dcsimg

Biology

provided by Arkive
In the common blue, the number of generations produced each year varies depending on the geographic location of the population. In the majority of England and Wales there are two broods per year (the populations are 'bivoltine'), with adults on the wing in May and June and again in August and September. Populations in Scotland and parts of England to the north of Yorkshire are single-brooded ('univoltine'); adults are present between June and September, with emergence occurring earlier in warmer areas. Occasionally, in warm years, double-brooded and single-brooded populations may go on to produce an extra brood in the same year, thanks to the warm weather. This phenomenon indicates that the factors governing the number of broods produced are environmental, rather than genetic (4). The eggs are laid singly on the foodplants and take around a week to hatch (3). Caterpillars of the first generation (or of the only generation in single-brooded populations) take around 6 weeks to become fully developed. Second brood caterpillars overwinter when partly grown, and complete their development during the following year (3). Pupation occurs either at the base of the foodplant or amongst litter on the ground (4) and adult butterflies emerge after around two weeks (3). In common with many other species of blue butterflies, the caterpillars of the common blue are attractive to ants when they are fully grown. The pupae are also attractive to ants and are often carried away into ant nests (4).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Conservation

provided by Arkive
Not relevant.
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Description

provided by Arkive
The common blue is the most widespread of the blue butterflies in Britain (4), and as the name suggests, it is one of the most common butterflies in Europe (5). The males are a striking bluish-violet colour, but females are brown with orange spots near the margins of the wings. In both sexes, the undersides of the wings are greyish brown with blackish spots and orange crescents towards the margins of the wings (2). The caterpillar has a stout body, which tapers towards the tips. The head is black and the body is green. A darker green line bordered with white passes along the centre of the back. There is also a whitish-green line along the sides (3).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Habitat

provided by Arkive
Occurs in a wide range of grassy habitats where the foodplants occur. The main foodplant is common bird's foot trefoil (Lotus corniculatus), although other trefoils, clovers (Trifolium) and related plants may be used (2) (5). This species tends to be found in sunny, sheltered areas, and typical habitats include downland, woodland clearings, coastal dunes, road verges, golf courses, cemeteries and occasionally gardens (4) (5).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Range

provided by Arkive
This butterfly is found throughout Britain and occurs on most off-shore islands including the Outer Hebrides and Orkney (4). It is most numerous in the south of England and Wales and is scarce in areas at altitudes of over 300 meters, becoming absent over 500 m (4). Elsewhere, the range of this species extends throughout Europe, North Africa and in temperate parts of Asia (2).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Status

provided by Arkive
Not threatened (4).
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Threats

provided by Arkive
This species is not threatened at present.
license
cc-by-nc-sa-3.0
copyright
Wildscreen
original
visit source
partner site
Arkive

Associations

provided by BioImages, the virtual fieldguide, UK
Animal / parasitoid / endoparasitoid
larva of Aplomya confinis is endoparasitoid of larva of Polyommatus icarus

license
cc-by-nc-sa-3.0
copyright
BioImages
project
BioImages

Brief Summary

provided by Papillons de Jardin
L'Argus bleu (ou Azuré commun) est le plus répandu d'une famille très nombreuse au sein de laquelle il est souvent difficile de distinguer les espèces ! Il est présent de l'Afrique du nord à l'Asie en passant par l'Europe. Mâles et femelles papillonnent dans les prairies et on les voit facilement en tandem tête-bêche : ils s'accouplent et butinent en même temps... Observation en vol : Avril à octobre. Nombre de générations par an : Jusqu'à 3. Milieux de vie : Prairies et lieux enherbés, y compris les friches, parcs et jardins des abords de villes. Description Adulte Envergure : 30-35 mm. Apparence : Le mâle et la femelle sont très différents. Le mâle est bleu sombre, de manière uniforme, avec juste le bord supérieur des ailes bordé de blanc. Par contre, la femelle est uniformément brune, avec des reflets bleus (plus ou moins étendus) à la base des ailes et des taches orangées sur le pourtour. Le dessous des ailes est presque identique chez les deux sexes : gris brun avec des reflets bleus à la base des ailes arrière. On peut observer une série de taches orangées en forme de croissant, et un point noir bien marqué.
license
cc-by-nc-sa-3.0
copyright
Noé Conservation
partner site
Papillons de Jardin

Life Cycle

provided by Papillons de Jardin
L'oeuf est blanchâtre, hémisphérique. Les oeufs sont déposés un à un (quelques fois par 2 ou 3) sur les fleurs de la plante hôte. Chenille Taille : 10-15 mm au dernier stade. Apparence : La larve a un peu une forme de cloporte, vert pomme avec des poils fins et une fine ligne jaune de chaque côté. Plantes hôtes : Légumineuses diverses (trèfles, luzernes, bugranes, genêts, etc.). Chrysalide: Elle mesure environ 10 mm, est lisse, luisante, brune verdâtre et sans ornementation. Elle est bombée au niveau de l'abdomen. Elle est libre et se trouve au sol, avec les débris végétaux.
license
cc-by-nc-sa-3.0
copyright
Noé Conservation
partner site
Papillons de Jardin

Common blue

provided by wikipedia EN

The common blue butterfly or European common blue[2] (Polyommatus icarus) is a butterfly in the family Lycaenidae and subfamily Polyommatinae. The butterfly is found throughout the Palearctic. Butterflies in the Polyommatinae are collectively called blues, from the coloring of the wings. Common blue males usually have wings that are blue above with a black-brown border and a white fringe. The females are usually brown above with a blue dusting and orange spots.[3]

Mating in Buckinghamshire
male left; female right

The Common blue was elected as the national butterfly of Israel in 2023.[4]

Taxonomy and phylogeny

This species was first described by Siegmund Adrian von Rottemburg in 1775. Vernacular names that have been given to P. icarus include little blew argus, blew argus, mixed argus, selvedg’d argus, ultramarine blue, caerulean butterfly, and alexis.

Subspecies

Subspecies include:[5]

  • P. i. icarus (Europe, Caucasus, Transcaucasia)
  • P. i. mariscolore (Kane, 1893) (Ireland)
  • P. i. fuchsi (Sheljuzhko, 1928) (South Siberia, Transbaikalia)
  • P. i. omelkoi Dubatolov & Korshunov, 1995 (Amur, Ussuri)
  • P. i. ammosovi (Kurenzov, 1970) (Central Yakutia, Far East, Kamchatka)
  • P. i. fugitiva (Butler, 1881) (Pakistan)
  • P. i. napaea (Grum-Grshimailo, 1891) (Tian-Shan)
  • P. i. zelleri Verity, 1919

Description

Polyommatus icarus has a wingspan of 28–36 millimetres (1.1–1.4 in).[6] The dorsal side of the wings is an iridescent lilac blue, bright violet-blue, or almost hyacinth-blue with a thin black border. Females' wings are brown or black-brown with a row of red reddish yellow spots along the edges of the wings (marginal spots) and usually some blue at the base. The extent of blue and brown is extremely variable depending on location.[3] The top of the wings in the female may be mostly blue, especially in Ireland and Scotland, but it always has red spots. The ventral side has a greyish or dust-grey base colour in the males and a more brownish hue in the females.[3] Both sexes have a row of red or orange spots along the edge of the hindwing and extending onto the forewing, though they are generally fainter there, particularly in the males, where they are sometimes missing altogether. There are about a dozen black-centered white spots (ocelli) on the hindwing and nine on the forewing. These usually include one in the middle of the forewing cell, absent in Chapman's and Escher's blues. The fringes on the outer edge of the wings are uniform white, not crossed with black lines as in the chalkhill and Adonis blues (that is, the common blue lacks checkering).[3]

Other similar species are:-

Figs Figs 2, 2a, 2b larva after last moult 2c pupa

The caterpillar is small, pale green with yellow stripes and, as usual with Lycaenid larvae, rather slug-like.[7]

Geographic range

Underside

The common blue butterfly is found in Europe, North Africa, the Canary Islands, and east across the Palearctic to Northern China. Recently it was discovered in Quebec, Canada. It is widespread in the British Isles. Its distribution trend shows a 15% decline since the 1970s.[8]

U.K. and Ireland

The common blue is Britain and Ireland's (and probably Europe's) most common and most widespread blue. It is found as far north as Orkney and on most of the Outer Hebrides. A range of grassland habitats are used: meadows, coastal dunes, woodland clearings, and also many man-made habitats, anywhere their food plants are found.[8]

North America

This is a recently introduced species in eastern Canada.[9][10] It was discovered in Mirabel, Quebec, Canada, by Ara Sarafian, an amateur entomologist who observed the butterfly from 2005 to 2008. He contacted the Canadian National Collection of Insects in Ottawa where the butterfly was identified as Polyommatus icarus, a newly introduced butterfly to Canada and to North America. The butterfly seems to be well established and is extending its range from year to year.[11][12] A study from Montreal, Quebec, Canada showed that the common blue is most abundant in areas with greater urban land cover and where their preferred larval host plant, bird's foot trefoil (Lotus corniculatus), can be found.[13]

Habitat

These butterflies inhabit flowery or grassy places, warm and cool, open or wooded areas and at all altitudes up to high alpine meadows at an elevation of 0–2,700 m (0–9,000 ft) above sea level.[6][3] It mostly resides on chalk or limestone grassland, but also in smaller numbers in woodland clearings, meadows, heathlands, sand dunes, along railway embankments, and under cliffs.[8]

Source of decline

Previously, P. icarus was a very common species that occupied Europe and Asia, and was one of the most widely distributed butterflies in Britain. It is known to be tolerant of many habitats, including a wide range of grasslands. There has been an estimated 74% loss of the butterfly population since 1901. This could be due to the fact that 46% of the total land area covered by the butterfly's preferred host plant, Lotus corniculatus, has also been lost since 1901.[8] This host plant is a favored plant for two reasons: it provides adult nutrition, as well as food for the larva after it hatches.[14]

Food resources

Larval food plants

The larvae feed on plants from the bean family, Leguminosae. Recorded food plants are Lathyrus species, Vicia species, Vicia cracca, Oxytropis campestris, bird's foot trefoil (Lotus corniculatus), Oxytropis pyrenaica, Astragalus aristatus, Astragalus onobrychis, Astragalus pinetorum, black medick (Medicago lupulina), Medicago romanica, Medicago falcata, common restharrow (Ononis repens), wild thyme Thymus serpyllum, lesser trefoil (Trifolium dubium), Trifolium pratense and white clover (Trifolium repens).[5][15]

Flavonoids

Common blues sequester flavonoids from their host plants and allocate these pigments that are UV-absorbing into their wings. These flavonoid pigments in females attract males. Males who patrol areas of suitable habitats while searching for virgin females stop and inspect females who have flavonoid pigments in them. This may be due to the fact that flavonoid pigments that have UV absorption increase color saturation on females and allow females to be more conspicuous.[16] There are also some other advantages of sequestering flavonoids, including the protection of eggs from adverse UV chemical reactions, as the butterflies will absorb the UV rays, and the flavonoids can offer a chemical defense against predators or pathogens.

Flavonoid sequestration is much more effective when coming from natural host plants than from experimentally offered diets. Females sequester about 60% more flavonoids than do males. This richness in females may increase visibility, but could also confer information about feeding history, and consequentially the quality of potential mate.[17] Flavonoid sequestration is an important component of intraspecific visual communication and sexual signaling in Polyommatus butterflies.

Parental care

Oviposition

During oviposition, females must locate a potential host plant and evaluate its suitability as the host plant for oviposition. P. icarus uses visual cues to conduct this task. Females use several plants in the family Fabaceae as larval host plants, many which could also potentially function as nectar sources. P. icarus prefers plants with flowers over plants without, and prefers to oviposit near the flowers.[14]

Life cycle

As a caterpillar, the common blue eats leaves. As an adult butterfly, it feeds on wildflower nectar and excrement. The adult lives 3 weeks.

Males are often very obvious as they defend territories against rivals and seek out the more reclusive females. In the south of Britain there are two broods a year, flying in May and June and again in August and September.[6] Northern England has one brood, flying between June and September. In a year with a long warm season, there is sometimes a partial third brood in the south flying into October.

Eggs

The egg stage lasts for around eight days. The eggs are white and shaped like flattened spheres. The eggs are very small, about 0.60 millimetres (132 in).[18] The ground color of the egg sac is pale-greenish grey, with the actual arrangement being white. Eggs are laid singly on young shoots of the food plant.

Larvae

The larvae emerge around a week or two after eggs are laid. The larvae of P. icarus feed on the underside of leaves, causing blotching. Hibernation occurs as a half-grown larvae.[19] They are attractive to ants of genera Myrmica, Lasius, Formica, Plagiolepiss[15], but not as much as some other species of blues. The chrysalis is olive green/brown and formed on the ground, where it is attended by ants of genera Myrmica, Lasius, Formica, Plagiolepiss, [15] which will often take it into their nests. The larva creates a substance called honeydew, which the ants eat while the butterfly lives in the ant hill. The relationship between these ants and blue common larvae is described to be facultatively mutualistic.[20][19]

Instars of larvae

There are five instars of larvae. During the first instar, larva emerge and eat away the crown of the egg. The segments of the larvae are large and rounded, and the following segments are smaller. The body is a light green, and is whitish in light. This stage lasts about nine days.[18] The second instar, after the first moult, adds a couple of body segments onto the larvae, and the body is more green. The third instar signifies more feeding and growing in size of the larvae. They are about 3.2 millimetres (0.13 in) long and the head and legs are black colored. In the fourth and fifth instar, the larvae becomes very green, has ten body segments, and measures about 13 millimetres (0.51 in) in length.

External effects on larval growth and development

Larval growth rates are thought to be determined mainly by temperature and food quality and availability. The larvae of P. icarus are oligophagous, meaning they utilize a range of host plants in the family fabaceae, as well as have a mutualistic relationship with ants. For both male and female larvae, the total development time is longer with longer day lengths, corresponding to earlier times in the season. When larvae are born earlier in the season, they take a longer time to develop. When they are born later, they take a shorter time to develop. Thus the external effect of photoperiod affects the length of development for the larvae.[19]

Pupae

Pupation, a stage that lasts about two weeks, occurs under silk strands at the base of the food plant. The chrysalis is olive green/brown and formed on the ground, where it is attended by ants. Ants may aid in protecting the pupa and may bury it to protect it from predators.

Adults

The male, with a bluer color, is more conspicuous than the female, which has brown upperwings. Males fly farther distances in search of territories that have fertile females. Females fly lower and search for nectar and places to lay her eggs. Wing span ranges from 29–36 millimetres (1.1–1.4 in). When the sexes meet, copulation occurs immediately, usually without any courtship ritual.

Physiology

Vision

Visual systems in butterflies are highly diverse and their color vision abilities have only begun to be explored. To see color, P. icarus uses a duplicated blue opsin in conjunction with its long-wavelength opsin LWRh. This enables the common blue to see color in the green part of the light spectrum extending up to 560 nm (2.2×10−5 in). There is also a difference between the dorsal and ventral eye-shine of P. icarus, with the dorsal retina dominated by yellow-reflecting ommatidia and the ventral exhibiting yellow and red-reflecting ommatidia. P. icarus is able to use color vision and distinguish between yellow of 590 nm (2.3×10−5 in) and blue of 430 nm (1.7×10−5 in), but is not able to distinguish between yellow and red of 640 nm.[21]

Etymology

Named in the Classical tradition. In Greek mythology, Icarus was the son of the master craftsman Daedalus, the architect of the labyrinth of Crete.

See also

References

  1. ^ "Polyommatus icarus". IUCN Red List of Threatened Species.
  2. ^ "European Common Blue". Butterflies and Moths of North America. Metalmark Web and Data. Retrieved 13 January 2022.
  3. ^ a b c d e Rowlings, Matt. Euro Butterflies
  4. ^ ויינשטיין, זיו (23 April 2023). "כחליל השברק נבחר לפרפר הלאומי של ישראל - וואלה! תיירות". וואלה! (in Hebrew). Retrieved 23 April 2023.
  5. ^ a b Funet
  6. ^ a b c Simon Coombes Captain's European Butterfly Guide
  7. ^ Kimmo Silvonen Larvae of North-European Lepidoptera
  8. ^ a b c d Leon-Cortes, Jorge (1999). "Detecting decline in a formerly widespread species: how common is the common blue butterfly Polyommatus icarus?". Ecography. 22 (6): 643–650. doi:10.1111/j.1600-0587.1999.tb00513.x.
  9. ^ Butterflies and Moths of North America
  10. ^ Butterflies of America
  11. ^ Rivest, Stephanie A.; Kharouba, Heather M. (2021-07-19). "Anthropogenic disturbance promotes the abundance of a newly introduced butterfly, the European common blue (Polyommatus icarus; Lepidoptera: Lycaenidae), in Canada". Canadian Journal of Zoology. doi:10.1139/cjz-2021-0009.
  12. ^ Focusing on Wildlife
  13. ^ Rivest, Stephanie A.; Kharouba, Heather M. (2021-07-19). "Anthropogenic disturbance promotes the abundance of a newly introduced butterfly, the European common blue (Polyommatus icarus; Lepidoptera: Lycaenidae), in Canada". Canadian Journal of Zoology. doi:10.1139/cjz-2021-0009.
  14. ^ a b Janz, Niklas (1999). "The role of Nectar sources for oviposition decisions of the Common Blue Butterfly Polyommatus icarus". Oikos. 109 (3): 535–538. doi:10.1111/j.0030-1299.2005.13817.x.
  15. ^ a b c Paolo Mazzei, Daniel Morel, Raniero Panfili Moths and Butterflies of Europe and North Africa Archived 2018-03-24 at the Wayback Machine
  16. ^ Burghardt, Frank (2000). "Flavonoid sequestration by the common blue butterfly Polyommatus icarus: quantitative intraspecific variation in relation to larval hostplant, sex and body size". Biochemical Systematics and Ecology. 29 (9): 875–889. doi:10.1016/s0305-1978(01)00036-9. PMID 11445289.
  17. ^ Burghardt, Frank (2000). "Flavonoid wing pigments increase attractiveness of female common blue ( Polyommatus icarus ) butterflies to mate-Searching males" (PDF). Naturwissenschaften. 87 (7): 304–307. Bibcode:2000NW.....87..304B. doi:10.1007/s001140050726. PMID 11013877. S2CID 14590090.
  18. ^ a b Frohawk, Frederick William (1914). Natural History of British Butterflies. London: Hutchinson (published 1924).
  19. ^ a b c Leimar, Olaf (1996). "Life History Plasticity: Influence of Photoperiod on Growth and Development in the Common Blue Butterfly". Oikos. 76 (2): 228–234. CiteSeerX 10.1.1.560.4212. doi:10.2307/3546194. JSTOR 3546194.
  20. ^ Fiedler, Konrad; Hölldobler, Bert (1992-10-01). "Ants and Polyommatus icarus immatures (Lycaenidae) —sex-related developmental benefits and costs of ant attendance". Oecologia. 91 (4): 468–473. Bibcode:1992Oecol..91..468F. doi:10.1007/BF00650318. ISSN 0029-8549. PMID 28313497. S2CID 23701682.
  21. ^ Sison-Mangus, Marilou (November 2007). "The lycaenid butterlfy Polyommatus icarus uses a duplicated blue opsin to see green". Journal of Experimental Biology: 361–369.

license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN

Common blue: Brief Summary

provided by wikipedia EN

The common blue butterfly or European common blue (Polyommatus icarus) is a butterfly in the family Lycaenidae and subfamily Polyommatinae. The butterfly is found throughout the Palearctic. Butterflies in the Polyommatinae are collectively called blues, from the coloring of the wings. Common blue males usually have wings that are blue above with a black-brown border and a white fringe. The females are usually brown above with a blue dusting and orange spots.

Mating in Buckinghamshire
male left; female right

The Common blue was elected as the national butterfly of Israel in 2023.

license
cc-by-sa-3.0
copyright
Wikipedia authors and editors
original
visit source
partner site
wikipedia EN