instar larva of Coccinella hieroglyphica (see picture below) is dark grey-black with mostly black tubercles. There are pale yellow patches in the centre of the meso- and metathoracic segments, and the dorso-lateral and ventro-lateral tubercles on the first and fourth abdominal segments are pale yellow.
Image above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. Coccinella hieroglyphica is found on heathland, often where it has been invaded by scrub, and on acid grassland, marshes and mixed forests. It is often associated with heather (Calluna vulgaris), less frequently with pine and birch. It feeds on the heather aphid (Aphis callunae), and contributes to the natural biological control of that species. It also feeds on aphids on willows, birches and alder, as well as leaf beetle eggs and larvae. The hieroglyph ladybird is found through much of the Palaearctic zone, from Western Europe to the Russian Far East, and from beyond the Polar circle to northern Italy. It is also found in North America as Coccinella hieroglyphica mannerheimi. Coccinella magnifica (Scarce seven-spot ladybird)Coccinella magnifica is a medium-sized to large ladybird at 6-8 mm in length. The elytra are mainly red, but with a small whitish area near the anterior border. There is usually a total of seven black spots, although five to eleven are recorded (see first two pictures below). The central spots are comparatively large and the foremost spots are comparatively small. The pronotum is black with antero-lateral white marks. The legs of Coccinella magnifica are black. There are small white triangular marks on the underside, below both the middle and front legs (cf. Coccinella septempunctata, which has such marks only below the middle legs).
First two images above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. The larva (not pictured) is similar in appearance to that of Coccinella septempunctata. It is dark grey black with mostly black tubercles. There are pale orange-yellow lateral patches on the prothorax, the sides of the meso- and metathorax are pale grey, and the dorso-lateral and ventro-lateral tubercles on abdominal segments one and four are orange-yellow. Coccinella magnifica is possibly the only truly myrmecophilous coccinellid (Sloggett et al., 2002) see below. Coccinella magnifica is usually found in woodland and heathland close to wood ant (Formica spp.) nests. The adults and larvae are predators of aphids, scale insects, mites, and insect eggs. They are most commonly found on Scots pine trees, where they have been observed feeding on Cinara pinea, Cinara pini and Schizolachnus pineti. They have been recorded predating other aphid species, including Cinara piceicola, Cinara pilicornis and Elatobium abietinum on spruce, Aphis sarothamni on broom, Aphis salicariae on rosebay willowherb, and Aphis ulicis on gorse, all of which are often tended by Formica rufa (see third picture above) or may have the ants gleaning the aphid honeydew from surrounding vegetation. Coccinella magnifica is found throughout north-western Europe and into central Europe. Coccinella quinquepunctata (Five-spot ladybird.htm)Coccinella quinquepunctata is a medium-sized, quite rounded, domed ladybird with an adult body length of 3-5 mm (see first two pictures below). The elytra are red with a pair of large central black spots, two smaller postero-lateral spots and a single large black spot on the scutellum, the latter partially bordered with white patches. Rarely there may be up to four additional small spots. The pronotum is black with two antero-lateral white marks. The Coccinella quinquepunctata head is black with two small white marks.
First two images above in public domain, copyright pudding4brains under a Creative Commons Attribution-NonCommercial 1.0 Unported License. The fourth instar larva of Coccinella quinquepunctata is dark grey with mostly black tubercles. There are bright orange lateral patches on the prothorax, and the ventro-lateral tubercles on the metathorax are orange. There are also orange patches on the dorso-lateral and ventro-lateral tubercles on the first and fourth abdominal segments and on the dorsolateral tubercles of the sixth and seventh abdominal segments. Coccinella quinquepunctata is found through most of Europe including Norway and Sweden, but there seems to be little information available on its distribution outside of Europe. In Britain they are restricted to vegetation on unstable river shingle. In continental Europe they occur in more varied habitats. The five-spot ladybird feeds on aphids on nettles, thistles and other low plants. Coccinella septempunctata (Seven-spot ladybird)Coccinella septempunctata is a fairly large ladybird (5.2-8.6 mm), oval in shape and strongly convex. The head is black with a pair of semicircular white frontal spots, one on either side of the inner margin of the eyes. The pronotum is black, with a pale yellow or white antereolateral spot. The ground colour of the elytra is usually red or orange (see first two pictures below), rarely yellow. The typical elytral pattern is seven black spots: there is one common spot around the scutellum, and three on each elytron with small white patches on either side of the scutellum, just above the scutellar spot. The size of the spots is highly variable. The underside of Coccinella septempunctata is more or less completely black.
The fourth instar larva of Coccinella septempunctata (see third picture above) is dark grey-black with mostly black tubercles. The sides of the meso- and metathorax are pale grey, but there are orange lateral patches on the prothorax (cf. Coccinella undecimpunctata which lacks the orange lateral patches on the prothorax). The dorso-lateral and ventro-lateral tubercles on abdominal segments one and four are orange. Coccinella septempunctata is a common species occurring in many different habitats including gardens, grassland, and broad-leaved and mixed forests. The seven-spot ladybird is mainly aphidophagous, but also feeds on thrips (Thysanoptera), white flies (Aleyrodidae) and the eggs and larvae of other insects. There are one or two generations a year. The adults overwinter in sheltered sites often in large aggregations. The seven-spot ladybird has been widely used in classical biological control programmes as well as for augmentative releases and conservation biological control. Its introduction to the USA is, however, controversial because of possible adverse effects on the local fauna. Augmentative releases have provided effective control in 'protected' environments (glasshouses etc), but not outdoors. Most emphasis now is put on integrated control whereby the aim is to use selective insecticides so as to conserve the natural coccinellid populations. Coccinella septempunctata is found throughout Europe, North Africa and most of Asia, and has been introduced to North America and South Africa. Coccinella undecimpunctata (Eleven-spot ladybird)Coccinella undecimpunctata is medium-sized ladybird with a body length of 4-5 mm. The elytra are red, usually with 11 black spots (see first picture above), but the small front spots may become very small, almost invisible. The pronotum is black with antero-lateral white marks.. The head is black with two white dots (see second picture above). The underside and the legs of Coccinella undecimpunctata are black.
Third image above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. The fourth instar larva (see third picture above) of Coccinella undecimpunctata is similar to that of Coccinella septempunctata in that it is grey-black with orange dorso-lateral and ventro-lateral tubercles on abdominal segments one and four. However, it lacks the conspicuous orange patches on the prothorax which are characteristic of the larva of the seven-spot ladybird. Coccinella undecimpunctata is found in many habitat types with low growing vegetation, but is especially characteristic of coastal and estuarine habitats such as dune systems and salt marshes. It feeds on aphids, especially grassland and herb species. It has been used for classical biological control programmes in Australia and New Zealand, and for augmentative biological control, for example for control of Aphis gossypii and Myzus persicae on cucumber crops (Abd El-Gawad & El-Zoghbey, 2009) . It is native to Europe, Asia and North America, but has been introduced to Australia and New Zealand Harmonia axyridis (Harlequin ladybird)Harmonia axyridis is a relatively large species, around 6-8 mm long. Harlequin ladybirds are highly variable both in terms of colour and pattern. The commonest forms of Harmonia axyridis (at least in Europe) are shown below. Form succinea (see three pictures below) has red or orange elytra with 0 - 21 (usually 15-21) black spots. The pronotum is white or cream, with a thick black M marking which may be broken into black spots.
Harmonia axyridis form spectabilis (see first picture below) has black elytra with 4 red spots, and a white or cream pronotum with a solid black trapezoid central portion. Form conspicua (see second picture below) has black elytra with 2 red spots which each have a black spot within them, and a white or cream pronotum with a solid black trapezoid central portion. The elytra usually have a wide keel at the back and the legs and underside are almost always brown.
The fourth-instar larva of Harmonia axyridis (see third picture above) is black with conspicuous orange markings. The bases and spines of the lateral tubercles on abdominal segments I-V are yellow-orange, as is the pair of dorsal tubercles on abdominal segment, making an orange L-shape on each side. The pairs of dorsal tubercles on abdominal segment IV and V bear a total of four orange spines (cf. the larva of Harmonia quadripunctata which has only two of orange spines towards the rear). Harmonia axyridis is most commonly found on deciduous trees and on low growing vegetation. The harlequin ladybird is a voracious predator of aphids and scale insects. It also eats the eggs and larvae of other insects, including other ladybird species. The adults and larvae are also cannibalistic, consuming the eggs and smaller larvae of their own species. An immense amount has been written about the harlequin ladybird, much of which is covered in the review by Koch (2003). The Harlequin ladybird is native to eastern Asia, but has been introduced for biological control purposes to various European countries, the United States and South Africa. Harmonia axyridis has since proved to be highly invasive - in Britain it took Harmonia axyridis just two years to spread from East Anglia to Devon (Brown et al., 2008) - and now has a cosmopolitan distribution. Harmonia quadripunctata (Cream-streaked ladybird)The cream-streaked ladybird, Harmonia quadripunctata, is a very variable species. The 'typical' form of this ladybird (see first picture below) is bright red with 16 or 18 black spots, and streaked with cream. But in many specimens, most of the black spots are missing (see second picture below), leaving only the four marginal spots, two on each side. This form gave the name 'quadripunctata' to the species. The elytra usually have pale outer edges. The pronotum is white with a fairly consistent pattern of black markings, 7 of which are large and bold. The underside of Harmonia quadripunctata is dark with orange-brown sides.
Second image copyright entomart. The fourth-instar larva (see third picture above) is black, with thick dorsal spines coming from each tubercle, each branching from the base into three prongs. It has a bright orange line on each side, made from orange spots on the dorsolateral tubercles of abdominal segments one to four. There is one pair of orange dots on the inner dorsal tubercles on abdominal segment four. The cream-streaked ladybird is the most common large ladybird found on conifers, usually Scots pine, but also exotic pines, Douglas fir and Norway spruce, where it feeds on aphids. They may occasionally be found on herbaceous plants and shrubs such as nettle and gorse, but these are usually situated close to conifers. The species is important in the natural biological control of aphids on conifers, and has also been found predating Brachycaudus amygdalinus in almond and peach orchards in Syria. Harmonia quadripunctata is widespread from northern to southern Europe and in the eastern Palearctic and the Near East. They have also been found occasionally as vagrants in eastern North America, and may well be established in Massachusetts. Hippodamia variegata (Adonis ladybird)Hippodamia variegata is a small ladybird of length 4-5 mm with a somewhat elongated, oval shaped body. The elytra are red with 3-15 black spots, most commonly nine concentrated to the rear (see first two pictures below). One black spot on the scutellum is partially surrounded by white patches. The prothorax is black with a partial white-yellowish border, and two white spots towards the front. The head of Hippodamia variegata is black with white frontal spots. The femora of the legs are black, but the tibiae and tarsi are brown (cf. Coccinella septempunctata which has entirely black legs).
Third image above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. The fourth instar larva of Hippodamia variegata is grey with the tubercles entirely black, except for the dorso-lateral and ventro-lateral tubercles on abdominal segment I which are yellow-orange (see third picture above) (note: we cannot be too certain about the colour pattern of the larva as the available photos are mutually inconsistent). The larva shown is only third instar, but it does not appear to differ from the fourth instar in coloration. .Hippodamia variegata is mainly aphidophagous, but also eats thrips, whiteflies, scale insects and mites. The Adonis ladybird is mainly found on plants growing in xeric habitats, such as those on sandy, open soils or derelict industrial sites. Our pictures above were taken on a shingle beach. It has been reported as an important natural enemy in a diversity of crops of at least 12 different aphid species, including major pests such as the cotton aphid (Aphis gossypii) and the pea aphid (Acyrthosiphon pisum). Hippodamia variegata is native to the Palaearctic, but is now found much more widely, partly by natural spread (e.g. in Australia), and partly through introductions for biological control (e.g. in Chile for control of the cereal aphids Metopolophium dirhodum and Sitobion avenae). Myrrha octodecimguttata (Eighteen-spot ladybird)Myrrha octodecimguttata is a medium-sized elongate-oval shaped ladybird ranging in length from 4.0-5.0 mm. The typical form (see first picture below) has the elytra maroon-brown with sixteen-eighteen creamy white spots, but the spots are sometimes merged together (see second picture below). The pronotum is also brown and has conspicuous whitish sides and white spots on the anterior and posterior edges. The white markings result in a characteristic rounded brown 'M' mark on the pronotum. The Myrrha octodecimguttata head is brown with two white marks.
All three images above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic License. The larva of Myrrha octodecimguttata is light grey. The tubercles are mostly black, except for the dorsolateral and ventrolateral tubercles on the first abdominal segment which are bright orange. Myrrha octodecimguttata is found in coniferous and mixed deciduous/coniferous woodland, especially in pine trees, living in the upper canopy. In northern areas it also occurs on high bogs. It feeds on conifer aphids. Nunez-Perez & Tizado (1996) recorded Myrrha octodecimguttata as a predator of both Cinara pinea, Eulachnus rileyi and Schizolachnus pineti in the León province (Spain). It is distributed from Europe eastwards over most of the Palearctic zone Myzia oblongoguttata (Striped ladybird)Myzia oblongoguttata is brown or chestnut coloured with cream stripes and spots (see first picture below). The pronotum is similarly coloured (sometimes darker) with a large white patch anterolaterally on each side (see second picture below). The head of Myzia oblongoguttata is black with a cream patch between the eyes.
Third image above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. Fourth instar larvae of Myzia oblongoguttata (see third picture above) have an orange patch at the front of the pronotum. Most of the body tubercles are black but there is a pair of conspicuous orange dorsolateral tubercles on the first abdominal segment, and orange ventro-lateral tubercles on abdominal segments one, four and six. Myzia oblongoguttata mainly occurs in coniferous and mixed forest, but can also be found in birch forest. They feed on aphids, especially species in the genus Cinara. Cinara aphids are usually ant-attended, so striped ladybirds have evolved to be more tolerant of ant attacks than most coccinellids - albeit not as ant tolerant as Coccinella magnifica, which is a true myrmecophile. Myzia oblongoguttata overwinter under loose bark and in ground litter. Striped ladybirds are involved to a greater or lesser in the natural control of Cinara aphids, but have not as far as we know been used for augmentative biological control. The species is distributed throughout the Palaearctic zone. Propylea quattuordecimpunctata (Fourteen-spot ladybird)Propylea quattuordecimpunctata is a medium sized coccinellid, 2.5-5 mm in length. The elytra are yellow (rarely cream or orange), each nominally with seven black spots (see first picture below), although these are often partially fused (see second picture below) or completely fused (see third picture below). There is also a rare melanic (=dark) - form merkeri. The pronotum is yellow with a large black patch which has four anterior projections, rarely as four distinct spots. The head of Propylea quattuordecimpunctata is yellow with the eyes black; males have a solid yellow 'face', females have a dark spot in the middle.
The Propylea quattuordecimpunctata fourth-instar larva (see fourth picture above) is grey-black with yellow markings. The prothoracic dorsum and most of the tubercles are grey-black, but there is a mid-dorsal row of pale yellow patches running from the mesothorax to the last abdominal segment - the patches are large on the meso and metathorax, and smaller on the abdominal segments except for a larger patch on segment IV. The pair of dorsal tubercles on abdominal segment IV, the dorso-lateral tubercles on segments I and IV, and most of the ventro-lateral tubercles are yellow. The head is mainly pale.
Fourth image above copyright Gilles San Martin under a Creative Commons Attribution-Share Alike 2.0 Generic license. Propylea quattuordecimpunctata does not show a preference for any particular habitat, being found in broad-leaved and coniferous woodlands, meadows, moorlands and so on. It feeds mainly on aphids, and we have found it feeding on several species including Periphyllus on sycamore and Chaitophorus populeti on white poplar. The fourteen-spot ladybird will also take coccids, aleyrodids and insect eggs. It has not as far as we know been used for augmentative biological control in Europe, but in North America attempts were made to introduce as part of a 'classical biological control' programme. Repeated unsuccessful attempts were made prior to the 1960s, but it then became established in North America following an accidental introduction via European shipping. By the 1990s it was recorded in nine states in the USA. Further releases were then made for control of the Russian wheat aphid (Diuraphis noxius) in the USA, but these were not thought to have resulted in any more established populations. The natural distribution of Propylea quattuordecimpunctata extends throughout the Palearctic zone. Subfamily ScyminaeThe adult Scyminae are much less conspicuous than most coccinellids being usually small and brown or black. The elongate body shape of the larva is disguised by a series of fleshy protuberances usually covered with white wax. They feed upon aphids, coccids, mites or mealybugs, usually specializing on just one group. Cryptolaemus montrouzieri (Mealybug ladybird)Adult Cryptolaemus montrouzieri are medium-size coccinellids, measuring up to 6 mm in body length. Their elytra are rather uniformly dark brown and covered with fine hairs which can give them a silvery appearance. The head, antennae, pronotum, legs and the tips of the elytra (as well as the tip of the abdomen that protrudes beyond the elytra) are orange-brown.
First image above copyright gbohne under a Creative Commons Attribution-Share Alike 2.0 Generic license. The fourth instar larva of Cryptolaemus montrouzieri (see second picture above) is much larger than the adult (and than the mealybugs it feeds on) with a body length of up to 13 mm. The larva has 'appendages' of white flocculent wax which make it appear like its prey, an example of 'aggressive mimicry' which prevents it being identified by prey and other predators alike. Cryptolaemus montrouzieri is a voracious predator of mealybugs and has been widely introduced for biological control. When prey are scarce they also feed on aphids and soft scales. It has been used for classical biological control, for example when it was introduced to California in 1891 to control the citrus mealybug (Planococcus citri). That species is endemic to Queensland and New South Wales in Australia, but has been introduced to many parts of the world where it has become established - including southern Europe, tropical and North Africa, parts of North America and the Neotropical zone. Scymnus frontalis (two-spot hairy ladybird)Scymnus frontalis is a small coccinellid with a body length of only 2.6-3.2 mm. The elytra are black and covered with fine hairs. They usually have two elongate dull red spots towards the front of the elytra which do not extend to the margin of the elytra (cf. Scymnus interruptus which has two orange-brown spots on the elytra which reach the edge of the elytra and then extend along the edge towards the border with the pronotum). There is also a form with four red spots. The pronotum is completely black in the female, but has reddish brown margins in the male. The Scymnus frontalis head is black in the female and brown in the male (cf. Scymnus schmidti which has the head of both sexes reddish-brown). The mouthparts and legs are brown.
The Scymnus frontalis larva is covered with white waxy tufts. Unfortunately the larvae of the different Scymnus are not distinguishable (at least we can find no detailed morphological descriptions of the larvae of the various species under the wax), so our pictures of the larvae above and below that we have found predating aphids may be of any of the UK Scymnus species. Scymnus frontalis was imported from Turkey into the United States as a potential predator of the Russian wheat aphid, Diuraphis noxius (Naranjo et al. (1990). Diuraphis noxius lives inside characteristically rolled leaves, refugia which both larvae and adults of Scymnus are able to penetrate. However, the temperature threshold for development of Scymnus frontalis was about 5-10°C higher than that of Diuraphis noxius. Subsequent work by Gibson et al. (1992) to evaluate its potential showed that Russian wheat aphid was a very suitable prey for Scymnus frontalis, which showed a slight preference for Russian wheat aphid over the English grain aphid (Sitobion avenae). Scymnus frontalis was subsequently released in the USA and became established, but it is unclear how effective the control has been. In Britain we have only found Scymnus adults on one occasion (see pictures above), but have found Scymnus larvae quite frequently. Some observations have been from coniferous woodland where the most likely species are Scymnus nigrinus (adult has upper surface completely black, with the legs also completely black) and Scymnus suturalis (adult has mainly brown elytra, but with black along the front margin and the suture).
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_adult_Schulzew.jpg "Rodolia cardinalis (vedalia beetle) adult (merged spots); Katja Schulz")
_Kirillovew.jpg "Adalia bipunctata f. sexpustulata (melanic two-spot ladybird) from St. Petersburg, Russia; Pavel Kirillov")
_Rae_(4)ew.jpg "Aphidecta obliterata (larch ladybird) adult at Muir wood, East Lothian, Scotland; S. Rae")
_larva_GSMew.jpg "Coccinella hieroglyphica (hieroglyph ladybird) larva in Belgium; Gilles San Martin")
ew.jpg "Coccinella undecimpunctata (eleven-spot ladybird) larva; Gilles San Martin")
_GSMew.jpg "Harmonia quadripunctata larva, Namur, Belgium, 1 October 2012; Gilles San Martin")
_GSMew.jpg "Myrrha octodecimguttata (eighteen-spot ladybird) adult; Gilles San Martin")
_pale_adult_GSMew.jpg "Myrrha octodecimguttata (eighteen-spot ladybird) adult pale form from Spain on 26/5/10; Gilles San Martin")
ew.jpg "Cryptolaemus montrouzieri (mealybug ladybird) adult in Tangerang, W. Java, Indonesia on 22/11/10")
