Phengaris Alcon on:
[Wikipedia]
[Google]
[Amazon]
'', ''Greater large blue">arionides'' ...) by the male bearing on the blue disc of the forewing no other black spots but the discocellular lunule. Central Europe and North Asia, from the coast of the North Sea (Hamburg, Bremen, Belgium) to the Mediterranean, and from France to the Altai, Dauria and Tibet, ab. ''nigra'' Wheel, has the males strongly darkened, the females being quite black above. In ab. ''cecinae'' Hormuz. the ocelli of the underside are absent or strongly reduced. In ab. ''pallidior'' Schultz the margin is grey instead of black. – ''marginepunctata'' Gillm. has a row of black dots before the margin, almost parallel with it; found by Hafner at Loitsch and other places in Carniola.— In the form ''rebeli'' Hirschke the blue of the upperside is more brilliant and more extended, the dark margin being reduced, in the female only the apical area black; Styria. – ''monticola'' Stgr. (83 a) has a narrow black margin like ''rebeli'', but the blue is very deep and dark, so dull as in true ''alcon''; from the Alps of Switzerland and the Caucasus. – Egg white, finely reticulated, laid on the flowers of the food-plant ('' Gentiana pneumonanthe''). The larva generally does not break through the shell on the upperside, so that the holes of empty eggs are not easily noticed. At first grey, later on reddish brown with dark dorsal line and dark head. The butterflies occur on damp meadows where ''Gentiana'' grows; they are plentiful in such places, sometimes even in abundance, from the end of May into July, in the North not before the end of June.
''Phengaris alcon'', the Alcon blue or Alcon large blue, is a
'', ''butterfly
Butterflies are winged insects from the lepidopteran superfamily Papilionoidea, characterized by large, often brightly coloured wings that often fold together when at rest, and a conspicuous, fluttering flight. The oldest butterfly fossi ...
of the family Lycaenidae
Lycaenidae is the second-largest family (biology), family of butterflies (behind Nymphalidae, brush-footed butterflies), with over 6,000 species worldwide, whose members are also called gossamer-winged butterflies. They constitute about 30% of ...
and is found in Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...
and across the Palearctic
The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa.
Th ...
to Siberia
Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states ...
and Mongolia
Mongolia is a landlocked country in East Asia, bordered by Russia to the north and China to the south and southeast. It covers an area of , with a population of 3.5 million, making it the world's List of countries and dependencies by po ...
.
Description from Seitz
''L. alcon'' Schiff. (= areas Esp., ''euphemus'' Godt.) (83 a). Large, the male above deep blue, but without brilliant gloss. The female black-brown, dusted with dark blue in the basal area. The dark violet-grey underside has numerous ocelli. ''L. alcon'' is easily distinguished from the following species (''coeligena'' L. coeligena'' Oberth. China">Caerulea.html" ;"title="'Caerulea">L. coeligena'' Oberth. China ''Scarce large blue">euphemus In Greek mythology, Euphemus (, ''Eὔphēmos'', "reputable") was counted among the Calydonian hunters and the Argonauts, and was connected with the legend of the foundation of Cyrene, Libya, Cyrene. Family Euphemus was a son of Poseidon, ...arcas
In Greek mythology, Arcas (; Ancient Greek: Ἀρκάς) was a hunter who became king of Arcadia. He was remembered for having taught people the arts of weaving and baking bread and for spreading agriculture to Arcadia.
Family
Arcas was the ...
'', '' arion
Arion (; ) was a kitharode in ancient Greece, a Dionysiac poet credited with inventing the dithyramb. The islanders of Lesbos claimed him as their native son, but Arion found a patron in Periander, tyrant of Corinth. Although notable for his mu ...Taxonomy
There are fivesubspecies
In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morpholog ...
:
*''P. a. alcon'' (Central Europe
Central Europe is a geographical region of Europe between Eastern Europe, Eastern, Southern Europe, Southern, Western Europe, Western and Northern Europe, Northern Europe. Central Europe is known for its cultural diversity; however, countries in ...
)
*''P. a. jeniseiensis'' (Shjeljuzhko, 1928) (southern Siberia
Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states ...
)
*''P. a. sevastos'' Rebel & Zerny, 1931 (Carpathians
The Carpathian Mountains or Carpathians () are a range of mountains forming an arc across Central Europe and Southeast Europe. Roughly long, it is the third-longest European mountain range after the Urals at and the Scandinavian Mountains ...
)
*''P. a. xerophila'' Berger, 1946 (Central Europe)
* †'' P. a. arenaria'' (Netherlands
, Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...
)
There has been controversy over whether '' Phengaris rebeli'', currently regarded as an ecotype within the Alcons, should be listed as a separate species. The two types are morphologically indistinguishable and molecular analysis has revealed little genetic difference, mostly attributable to localized habitat adaptation. Still some maintain that they should be treated as distinct species, especially for conservation purposes, because they parasitise different host ant colonies and parasitise these ants at different rates, and also rely on different host plant species (''Gentiana pneumonanthe'' in the case of ''Phengaris alcon'' and ''Gentiana cruciata'' in the case of ''Phengaris rebeli'').
Ecology
The species can be seen flying in mid- to late summer. It lays its eggs onto the marsh gentian ('' Gentiana pneumonanthe''); in the region of theAlps
The Alps () are some of the highest and most extensive mountain ranges in Europe, stretching approximately across eight Alpine countries (from west to east): Monaco, France, Switzerland, Italy, Liechtenstein, Germany, Austria and Slovenia.
...
they are sometimes also found on the related willow gentian ('' Gentiana asclepiadea''). The caterpillars eat no other plants.
Parasitic relationship
Like some other species of Lycaenidae, the larva
A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...
l (caterpillar) stage of ''P. alcon'' depends on support by certain ant
Ants are Eusociality, eusocial insects of the Family (biology), family Formicidae and, along with the related wasps and bees, belong to the Taxonomy (biology), order Hymenoptera. Ants evolved from Vespoidea, vespoid wasp ancestors in the Cre ...
s; it is therefore known as a myrmecophile
file:Panaphis juglandis.jpg , thumb , Myrmecophilous aphids being tended by ants
Myrmecophily ( , ) consists of positive, Mutualism (biology), mutualistic, interspecies Association (ecology), associations between ants and a variety of other or ...
.
Alcon larvae leave the food plant when they have grown sufficiently (4th instar
An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...
, or shedding) and wait on the ground below to be discovered by ants. The larvae emit surface chemicals (allomone
An allomone (from Ancient Greek ' "other" and pheromone) is a type of semiochemical produced and released by an individual of one species that affects the behaviour of a member of another species to the benefit of the originator but not the rec ...
s) that closely match those of ant larvae, causing the ants to carry the Alcon larvae into their nests and place them in their brood chambers. Once adopted into a nest, Alcon larvae are fed the regurgitations of nurse ants (just as other ant brood), a process called trophallaxis
Trophallaxis () is the transfer of food or other fluids among members of a community through mouth-to-mouth (stomodeum, stomodeal) or anus-to-mouth (proctodeum, proctodeal) feeding. Along with nutrients, trophallaxis can involve the transfer of m ...
. This parasitic method is known as the "cuckoo" strategy and is an alternative to the predatory strategy employed by most other members of the genus such as '' Phengaris arion''. Though less common, the cuckoo strategy has been found to have several advantages over the predatory strategy. For one, it is more trophically efficient than preying directly on other ant grubs, and as a result, significantly more cuckoo-type larvae can be supported per nest than predatory larvae. Another advantage of cuckoo feeding is that individuals, having pursued a higher degree of social integration, have a higher chance of surviving when a nest is overcrowded or facing food shortage because ants preferentially feed the larvae; compared to the type of scramble competition that can devastate predatory larvae, this contest competition results in much lower mortality. Though the cuckoo strategy has its advantages, it also comes with important costs; with greater host ant specialization comes much more limited ecological niches.
When the Alcon larva is fully developed it pupates. Once the adult hatches it will leave the ant nest.
Over time, some ant colonies that are parasitized in this manner will slightly change their larva chemicals as a defence, leading to an evolutionary "arms race" between the two species.
Generally, Lycaenidae species which have a myrmecophilous relationship with the ant genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
''Myrmica
''Myrmica'' is a genus of ants within the subfamily Myrmicinae. It is widespread throughout the temperate regions of the Holarctic realm, Holarctic and high mountains in Southeast Asia.
The genus consists of around 200 known species and additio ...
'' are locked to primary host
A host is a person responsible for guests at an event or for providing hospitality during it.
Host may also refer to:
Places
* Host, Pennsylvania, a village in Berks County
* Host Island, in the Wilhelm Archipelago, Antarctica
People
* ...
specificity. The Alcon blue is unusual in this regard in that it uses different host species in different locations throughout Europe, and often uses multiple host species even within the same location and population. Though it may be adopted into the nests of multiple ''Myrmica'' species within a given site, there is typically one "primary" species with which the locally adapted larvae can best socially integrate, leading to drastically higher survival rates. Across Europe, Alcons are known to use '' Myrmica scabrinodis'', '' Myrmica ruginodis'', '' Myrmica rubra'', ''Myrmica sabuleti,'' ''Myrmica schencki,'' and rarely ''Myrmica lonae,'' and ''Myrmica specioides''.
Predation
''P. alcon'' larvae are sought underground by the '' Ichneumon eumerus''wasp
A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder ...
. On detecting a ''P. alcon'' larva the wasp enters the nest and sprays a pheromone that causes the ants to attack each other. In the resulting confusion the wasp locates the butterfly larva and injects it with its eggs. On pupation
A pupa (; : pupae) is the life stage of some insects undergoing transformation between immature and mature stages. Insects that go through a pupal stage are holometabolous: they go through four distinct stages in their life cycle, the stages th ...
, the wasp eggs hatch and consume the chrysalis from the inside.
See also
* '' Orachrysops niobe'' Brenton blue butterfly from South Africa, with a similar life cycleReferences
External links
David Nash pages on ''Maculinea alcon''
Smell-wars between butterflies and ants
{{Taxonbar, from=Q973034 Phengaris Brood parasites Butterflies of Europe Taxobox binomials not recognized by IUCN