Coccinellidae

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Ladybird
Coccinella magnifica
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Suborder: Polyphaga
Superfamily: Cucujoidea
Family: Coccinellidae
Latreille, 1807 [1]
Subfamilies [1]

The Coccinellidae are a family of small beetles, ranging from 0.8 to 18 mm (0.0315 to 0.708 inches).[3] They are commonly yellow, orange, or scarlet with small black spots on their wing covers, with black legs, heads and antennae. Such colour patterns vary greatly, however; for example, a minority of species, such as Vibidia duodecimguttata, a twelve-spotted species, have whitish spots on a brown background. Coccinellids are found worldwide, with over 5,000 species described,[4] more than 450 native to North America alone.

Coccinellidae are known colloquially as ladybirds (in Britain, Ireland, the Commonwealth, and the southern United States), ladybugs (originating in North America) or lady cows, among other names.[5] When they need to use a common name, entomologists widely prefer the names ladybird beetles or lady beetles[6] as these insects are not true bugs.

The Coccinellidae are generally considered useful insects, because many species feed on aphids or scale insects, which are pests in gardens, agricultural fields, orchards, and similar places. Within the colonies of such plant-eating pests, they will lay hundreds of eggs, and when these hatch the larvae will commence feeding immediately.[7] However, some species do have unwelcome effects. Among these, the most prominent are the subfamily Epilachninae, which are plant eaters. Usually, Epilachninae are only mild agricultural pests, eating the leaves of grain, potatoes, beans, and various other crops, but their numbers can increase explosively in years when their natural enemies are few, such as parasitoid wasps that attack their eggs. When that happens, they can do major crop damage. They occur in practically all the major crop-producing regions of temperate and tropical countries.

Etymology[edit]

Coccinelid is derived from the Latin word coccineus meaning "scarlet".[8] The name "ladybird" originated in Britain where the insects became known as 'Our Lady's bird or the Lady beetle.[9][10] Mary (Our Lady) was often depicted wearing a red cloak in early paintings, and the spots of the seven-spot ladybird (the most common in Europe) were said to symbolise her seven joys and seven sorrows.[9] In the United States, the name was adapted to "ladybug". Common names in other European languages have the same association, for example, the German name Marienkäfer translates to Marybeetle.[11]

Physical appearance[edit]

Most coccinellids have oval, dome-shaped bodies with six short legs. Depending on the species, they can have spots, stripes, or no markings at all. Seven-spotted coccinellids are red or orange with three spots on each side and one in the middle; they have a black head with white patches on each side.

As well as the usual yellow and scarlet colorings, many coccinellid species are mostly, or entirely, black, grey, or brown, and may be difficult for non-entomologists to recognise as coccinellids at all. Conversely, non-entomologists might easily mistake many other small beetles for coccinellids. For example, the tortoise beetles, like the ladybird beetles, look similar because they are shaped so that they can cling to a flat surface so closely that ants and many other enemies cannot grip them.

Non-entomologists are prone to misidentify a wide variety of beetle species in other families as "ladybirds", i.e. coccinellids. Beetles are particularly prone to such misidentification if they are spotted in red, orange or yellow and black. Examples include the much larger scarabaeid grapevine beetles and spotted species of the Chrysomelidae, Melyridae and others. Conversely, laymen may fail to identify unmarked species of Coccinellidae as "ladybirds". Other beetles that have a defensive hemispherical shape, like that of the Coccinellidae (for example the Cassidinae), also are often taken for ladybirds.

A common myth, totally unfounded, is that the number of spots on the insect's back indicates its age.[12][13] In fact, the underlying pattern and coloration are determined by the species and genetics of the beetle, and develop as the insect matures. In some species its appearance is fixed by the time it emerges from its pupa, though in most it may take some days for the colour of the adult beetle to mature and stabilise. Generally, the mature colour tends to be fuller and darker than the colour of the callow.

Biology[edit]

Basic anatomy of a ladybird

Coccinellids are best known as predators of Sternorrhyncha such as aphids and scale insects, but the range of prey species that various Coccinellidae may attack is much wider. A genus of small black ladybirds, Stethorus, presents one example of predation on non-Sternorrhyncha; they specialise in mites as prey, notably Tetranychus spider mites. Stethorus species accordingly are important in certain examples of biological control.[14]

Various larger species of Coccinellidae attack caterpillars and other beetle larvae.[14] Several genera feed on various insects or their eggs; for example, Coleomegilla species are significant predators of the eggs and larvae of moths such as species of Spodoptera and the Plutellidae.[15] Larvae and eggs of ladybirds, either their own or of other species, can also be important food resources when alternative prey are scarce. As a family, the Coccinellidae used to be regarded as purely carnivorous,[16] but they are now known to be far more omnivorous than previously thought, both as a family and in individual species; examination of gut contents of apparently specialist predators commonly yield residues of pollen and other plant materials. Besides the prey they favour, most predatory coccinellids include other items in their diets, including honeydew, pollen, plant sap, nectar, and various fungi. The significance of such nonprey items in their diets is still under investigation and discussion.[17]

Apart from the generalist aphid and scale predators and incidental substances of botanical origin, many Coccinellidae do favour or even specialise in certain prey types. This makes some of them particularly valuable as agents in biological control programmes. Determination of specialisation need not be a trivial matter, though; for example the larva of the Vedalia ladybird Rodolia cardinalis is a specialist predator on a few species of Monophlebidae, in particular Icerya purchasi, which is the most notorious of the cottony cushion scale species. However, the adult R. cardinalis can subsist for some months on a wider range of insects plus some nectar.[18]

Certain species of coccinellids are thought to lay extra infertile eggs with the fertile eggs, apparently to provide a backup food source for the larvae when they hatch. The ratio of infertile to fertile eggs increases with scarcity of food at the time of egg laying. Such a strategy amounts to the production of trophic eggs.[19]

Some species in the subfamily Epilachninae are herbivores, and can be very destructive agricultural pests (e.g., the Mexican bean beetle). Again, in the subfamily Coccinellinae, members of the tribe Halyziini and the genus Tythaspis are mycophagous.

While predatory species are often used as biological control agents, introduced species of coccinellids are not necessarily benign. Species such as Harmonia axyridis or Coccinella septempunctata in North America outcompete and displace native coccinellids and become pests themselves.[20]

The main predators of coccinellids are usually birds, but they are also the prey of frogs, wasps, spiders, and dragonflies. The bright colours of many coccinellids discourage some potential predators from making a meal of them. This phenomenon, called aposematism, works because predators learn by experience to associate certain prey phenotypes with a bad taste. A further defence, known as "reflex bleeding", exists in which an alkaloid toxin is exuded through the joints of the exoskeleton, triggered by mechanical stimulation (such as by predator attack) in both larval and adult beetles, deterring feeding.

Coccinellids in temperate regions enter diapause during the winter, so they often are among the first insects to appear in the spring. Some species (e.g., Hippodamia convergens) gather into groups and move to higher elevations, such as a mountain, to enter diapause. Most coccinellids overwinter as adults, aggregating on the south sides of large objects such as trees or houses during the winter months, dispersing in response to increasing day length in the spring.[21]

Predatory coccinellids are usually found on plants which harbour their prey. They lay their eggs near their prey, to increase the likelihood the larvae will find the prey easily. In Harmonia axyridis, eggs hatch in three to four days from clutches numbering from a few to several dozen. Depending on resource availability, the larvae pass through four instars over 10–14 days, after which pupation occurs. After a teneral period of several days, the adults become reproductively active and are able to reproduce again, although they may become reproductively quiescent if eclosing late in the season. Total life span is one to two years on average.

Infestations and impacts[edit]

In the United States, coccinellids usually begin to appear indoors in the autumn when they leave their summer feeding sites in fields, forests, and yards and search out places to spend the winter. Typically, when temperatures warm to the mid-60s F (around 18 °C) in the late afternoon, following a period of cooler weather, they will swarm onto or into buildings illuminated by the sun. Swarms of coccinellids fly to buildings in September through November depending on location and weather conditions. Homes or other buildings near fields or woods are particularly prone to infestation.[22]

After an abnormally long period of hot, dry weather in the summer of 1976 in the UK, a marked increase in the aphid population was followed by a "plague" of ladybirds, with many reports of people being bitten as the supply of aphids dwindled.[23][24] Recent studies suggest coccinellids can also cause allergic reactions, such as eye irritation or asthma.[25]

The presence of coccinellids in grape harvests can cause ladybird taint in wines produced from the grapes.[26]

As an alien species[edit]

Harmonia axyridis (the harlequin ladybird) is an example of how an animal might be partly welcome and partly harmful. It was introduced into North America from Asia in 1916 to control aphids, but is now the most common species, outcompeting many of the native species.[27] It has since spread to much of western Europe, reaching the UK in 2004.[27][28] It has become something of a domestic and agricultural pest in some regions, and gives cause for ecological concern. It similarly has turned up in parts of Africa, where it has proved variously unwelcome, perhaps most prominently in vine-related crops.

UK ladybird survey[edit]

Coccinella septempunctata pair mating. This seven-spotted species is by far the most common ladybird in Europe.

The atlas Ladybirds (Coccinellidae) of Britain and Ireland published in 2011[29] showed a decline of more than 20% in native species due to environmental changes and competition from foreign invaders. The distribution maps, compiled over a 20-year period with help from thousands of volunteers, showed a decline in the numbers of the common 10-spot and 14-spot ladybirds and a number of other species, including the 11-spot, 22-spot, cream-spot, water and hieroglyphic ladybirds, Coccidula rufa, Rhyzobius litura and Nephus redtenbacheri. Conversely, increases were seen in the numbers of harlequin, orange, pine, and 24-spot ladybirds, as well as Rhyzobius chrysomeloides. The kidney spot ladybird was recorded in Scotland for the first time in recent years, and the 13-spot was found to have recolonised Cornwall, Devon, and the New Forest. The most commonly recorded species was the 7-spot, closely followed by the Asian harlequin — an invader that arrived from continental Europe in 2003 after being introduced to control pests. An 'explosion' in the number of orange ladybirds, which feed on mildew, is thought to have been due to the warmer, damper conditions that now prevail in parts of England.[30]

Gallery[edit]

In popular culture[edit]

Ladybirds on Jurmala beach, Latvia

Coccinellids are, and have been for very many years, a favourite insect of children. The insects had many regional names (now mostly disused) in English, such as the lady-cows, may-bug, golden-knop, golden-bugs (Suffolk); and variations on Bishop-Barnaby (Norfolk dialect) – Barnabee, Burnabee, the Bishop-that-burneth, and bishy bishy barnabee.[31] The etymology is unclear, but it may be from St. Barnabas' feast in June, when the insect appears, or a corruption of "Bishop-that-burneth", from the fiery elytra of the beetles.[32]

The ladybird was immortalised in the popular children's nursery rhyme Ladybird, Ladybird:

Ladybird, ladybird, fly away home

Your house is on fire and your children are gone
All except one, and that's Little Anne

For she has crept under the warming pan.

This poem has its counterpart in German as Marienwürmchen, collected in Des Knaben Wunderhorn, and set to music by Robert Schumann as Op. 79, No. 13.

There is also a Polish nursery rhyme, "Little Ladybirds' Anthem", of which a part ("fly to the sky, little ladybird, bring me a piece of bread") became a saying:[33]

Mała Biedroneczka siedem kropek miała,

Na zielonej łące wesoło fruwała.
Złapał ją pajączek w swoją pajęczynę
- uratuję Cię Biedronko, a ty mi coś przynieś.

Biedroneczko leć do nieba, przynieś mi kawałek chleba.

Little ladybird had seven dots,

She was flying over a green meadow.
A little spider caught her in its spiderweb
I will set you free, little ladybird, and you bring me something.

Fly to the sky, little ladybird, bring me a piece of bread.

Many cultures consider coccinellids lucky and have nursery rhymes or local names for the insects that reflect this. For instance, the Turkish name for the insect is uğur böceği, literally meaning "good luck bug". In many countries, including Russia, Turkey, and Italy, the sight of a coccinellid is either a call to make a wish or a sign that a wish will soon be granted.

In Christian areas, coccinellids are often associated with the Virgin Mary and the name that the insect bears in the various languages of Europe corresponds to this. Though historically many European languages referenced Freyja, the fertility goddess of Norse mythology, in the names, the Virgin Mary has now largely supplanted her, so that, for example, freyjuhœna (Old Norse) and Frouehenge have been changed into marihøne (Norwegian) and Marienkäfer (German), which corresponds with Our Lady's bird.[34] Sometimes, the insect is referred to as belonging directly to God (Irish bóín Dé, Polish boża krówka, all meaning "God's [little] cow").[35] In Dutch it is called lieveheersbeestje, meaning "little animal of our Good Lord".

In both Hebrew and Yiddish, it is called "Moshe Rabbenu's (i.e. Moses's) little cow" or "little horse", apparently an adaptation from Slavic languages. Occasionally, it is called "little Messiah".[36]

Popular media[edit]

"Ladybugs" or "ladybirds" feature in a range of children's literature, as well as in art, TV, and film. They are often depicted in an anthropomorphic or otherwise fictionalised manner. In Roald Dahl's children's book James and the Giant Peach, The Ladybird (among a cast of anthropomorphic minibeast characters grown to human size) becomes perhaps the closest friend of the protagonist James, treating him with motherly affection. In the American-produced 1996 animated film version, she was voiced by Jane Leeves and renamed The Ladybug, despite Leeves' northern English interpretation.

In the animated film A Bug's Life, Francis the Ladybug (voiced by Denis Leary) is an aggressive coccinellid and the clown in P.T. Flea's circus. The contrast between his being a male and a "lady" bug is a recurring joke in the film.

Tree Fu Tom features ladybirds as "cows" being ranched by a southern-belle cowgirl.

Ledyba and Ledian of the Pokémon series are based on coccinellids.

Electro-Wave Human Tackle from the Japanese tokusatsu series Kamen Rider Stronger is a female superhero cyborg whose design is based on that of coccinellid.

Cartoon Hangover web-series Bravest Warriors features mascot character Catbug, a childlike anthropomorphic alien that appears to be a cross between a kitten and an adult coccinellid.

[edit]

Symbol of the Dutch Foundation Against Senseless Violence

Bold colours and simple shape have led to use as a logo for a wide range of organisations and companies, including:

In addition, it has been chosen as:

References[edit]

  1. ^ a b "Coccinellidae Latreille, 1807". Integrated Taxonomic Information System. Retrieved July 24, 2012. 
  2. ^ "Wikispecies: Microweiseinae". 2012. Retrieved 9 Mar 2013. 
  3. ^ Ainsley E. Seago, Jose Adriano Giorgi, Jiahui Li, Adam Ślipiński, Phylogeny, classification and evolution of ladybird beetles (Coleoptera: Coccinellidae) based on simultaneous analysis of molecular and morphological data, Molecular Phylogenetics and Evolution, Volume 60, Issue 1, July 2011, Pages 137-151, ISSN 1055-7903, http://dx.doi.org/10.1016/j.ympev.2011.03.015. (http://www.sciencedirect.com/science/article/pii/S1055790311001540)
  4. ^ Judy Allen & Tudor Humphries (2000). Are You A Ladybug?, Kingfisher, p. 30
  5. ^ Definition of lady cow, Webster's Revised Unabridged Dictionary (1913), provided by die.net. Retrieved 14 November 2008.
  6. ^ White, R.E. 1983. A field guide to the beetles of North America. Peterson Field Guide Series #29.
  7. ^ http://animals.nationalgeographic.com/animals/bugs/ladybug/?source=A-to-Z
  8. ^ Brown, L., ed. (2007). The Shorter Oxford English Dictionary 1 (6 ed.). p. 441. 
  9. ^ a b Anonymous. "Why are ladybirds so-called?". UK Ladybird survey. Retrieved 15 October 2010. 
  10. ^ Samaha, John M. "Marian Roots of the Name". Our Lady's Bug. Dayton, Ohio: International Marian Research Institute. Retrieved 15 October 2010. 
  11. ^ Anonymous. "common name: ladybirds, ladybird beetles, lady beetles, ladybugs (of Florida)". Featured creatures. University of Florida. Retrieved 8 April 2010. 
  12. ^ "Everything Ladybug! The source for Ladybug Stuff!". Everything-ladybug.com. Retrieved 22 June 2010. 
  13. ^ Anonymous. "Ladybird spotters". UK Ladybird survey. Retrieved 17 June 2010. 
  14. ^ a b Hodek, Ivo; Honek, A. ; van Emden, Helmut F. Ecology and Behaviour of the Ladybird Beetles. Publisher: Wiley-Blackwell 2012. ISBN 978-1405184229
  15. ^ Roger, Caroline. Mechanisms of Prey Selection in the Ladybeetle Coleomegilla Maculata. Thesis. Department of Natural Resource Sciences. Macdonald campus of McGill University Montréal. Canada 1999 0-612-50249-X
  16. ^ Smart, John (1963). British Museum (Natural History) Instructions for Collectors NO. 4A. Insects. London: Trustees of the British Museum. 
  17. ^ Almeida, Lúcia M. ; Corrêa, Geovan H. Giorgi, José A. ; Grossi, Paschoal C. New record of predatory ladybird beetle (Coleoptera, Coccinellidae) feeding on extrafloral nectaries. Revista Brasileira de Entomologia 55(3): 447–450, setembro, 2011
  18. ^ Sands, D. P. A. and R. G. Van Driesche. 2000. Evaluating host specificity of agents for biological control of arthropods: rationale, methodology and interpretation, pp. 69-83. In Van Driesche, R. G., T. A. Heard, A. S. McClay, and R. Reardon (eds.). Proceedings of Session: Host Specificity Testing of Exotic Arthropod Biological Control Agents: The Biological Basis for Improvement in Safety. Xth International Symposium on Biological Control of Weeds. July 4–14, 1999. Bozeman, Montana. U.S.D.A. Forest Service Bulletin FHTET-99-1, Morgantown, West Virginia, U.S.A.
  19. ^ J. Perry & B. Roitberg (2005). "Ladybird mothers mitigate offspring starvation risk by laying trophic eggs". Behavioral Ecology and Sociobiology 58 (6): 578–586. doi:10.1007/s00265-005-0947-1. 
  20. ^ http://www.treknature.com/gallery/photo268028.htm
  21. ^ A. Honek, Z. Martinkova & S. Pekar (2007). "Aggregation characteristics of three species of Coccinellidae (Coleoptera) at hibernation sites". European Journal of Entomology 104 (1): 51–56. 
  22. ^ University of Kentucky-College of Agriculture Cooperative Extension Service
  23. ^ Anonymous (5 July 2001). "Phew, what a scorcher!". The Northern Echo. Retrieved 8 April 2010. [dead link]
  24. ^ Wainwright, Martin (17 May 2006). "The great drought". London: The Guardian. Retrieved 8 April 2010. 
  25. ^ DMinSite, a division of Lagniappe Marketing. "Do Ladybugs BITE? And How Can You Keep Them Out of the House?". Gardensalive.com. Retrieved 2010-06-22. 
  26. ^ Easton, Sally (2 February 2012). "Ladybird contamination on the rise". The Drinks Business. Union Press Ltd. Retrieved 21 June 2013. 
  27. ^ a b Anonymous (5 October 2004). "'Deadly ladybird' sighted in UK". BBC News. Retrieved 17 June 2010. 
  28. ^ Anonymous. "The Harlequin Ladybird has landed!". The Harlequin ladybird survey. Retrieved 17 June 2010. 
  29. ^ Roy, Helen; Peter Brown, Robert Frost, Remy Poland (15 June 2011). Ladybirds (Coccinellidae) of Britain and Ireland. The Field Studies Council. p. 204. ISBN 978-1-906698-20-1. 
  30. ^ Sample, Ian (15 June 2011). "Spot check finds Britain's native ladybirds struggling to compete with alien invaders". The Guardian (Guardian Newspapers ltd.). p. 3. Retrieved 17 June 2011. 
  31. ^ Timmins, Nicholas (14 October 1994). "The Tories in Bournemouth: Teachers promised support as Shephard calls truce". The Independent (London). 
  32. ^ Lewie C. Roache (1960) Ladybug, Ladybug: What's in a Name? The Coleopterists Bulletin 14(1):21-25.
  33. ^ http://ppmalomice.szkolnastrona.pl/index.php?p=m&idg=zt,50,90
  34. ^ "Bishop Barnaby". Notes and Queries 9. 1849-12-29. 
  35. ^ [1][dead link]
  36. ^ Born to Kvetch, Michael Wex, St. Martin's Press, New York, 2005, ISBN 0-312-30741-1.
  37. ^ Anonymous (April 2004). "Speech by Mrs Maud de Boer-Buquicchio on the occasion of the placement of a ladybird tile at the Council of Europe". Council of Europe. Retrieved 21 September 2011. 
  38. ^ ASA.osdcms.com
  39. ^ http://www.candanchu.com

External links[edit]