Coccinellidae

Coccinellidae is a family of beetles, known variously as ladybirds (UK, Ireland, Australia, Pakistan, South Africa, New Zealand, India, Malta, parts of Canada), or ladybugs (North America). Scientists increasingly prefer the names ladybird beetles or lady beetles, as these insects are neither birds nor bugs. Lesser-used names include ladyclock, lady cow, and lady fly.^[1]

Coccinellids are small insects, ranging from 1 mm to 10 mm (0.04 to 0.4 inches), and are commonly yellow, orange, or scarlet with small black spots on their wing covers, with black legs, head and antennae. A very large number of coccinellid species are mostly, or entirely, black, grey, or brown and may be difficult for non-entomologists to recognize as coccinellids. Conversely, there are many small beetles that are easily mistaken for coccinellids, such as the tortoise beetles.

Coccinellids are found worldwide, with over 5,000 species described,^[2] more than 450 native to North America alone.

A few species are considered pests in North America and Europe, but they are generally considered useful insects as many species feed on aphids or scale insects, which are pests in gardens, agricultural fields, orchards, and similar places. Harmonia axyridis (or the Harlequin ladybug) was introduced into North America from Asia in 1988 to control aphids but is now the most common species as it is out-competing many of the native species.^[3] It has since spread to much of western Europe, reaching the UK in 2004.^[3][4]

A common myth is that the number of spots on the insect's back indicates its age.^[5][6]

Contents 1 Etymology 2 Biology 3 Habitats 4 Coccinellids as household pests 4.1 Infestations 4.2 Human impact 5 In popular culture 5.1 As a logo 6 References 7 External links

Etymology

The name "ladybird" originated in the Middle Ages when the insects were known as the "beetle of Our Lady" . They were named after The Virgin Mary, who in early religious paintings was often shown wearing a red cloak. The spots of the seven spot ladybird were said to symbolise seven joys and seven sorrows.^[7] Common names in other European languages have the same association (the German name Marienkäfer translates to "Marybeetle" or, literally, Mary-chafer).^[8] In the United States the name was Americanized to "ladybug".^[8]

Biology

Coccinellids are typically predators of Hemiptera such as aphids and scale insects, though conspecific larvae and eggs can also be important resources when alternative prey are scarce. Members of the subfamily Epilachninae are herbivores, and can be very destructive agricultural pests (e.g., the Mexican bean beetle). While predatory species are often used as biological control agents, introduced species of ladybirds (such as Harmonia axyridis or Coccinella septempunctata in North America) outcompete and displace native coccinellids and become pests in their own right.

Coccinellids are often brightly colored to ward away potential predators. This phenomenon is called aposematism and works because predators learn by experience to associate certain prey phenotypes with a bad taste (or worse). Mechanical stimulation (such as by predator attack) causes "reflex bleeding" in both larval and adult ladybird beetles, in which an alkaloid toxin is exuded through the joints of the exoskeleton, deterring feeding. Ladybugs, as well as other Coccinellids are known to spray a toxin that is venomous to certain mammals and other insects when threatened.

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.^[9] In Harmonia axyridis, eggs hatch in 3–4 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 1–2 years on average.

It is thought that certain species of Coccinellids lay extra infertile eggs with the fertile eggs. These appear 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.^[10]

Habitats

Most coccinellids are beneficial to gardeners in general, as they feed on aphids, scale insects, mealybugs, and mites throughout the winter. As in many insects, ladybugs 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 land, such as a mountain, to enter diapause. Predatory ladybugs are usually found on plants where aphids or scale insects are, and they lay their eggs near their prey, to increase the likelihood the larvae will find the prey easily. Ladybugs are cosmopolitan in distribution, as are their prey.

Ladybugs also require a source of pollen for food and are attracted to specific types of plants. The most popular ones are any type of mustard plant, as well as other early blooming nectar and pollen sources, like buckwheat, coriander, red or crimson clover, and legumes like vetches, and also early aphid sources, such as bronze fennel, dill, coriander, caraway, angelica, tansy, yarrow, of the wild carrot family, Apiaceae. Other plants that also attract ladybugs include coreopsis, cosmos (especially the white ones), dandelions and scented geraniums.

Ladybugs are sensitive to most synthetic insecticides. If food sources are limited, oviposition is reduced. A larva uses its sharp jaws to crush an aphid's body and sucks out the aphid's juices.

Coccinellids as household pests

Infestations

In the United States, ladybugs usually begin to appear indoors in the fall. They leave their summer feeding sites in fields, forests and yards looking for a place to spend the winter. Typically when temperatures warm to the mid 60s Fahrenheit in the late afternoon, following a period of cooler weather, they will swarm onto or into buildings illuminated by the sun. Swarms of ladybugs fly to buildings in September through November depending on location and weather conditions. Also, homes or buildings near fields or woods are more prone to infestation.^[11]

The presence of ladybugs in grape harvests can cause ladybird taint in wines produced from the grapes.

Human impact

After an abnormally long period of hot dry weather in the Summer of 1976 in the UK, there was a marked increase in the aphid population followed by a "plague" of ladybirds, with many reports of people being bitten as the supply of aphids dwindled.^[12][13] Recent studies suggest that coccinelidae can also cause allergic reactions, such as eye irritation or asthma.^[14]

In popular culture

Coccinellids are and have been for very many years a favorite insects of children. The insects had many regional names (now mostly disused) such as the lady-cows, may-bug, golden-knop, golden-bugs (Suffolk); and variations on Bishop-Barnaby (Norfolk dialect) – Barnabee, Burnabee, and the Bishop-that-burneth. 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.^[15]

The ladybird was immortalised in the still-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.

In parts of Northern Europe, tradition says that a persons wish is granted if a ladybird lands on them (this tradition lives on in North America, where children capture a ladybug, make a wish, and then "blow it away" back home to make the wish come true). In Italy, it is said by some that if a ladybird flies into a bedroom, it is considered good luck. In central Europe, a ladybird crawling across a girl's hand is thought to mean she will get married within the year. In some cultures they are referred to as fortune bugs.

In Russia, a popular children's rhyme exists with a call to fly to the sky and bring back bread; similarly, in Denmark a ladybird, called a mariehøne ("Mary's hen"), is asked by children to fly to 'our lord in heaven and ask for fairer weather in the morning'.

The name that the insect bears in the various languages of Europe is mythic. In this, as in other cases, the Virgin Mary has supplanted Freyja, the fertility goddess of Norse mythology; so that freyjuhœna (Old Norse) and Frouehenge have been changed into marihøne (Norwegian) and Marienvoglein (German), which corresponds with Our Lady's Bird; similarly, in Serbian the common name is bubamara (buba-Mara, Mary-beetle). In Spanish its most common name is mariquita, also a reference to the Virgin Mary. The esteem with which these insects are regarded has roots in ancient beliefs.^[16]

In Irish, the insect is called bóín Dé — or "God's little cow" and in Welsh, the term buwch goch gota is used, containing the word 'buwch' meaning "cow"; similarly, in Croatian it is called Božja ovčica ("God's little sheep") and in Romanian gărgăriţă, buburuză, vaca-Domnului ("Lord's cow"), boul Domnului ("Lord's oxen") or găina lui Dumnezeu ("God's hen").^[17] Moreover, in Romanian it is also called mărie, măriuţă or mămăruţă, terms derived from the personal name Mary^[17] (cf. the Norwegian, German and Serbian names for the ladybug).

In France it is known as bête à bon Dieu, "the Good Lord's animal",^[18] and in Russia, Божья коровка ("God's little cow"),^[18] while in both Hebrew and Yiddish, it is called "Moshe Rabbenu's (i.e. Moses's) little cow" or "Moshe Rabbenu's little horse", apparently an adaptation of the Russian name, or sometimes "Little Messiah".^[18]
They are also considered to be bringers of good weather.

In Iran, two Persian words are used; ﮐﻔﺶ ﺪوزک and ﭘﻴﻨﻪ ﺪﻮﺰ, both meaning "shoe cobbler".

In Greece, ladybirds are called πασχαλίτσα (paschalitsa), because they are found abundantly in Eastertime, along with paschalia, the Common Lilac plant, which flowers at the same time.

In Malta, the ladybird is called nannakola, and little children sing: Nannakola, mur l-iskola/Aqbad siġġu u ibda ogħla (Ladybird go to school, get a chair and start jumping).

In Turkey, ladybirds are called uğur böceği, literally meaning luck bug. When a ladybird lands on children, they wish something and sing Uç uç böceğim, annen sana terlik pabuç alacak (Fly fly my bug, your mother will buy you slippers and shoes).

In Finnish, ladybird is, for its blood red color, called leppäkerttu, translating to Blood Gertrud from the ancient Baltic-Finnic meaning blood or the word leppä (that means alder in modern Finnish).^[19] An alternative name is leppäpirkko. These differ by the female name at the end.

In Indonesia it is called a Kumbang Koksi, and is a symbol of good luck to those who see it.

In Dutch, the ladybird is called lieveheersbeestje, translating to Our Dear Lord's little creature. It is also common to ask ladybugs to bring fair weather the next morning by saying "morgen mooi weer" upon encountering them.

In Bulgarian, it is also called "bozha kravichka" (God's little cow) or, "kalinka" on the account of its red colour.

In Poland it is called biedronka as well as 'boża krówka' ('krówka' being the diminutive of krowa — cow).

In Russia it is also known as 'bożja korowka'.

In Argentina it is called "Vaquita de San Antonio" (San Antonio's little cow) and it is considered to bring good luck.

In Portugal it is called "Joaninha" (little Joana) and children sing "Joaninha, voa, voa que o teu pai está em Lisboa..." (Ladybug fly away cause your father is in Lisbon) followed by one of several different rhymes.

As a logo

Bold colors and simple shape—and its non-threatening nature—have led to use as a logo for a wide range of organizations and companies including these:

• Symbol of the Dutch Foundation Against Senseless Violence^[20]
• Ladybird Books (owned by Pearson PLC)
• Ladybird range of children's clothing sold by Woolworths.co.uk and formerly by the (now defunct) Woolworth's chain store in the UK
• Polish supermarket chain Biedronka
• Estonian mobile operator EMT^[21]
• Software development firm Axosoft.
• Symbol of the Finnish Swedish People's Party.

In addition, it has been chosen as

• State insect of: Delaware, Massachusetts, New Hampshire, New York, Ohio, and Tennessee, though only New York has selected a species native to the United States (Coccinella novemnotata); the other states have all adopted an invasive European species (Coccinella septempunctata).
• An "official national mascot"^[22] for Alpha Sigma Alpha, a national sorority in the United States

References

Notes

External links

• Ladybirds of Australia
• Harlequin Ladybird survey in the British Isles
• Biological control: Predators: Lady beetles Cornell University's Guide to natural enemies in North America
• Lady Beetles of Florida on the UF / IFAS Featured Creatures Web site
• Taiwanese site Images