Marsh fritillary

{{Short description|Species of butterfly}} {{Use dmy dates|date=December 2019}} {{Speciesbox | name = ''Euphydryas aurinia'' | image = {{CSS image crop|Image=Marsh fritillary (Euphydryas aurinia) male.jpg|bSize=260|cWidth=220|cHeight=140|oTop=10|oLeft=20|Location=center}} | image_caption = Male ''E. a. aurinia'', Dorset | image2 = {{CSS image crop|Image=Marsh fritillary (Euphydryas aurinia) female underside.jpg|bSize=260|cWidth=220|cHeight=140|oTop=20|oLeft=20|Location=center}} | image2_caption = Female ''E. a. aurinia'', Dorset | status = LC | status_system = IUCN3.1 | status_ref = <ref name=IUCN>{{cite iucn |display-authors=3 |last=van Swaay |first= C. |last2=Wynhoff |first2= I. |last3=Wiemers |first3= M. |last4=Katbeh-Bader |first4= A. |last5=Power |first5= A. |last6=Benyamini |first6= D. |last7=Tzirkalli |first7= E. |last8=Balletto |first8= E. |last9=Monteiro |first9= E. |author10=Karaçetin, E. |last11=Franeta |first11= F. |last12=Pe'er |first12= G. |last13=Welch |first13= H. |last14=Thompson |first14= K. |last15=Pamperis |first15= L. |last16=Dapporto |first16= L. |last17=Šašić |first17= M. |last18=López Munguira |first18= M. |last19=Micevski |first19= N. |author20=Dupont, P. |last21=Garcia-Pereira |first21= P. |last22=Moulai |first22= R. |last23=Caruana |first23= R. |last24=Verovnik |first24= R. |last25=Bonelli |first25= S. |last26=Beshkov |first26= S. |year=2014 |title=''Euphydryas aurinia'' |volume=2014 |article-number=e.T174182A53714349 |doi= |access-date=29 October 2021}}</ref> | taxon = Euphydryas aurinia | authority = (Rottemburg, 1775) |synonyms_ref=<ref>[http://www.lepiforum.de/lepiwiki.pl?Euphydryas_Aurinia ''Euphydryas aurinia'' (Rottemburg, 1775) Goldener Scheckenfalter]. Lepiforum.de</ref> |synonyms={{collapsible list|bullets = true |''Papilio artemis'' Denis & Schiffermüller, 1775 |''Papilio maturna'' Esper, 1777 |''Papilio lye'' Bergsträsser, 1780 |''Papilio koloswarensis'' Piller & Mitterpacher, 1783 |''Papilio matutina'' Thunberg, 1791 |''Papilio merope'' De Prunner, 1798 |''Melitaea brunnea'' Tutt, 1896 |''Melitaea ochrea'' Tutt, 1896 |''Melitaea virgata'' Tutt, 1896 |''Melitaea nana'' Rehfons, 1910 |''Melitaea turbida'' Gélin & Lucas, 1912 |''Melitaea unipuncta'' Kiefer, 1916 |''Melitaea hoffmanni'' Kiefer, 1916 |''Melitaea semifuscata'' Cabeau, 1919 |''Melitaea epimolpadia'' Reverdin, 1919 |''Melitaea didyma'' Heinrich, 1923 |''Melitaea rectiangula'' Cabeau, 1924 |''Melitaea catherini'' Le Charles, 1924 |''Melitaea perianthes'' Cabeau, 1926 |''Melitaea interligata'' Derenne, 1926 |''Melitaea gracilens'' Cabeau, 1927 |''Melitaea geminifasciata'' Cabeau, 1927 |''Melitaea transversa'' Cabeau, 1928 |''Melitaea deficiens'' Cabeau, 1928 |''Melitaea leucophana'' Cabeau, 1928 |''Melitaea frigescens'' Verity, 1928 |''Melitaea moritura'' Verity, 1928 |''Melitaea debilisprovincialis'' Verity, 1928 |''Melitaea valentini'' Nitsche, 1928 |''Melitaea semigriseis'' Cabeau, 1931 |''Melitaea tetramelana'' Cabeau, 1931 |''Melitaea semigracilens'' Cabeau, 1931 |''Melitaea melanoleuca'' Cabeau, 1932 |''Melitaea flavofasciata'' Hackray, 1934 |''Melitaea insterburgia'' Braun, 1937 |''Euphydryas albofasciata'' Frohawk, 1938 |''Euphydryas suffusa'' Frohawk, 1938 |''Melitaea infra-rectiangula'' Caruel, 1939 |''Melitaea ocellata'' Caruel, 1944 |''Melitaea arcuata'' Caruel, 1944 |''Melitaea commacula'' Caruel, 1944 |''Melitaea ligata'' Caruel, 1944 |''Melitaea splendida'' Mauny, 1949 }}}} The '''marsh fritillary''' (''Euphydryas aurinia'') is a butterfly of the family Nymphalidae. Commonly distributed in the Palearctic region, the marsh fritillary's common name derives from one of its several habitats, marshland. The prolonged larval stage lasts for approximately seven to eight months and includes a period of diapause over the winter. The larvae are dependent on the host food plant ''Succisa pratensis'' not only for feeding but also for hibernation, because silken webs are formed on the host plant as the gregarious larvae enter hibernation. Females lay eggs in batches on the host plant and are, like other batch-layers, selective about the location of oviposition because offspring survivorship levels for batch-layers are more tied to location selection than they are for single-egg layers.

As of 2019 the butterfly's global conservation status is considered of least concern, but it has faced rapid decline and is considered regionally vulnerable or endangered over much of its range.

== Taxonomy == ''E. aurinia'' is represented by many subspecies. The most widely accepted are: * ''Euphydryas aurinia aurinia'' central Europe, southern Europe, western Siberia * ''Euphydryas aurinia bulgarica'' (Fruhstorfer, 1916) <ref>Fruhstorfer, H. 1917 Neue Rhopaloceren aus der Sammlung Leonhard ''Archiv Naturg''. 82 A (2) : 1-28, pl. 1 </ref> Carpathian Mountains * ''Euphydryas aurinia laeta'' (Christoph, 1893) <ref>Christoph, H. T. 1893 Lepidoptera Nova Faunae Palaearcticae ''Dt. Ent. Z. Iris'' 6 (1) : 86-96</ref> central Siberia, Altai, Sayan, Transbaikal * ''Euphydryas aurinia beckeri'' (Lederer, 1853) <ref> Lederer, J. 1853 Versuch die europäischen Lepidopteren (einschlissig der ihrem Habitus nach noch zure europäischen Fauna gehörigen Arten Labradors, der asiatischen Türkei un des asiatischen Russlands) in möglichst natürliche Reihenfolge zu stellen, nebst Bemerkungen zu eineg Familien und Arten. Rhopaloceren & Heteroceren ''Verh. zool.-bot. Ver. Wien'' 2 (Abh.) : 14-54 (Rhopaloceren)</ref> Morocco (Middle Atlas, Rif Mountains) submarginal band of the hindwing is of a magnificent deep russet-red colour and nearly occupies the whole outer half of the wing, being outwardly bordered by black lunules centred with pale yellow<ref>{{citation-attribution|1=Seitz, A. ed. Band 1: Abt. 1, ''Die Großschmetterlinge des palaearktischen Faunengebietes, Die palaearktischen Tagfalter'', 1909, 379 Seiten, mit 89 kolorierten Tafeln (3470 Figuren) }}</ref> * ''Euphydryas aurinia barraguei'' (Betz, 1956) <ref> Betz, J.-T. (1956). ''Melitaea aurinia'' Rott. en Algérie. ''Revue française de Lépidoptérologie'', 15 (6): 144.</ref> Algeria * ''Euphydryas aurinia provincialis'' (Boisduval, 1828) <ref>Boisduval, J. B. 1828 ''Europaeorum Lepidopterorum Index Methodicus'': 1-103</ref> (France and northern Italy) * ''Euphydryas aurinia debilis''(Oberthür, 1909) <ref> Oberthür, C. 1909 Notes pour servir à établir la Faune Francaise et Algeriénne des Lépidoptères ''Étud. Lépid. Comp''. 3 : 101-400, 405-415, pl. 11,16-20,23-26 </ref> Mountainous areas like Pyrenees and Alps but the total number of described subspecies is much higher, especially in the eastern Palaearctic. The insect may be best considered a superspecies. <ref>Korb, S.K. & Bolshakov, L.V. 2011a. Taxonomic notes upon the genus ''Euphydryas'' Scudder, 1872 (Lepidoptera: Nymphalidae). ''Eversmannia''25-26: 25-33.</ref>

''E.aurinia '' is in the subgenus '''''Eurodryas''''' The clade members are: * ''Euphydryas aurinia'' (Rottemburg, 1775) * ''Euphydryas provincialis'' (Boisduval, 1828) * ''Euphydryas orientalis'' (Herrich-Schäffer, 1851) * ''Euphydryas asiatica'' (Staudinger, 1881) * ''Euphydryas sibirica'' (Staudinger, 1871) * ''Euphydryas laeta'' (Christoph, 1893) * ''Euphydryas desfontainii'' (Godart, 1819)

Marsh fritillary (Euphydryas aurinia estonica).jpg|''E. a. estonica'', Estonia (MHNT) Euphydryas aurinia beckeri - Calar Alto, Andalousie, Espagne - male dorsal.jpg| ''Euphydryas aurinia beckeri'' ♂ (MHNT) Euphydryas aurinia beckeri - Calar Alto, Andalousie, Espagne - male ventral.jpg|''Euphydryas aurinia beckeri'' ♂ △ (MHNT) Euphydryas aurinia debilis - Pologne - male dorsal.jpg|''E. a. debilis'' ♂ (MHNT) Euphydryas aurinia debilis - Pologne - male ventral.jpg| ''E. a. debilis'' ♂ △ (MHNT) Euphydryas aurinia provincialis - La Motte Var France - male dorsal.jpg|''E. a. provincialis'' ♂ (MHNT) Euphydryas aurinia provincialis - La Motte Var France - male ventral.jpg|''E. a. provincialis'' ♂ △ </gallery>

== Description == ''Euphydryas aurinia'' has a wingspan of {{convert|30|-|42|mm}} in males.<ref name="CC">{{Cite web |url=http://www.butterfly-guide.co.uk/species/fritillaries/ukl11.htm |title=Butterfly Guide by Matt Rowlings |access-date=30 January 2017 |archive-url=https://web.archive.org/web/20180527113955/http://butterfly-guide.co.uk/species/fritillaries/ukl11.htm |archive-date=27 May 2018 }}</ref> The females are usually larger than the males, with a wingspan of {{convert|40|-|50|mm}}.<ref name="DD">[http://www.ukbutterflies.co.uk/species.php?species=aurinia Marsh Fritillary ''Euphydryas aurinia'']. UK Butterflies</ref> These small butterflies are variable in markings and colouration, with many forms and subspecies. The adult butterflies usually show a chequered pattern of brown, orange, and yellow markings. Silver markings are present on the hindwing edge. The underside of the wings is patterned with yellow, orange, and brown without any silver colouration at all.<ref>[https://books.google.com/books?id=79MSnjLtHoEC&pg=PT202 ''RSPB Wildlife of Britain'']. Dorling Kindersley Ltd, 2011, p. 220, {{ISBN|1405369965}}</ref> The eggs are yellow, and easily identified because of the large batch size. The larvae are black.

<gallery mode="packed" heights="180"> File:Euphydryas aurinia MHNT CUT 2013 3 26 Clermont le Fort Dorsal.jpg|Dorsal side File:Euphydryas aurinia MHNT CUT 2013 3 26 Clermont le Fort Ventral.jpg|Ventral side </gallery>

==Distribution and habitat==

This species is widespread in the Palearctic realm, from Ireland in the west to Yakutia in the east, and to north-west China and Mongolia in the south.<ref name="AA">[http://www.nic.funet.fi/pub/sci/bio/life/insecta/lepidoptera/ditrysia/papilionoidea/nymphalidae/nymphalinae/euphydryas/index.html ''Euphydryas'' Scudder, 1872]. Funet</ref><ref>[https://web.archive.org/web/20160304194953/http://www.faunaeur.org/full_results.php?id=441632 Fauna europaea]</ref> The marsh fritillary is in decline in Europe and it is one of eleven butterflies covered by the United Kingdom Biodiversity Action Plan.{{Citation needed|date=November 2019}} Within the British Isles, it is more frequent in the south and west, but especially in Wales where there is a stronghold. <ref name="BB">[http://jncc.defra.gov.uk/protectedsites/SACselection/species.asp?FeatureIntCode=S1065 1065 Marsh fritillary butterfly ''Euphydryas (Eurodryas, Hypodryas) aurinia''] {{Webarchive|url=https://web.archive.org/web/20181119025049/http://jncc.defra.gov.uk/ProtectedSites/SACselection/species.asp?FeatureIntCode=S1065 |date=19 November 2018 }}. Joint Nature Conservation Committee UK</ref>

This species lives in calcareous grassland, in woodland clearings, in damp marshy areas (hence the common name), and in heathy grassland, dominated by tussock forming grasses, including purple moor and rush pastures. In Finland, ''E. aurinia'' has been shown to favor semi-permanent grasslands and impermanent clearcuts in the forest. Young clearcuts were preferred over old clearcuts due to the dense growth of vegetation in old clearcut forests.<ref name=":0">{{Cite journal|last1=Wahlberg|first1=Niklas|last2=Klemetti|first2=Teemu|last3=Hanski|first3=Ilkka|date=1 April 2002|title=Dynamic populations in a dynamic landscape: the metapopulation structure of the marsh fritillary butterfly|journal=Ecography|language=en|volume=25|issue=2|pages=224–232|doi=10.1034/j.1600-0587.2002.250210.x|bibcode=2002Ecogr..25..224W }}</ref> In the United Kingdom, two types of grasslands can be inhabited by ''E. aurinia'': damp grasslands that are either neutral or acidophilus and dry grasslands that have an abundance of plants growing in lime-rich soil (calcicolous grasslands).<ref name=":1">{{Cite thesis|url=https://ore.exeter.ac.uk/repository/bitstream/handle/10036/3223/SmeeM.pdf?sequence=2|title=Population Ecology and Genetics of the Marsh Fritillary Butterfly ''Euphydryas aurinia''|last=Smee|first=Melanie R.|date=June 2011 |type=PhD thesis |publisher=University of Exeter}}</ref> These butterflies can reach an elevation of {{convert|10|-|2200|m}} above sea level.<ref name=DD/>

In the British Isles, the marsh fritillary is usually found in damp, heathy grasslands that are called ''rhos pastures,'' from the Welsh word ''{{lang|cy|rhos}}'' meaning heath. Small populations can be an important element of the ecology because they produce many mobile individuals which can then found other populations. The marsh fritillary is protected under UK law, listed under Schedule 5 of the Wildlife and Countryside Act, and the EU Habitats and Species Directive (Annex II).<ref name="BB" /> The Devon Wildlife Trust owns a number of sites at which it monitors this species. Examples include Stowford Moor (near Holsworthy, Devon), Dunsdon nature reserve (near Bude), Mambury Moor (near Great Torrington), Vealand Farm nature reserve (near Holsworthy), and Volehouse Nature Reserve (near Holsworthy). In 2009, population counts had significantly increased from years 2007 and 2008.<ref>''Wild Devon The Magazine of the Devon Wildlife Trust'', p. 8, Winter 2009 edition</ref> In 2018, a breeding population was found in Carmarthenshire, Wales, after an absence of 50 years.<ref>{{cite news|work=BBC News|date=4 October 2018|title=Rare butterfly returns to Carmarthenshire after 50-year absence|url=https://www.bbc.co.uk/news/uk-wales-45747052|access-date=4 October 2018}}</ref>

In Lithuania (included into the Lithuanian Red Data Book since 2000, red list category-3 (R))(Rašomavičius, 2007) is protected insect species.<ref>{{Cite web|url=https://www.nationalredlist.org/species-information/?speciesID=218505|title=Euphydryas aurinia {{!}} Species Information {{!}} Regional Red List|website=www.nationalredlist.org|access-date=2020-02-03|archive-date=16 April 2021|archive-url=https://web.archive.org/web/20210416022822/https://www.nationalredlist.org/species-information/?speciesID=218505|url-status=dead}}</ref> Euphydryas aurinia usually is found in natural and seminatural moist or wet oligotrophic grasslands (purple moorgrass and heath rush meadows), base rich fens, mostly in Eastern, North-Western and Central Lithuania, where its main foodplant Succisa pratensis (Dipsacaceae) is abundant. Inhabited patches frequently are situated along woodland edges or surrounded by bushes. Species is not found in Southern Lithuania where sandy soils predominate and in South-Western Lithuania where agriculture is very intensive.<ref>{{Cite journal|last=Švitra|first=Giedrius|title=New data on the distribution of ''Euphydryas aurinia'' (ROTTEMBURG, 1775)(Lepidoptera, Nymphalidae) in Lithuania|journal=New and Rare for Lithuania Insect Species|volume=21|pages=112–120|url=http://www.entomologai.lt/leidiniai/category/27-volume-21-2009?download=88:vol-21-p-112-120-svitra-g-new-data-on-the-distribution-of-euphydryas-aurinia-lepidoptera-nymphalidae-in-lithuania|archive-date=29 October 2021|access-date=29 October 2021|archive-url=https://web.archive.org/web/20211029065659/http://www.entomologai.lt/leidiniai/category/27-volume-21-2009?download=88:vol-21-p-112-120-svitra-g-new-data-on-the-distribution-of-euphydryas-aurinia-lepidoptera-nymphalidae-in-lithuania|url-status=dead}}</ref>

In Croatia, it is only present in the north, and even those findings are only historical. Attempts to confirm its presence have failed, but northern Ivanščica and the Lobor valley are considered promising.<ref>{{cite journal |date=2017-12-31 |first1=Toni |last1=Koren |first2=Boris |last2=Lauš |first3=Martina |last3=Šašić |first4=Iva |last4=Mihoci |first5=Ana |last5=Štih |first6=Petra |last6=Bralić |first7=Stanislav |last7=Gomboc |title=Contribution to the Knowledge of the Butterfly Fauna (Lepidoptera: Papilionoidea) of Hrvatsko Zagorje, Croatia |pages=167–196 |url=https://hrcak.srce.hr/191533 |doi=10.20302/NC.2017.26.15 |journal=Natura Croatica: Periodicum Musei Historiae Naturalis Croatici |eissn=1848-7386 |volume=26 |issue=2}}</ref>{{rp|182}}

=== Factors for optimal habitat === The availability of larval food plant ''S. pratensis'' and grass height are the most important factors in providing an optimal habitat for ''E. aurinia''.

==== Host plant availability ==== Because caterpillars live in communal webs formed around their host plant and hibernate through the winter inside the web, the density of host plant is a crucial factor in forming the habitat of ''E. aurinia''. Studies have shown that the density of host plant is directly correlated to the number of larval webs found, which in turn is directly related to the number of adult butterflies. Therefore, a habitat suitable for the larvae can indirectly influence the proliferation of adult butterflies.<ref name=":1" />

==== Sward height ==== Not only is the density of host plant crucial for a favorable habitat, but also the height of the sward, the expanse of grass covering the area where ''E. aurinia'' lives. Sward height that is too short can lead to increased exposure of the larvae to predators and can cause limited food availability, leading to starvation. However, if the sward height is too tall and densely packed, then it becomes difficult for adult butterflies to locate the host plant to oviposit on. Thus, the level of sward height is most optimal when it is medium height.<ref name=":1" />

==Food resources==

=== Host plant for caterpillars === The caterpillars are known to feed primarily on ''Succisa pratensis'' and species of ''Digitalis'', ''Plantago lanceolata'', ''Knautia arvensis'', ''Scabiosa succisa'', ''Scabiosa columbaria,'' ''Veronica'' (''Veronica dubravnaya'', etc.), ''Geranium'', ''Sambucus'', ''Gentiana'', ''Valeriana'', ''Lonicera implexa'', ''Filipendula'', ''Spiraea'' and ''Viburnum''.<ref name="AA" />

==== Methanol emission from feeding ==== One study measuring the level of volatiles released by plants that are consumed by herbivores has shown that huge amounts of methanol and other volatile substances (monoterpenes, sesquiterpenes and lipoxygenase-derived volatile compounds) are emitted by ''E. aurinia'' caterpillars feeding on the host plant ''S. pratensis''. Methanol is a biochemically active compound that is commonly released by metabolic activities of anaerobic bacteria.<ref name=":2">{{Cite journal|last1=Peñuelas|first1=Josep|last2=Filella|first2=Iolanda|last3=Stefanescu|first3=Constantí|last4=Llusià|first4=Joan|date=2005|title=Caterpillars of ''Euphydryas aurinia'' (Lepidoptera: Nymphalidae) feeding on ''Succisa pratensis'' leaves induce large foliar emissions of methanol|journal=New Phytologist|language=en|volume=167|issue=3|pages=851–857|doi=10.1111/j.1469-8137.2005.01459.x|pmid=16101921|doi-access=free |bibcode=2005NewPh.167..851P }}</ref>

=== Adult feeding === Adult butterflies feed on nectar opportunistically, so the density of host plant ''S. pratensis'' does not affect adult butterfly feeding. In fact, by the time adult butterflies emerge, ''S. pratensis'' does not even flower.<ref name=":1" /> Adults are polyphagous and generally feed on ''Ranunculus'' ssp., ''Cirsium'' ssp., ''Leucantherum vulgare'', ''Myosotis'' ssp., ''Rubus'' ssp most often.<ref name=":7">{{Cite journal|last1=Schtickzelle|first1=Nicolas|last2=Choutt|first2=Julie|last3=Goffart|first3=Philippe|last4=Fichefet|first4=Violaine|last5=Baguette|first5=Michel|date=2005|title=Metapopulation dynamics and conservation of the marsh fritillary butterfly: Population viability analysis and management options for a critically endangered species in Western Europe|journal=Biological Conservation|volume=126|issue=4|pages=569–581|doi=10.1016/j.biocon.2005.06.030|bibcode=2005BCons.126..569S }}</ref> They have also been observed feeding on ''Caltha palustris'', also known as kingcup or marsh-marigold, and ''Ajuga reptans'', also known as bugle or bugleweed.<ref>{{Cite book|title=Pocket guide to butterflies |last1=Gibbons|first1=Bob |last2=Revels |first2= Richard |isbn=978-1-4729-1594-8|location=London|oclc=903644054|date = 12 March 2015}}</ref>

== Parental care ==

=== Oviposition discrimination === ''E. aurinia'' females are batch-layers, meaning they lay a large number of eggs at one site. Because 200–300 eggs are at stake every time an egg-laying site is chosen, batch-laying females tend to undergo a discrimination phase in searching for a location to lay eggs on. Each plant can serve as an egg-laying site for four to five clusters of eggs, meaning that more than a thousand larvae may hatch on a single plant. If so, the newly hatched larvae will face serious food shortage and fierce competition for food, which has huge repercussions for offspring survivorship. Therefore, ''Euphydryas'' and other batch-laying females, such as ''Melitaeini'' females, spend more time choosing a place to lay eggs and are more selective when looking for a host plant.<ref name=":3">{{Cite journal|last=Stefanescu|first=Constanti|date=2006|title=Females of the specialist butterfly ''Euphydryas aurinia'' (Lepidoptera: Nymphalinae: Melitaeini) select the greenest leaves of ''Lonicera implexa'' (Caprifoliaceae) for oviposition|url=http://www.creaf.uab.es/global-ecology/Pdfs_UEG/stefanescuetalEJE2006.pdf|journal=European Journal of Entomology|volume=103|issue=3|pages=569–574|via=CREAF|doi=10.14411/eje.2006.077|doi-access=free |bibcode=2006EJEnt.103..569S }}</ref>

==== Size of host plant and vegetation density ==== Female oviposition depends largely on the size of host plant as well as density of vegetation cover. Studies have shown that females prefer to lay eggs on large host plants as opposed to smaller plants. This is to prevent food shortage and starvation of the larvae. Also, sparse, open vegetation structure is favored over dense, thick grasslands when the host plant ''S. pratensis'' is used for oviposition.<ref name=":4">{{Cite journal|last1=Anthes|first1=Nils|last2=Fartmann|first2=Thomas|last3=Hermann|first3=Gabriel|last4=Kaule|first4=Giselher|date=2003|title=Combining larval habitat quality and metapopulation structure – the key for successful management of pre-alpine ''Euphydryas aurinia'' colonies|journal=Journal of Insect Conservation|language=en|volume=7|issue=3|pages=175–185|doi=10.1023/A:1027330422958|bibcode=2003JICon...7..175A |s2cid=25096413}}</ref> The presence of a tall non-host plant (e.g. ''Deschampsia caespitosa'') is negatively correlated with egg nests.<ref name=":5">{{Cite journal|last=Konvicka|first=Martin|date=2003|title=Habitat of pre-hibernating larvae of the endangered butterfly ''Euphydryas aurinia'' (Lepidoptera: Nymphalidae): What can be learned from vegetation composition and architecture?|url=http://baloun.entu.cas.cz/~fric/eje_2003_Konvicka.pdf|journal=European Journal of Entomology|volume=100|issue=3|pages=313–322|doi=10.14411/eje.2003.050|doi-access=free |bibcode=2003EJEnt.100..313K }}</ref> Therefore, abandoned meadows with lime-rich soil have been identified as oviposition sites. Often, ''E. aurinia'' will lay eggs at edges of such meadows because the vegetation structure and plant height fit the female butterfly preference for oviposition.<ref name=":4" /> For such reasons, croplands are generally favored over meadows for oviposition because croplands tend to have concentrated numbers of large-sized host plants.<ref name=":8">{{Cite journal|last1=Liu|first1=Wenhua|last2=Wang|first2=Yifei|last3=Xu|first3=Rumei|date=2006|title=Habitat utilization by ovipositing females and larvae of the Marsh fritillary (''Euphydryas aurinia'') in a mosaic of meadows and croplands|journal=Journal of Insect Conservation|language=en|volume=10|issue=4|pages=351–360|doi=10.1007/s10841-006-9009-x|bibcode=2006JICon..10..351L |s2cid=20578728}}</ref>

==== Color of host plant ==== Females prefer to lay eggs on leaves with the highest chlorophyll contents. Therefore, the reflectance and chlorophyll concentration of leaves also affects the choice of oviposition site for ''E. aurinia''. Chlorophyll content (the "greenness" of plants) can be an indicator for increased fitness of the host plant, which in turn will provide optimal growth opportunities for the newly hatched larvae. Females therefore use visual cues to seek out the greenest leaves to lay their eggs on. However, there are also indications that it is not high chlorophyll concentration but the presence of conspecific egg clusters which attracts females to oviposit on a certain leaf.<ref name=":3" />

==== Other favored factors for oviposition ==== In the Czech Republic, the presence of short grasses that can serve a cushion-like function (especially ''Nardus stricta)'' in the vicinity of the host plant was positively correlated with nest numbers. In general, conditions that promote host plant growth and proliferation are also favorable for nests. Dry, acidic conditions with limited nitrogen resources are preferred for nests because these conditions lead to short swards. Short swards facilitate larval basking, and thus is a factor considered by females during oviposition.<ref name=":5" />

==Life cycle== ''Euphydryas aurinia'' is a univoltine species.

thumb|200px|Eggs

=== Egg === The eggs are laid in groups on the underside of leaves in May and June. Up to 350 are laid in a single batch. They turn from pale yellow when first laid, to bright yellow, then crimson, and finally to dark grey just prior to hatching.

thumb|200px|Young caterpillars

=== Caterpillar === The caterpillars hatch in about three weeks from the end of June onwards. There are six instars for ''E. aurinia'' larvae. The first four are gregarious, the first three being prehibernation instars and the fourth being post-hibernation. The first three instars form a communal web around the food plant ''S. pratensis'' and feed on the host plant for about three weeks.<ref name=":2" /> The young caterpillars become conspicuous by the end of August.<ref name="CC" /> In the autumn, they make stronger webs closer to the ground, usually within a dense grass tussock, where they will start to hibernate.

In the spring, the fourth instar emerges from hibernation. All three of the post-hibernation instars bask in the sun. Basking is a behavior in which the instar increases its body temperature using heat from solar radiation. This allows them to be relatively independent of ambient temperature, which promotes faster development.<ref>{{Cite journal|last=Porter|first=Keith|date=1982|title=Basking behaviour in larvae of the butterfly ''Euphydryas aurinia'' |jstor=3544670|journal=Oikos|volume=38|issue=3|pages=308–312|doi=10.2307/3544670|bibcode=1982Oikos..38..308P }}</ref> During this time, they change color from brown to black.

thumb|200px|Pupa

=== Pupa === At the end of the sixth instar, pupae start forming. This occurs in the spring, around the end of March or beginning of April.<ref name=":3" /> Pupation occurs low down deep within grass tussocks or dead leaves.

=== Adult === Adults emerge and undergo the flight period between May and June.<ref name=":3" /> However, in southern regions, they can be on wing starting from late May.<ref name="CC" /><ref>[http://www.butterfly-conservation-armenia.org/euphydryas-aurinia.html ''Euphydryas aurinia'' (Rottemburg, 1775)]. Butterflies Conservation in Armenia</ref> Adults have short life spans, usually lasting about two weeks.<ref name=":0" />

==Migration==

=== Metapopulations === Research on the population dynamics of the marsh fritillary has shown that they live in metapopulations. A metapopulation is defined as a collection of local populations that are connected together as a result of occasional dispersal. Amongst these some will disappear and others will be founded.<ref name="CC" /> An important feature of metapopulations is that there will always be empty habitat within the system. It is possible for the majority of the habitat patches to be empty. The security of suitable places where the butterfly does not presently inhabit is essential to its survival in the long term.

=== Local dispersal === ''E. aurinia'' butterflies tend to exhibit sedentary behavior, which leads to an increase in local dispersal rather than regional or long-distance dispersal. Males are more likely to emigrate than females, and even so, ''E. aurinia'' rarely move to neighboring patches. The average local population size increases as a result of the limited mobility of adult butterflies.<ref>{{Cite journal|last1=Wang|first1=Rongjiang|last2=Wang|first2=Yifei|last3=Chen|first3=Jiejun|last4=Lei|first4=Guangchun|last5=Xu|first5=Rumei|date=1 June 2004|title=Contrasting movement patterns in two species of chequerspot butterflies, ''Euphydryas aurinia'' and ''Melitaea phoebe'', in the same patch network|journal=Ecological Entomology|language=en|volume=29|issue=3|pages=367–374|doi=10.1111/j.0307-6946.2004.00610.x|bibcode=2004EcoEn..29..367W |s2cid=84884834}}</ref> Thus, the fluctuation of one habitat patch population size is unlikely to affect the population size of another habitat patch.<ref name=":6">{{Cite book|title=On the wings of checkerspots: a model system for population biology|date=2004|publisher=Oxford University Press |last1=Ehrlich |first1= Paul R. |last2=Hanski |first2= Ilkka |isbn=978-0-19-515827-4|location=Oxford|pages=164, 171, 225, 228|oclc=314216335}}</ref> The relative turnover rate of extinction and recolonization of previously empty habitat patches is high for ''E. aurinia'', which indicates that extinction of one local population can be balanced by re-colonization of another. Such classic metapopulation characteristics explain why there is greater within-population genetic structuring in ''E. aurinia''.<ref name=":6" />

== Mating == Mating is believed to occur randomly, as shown by the fact that there is no significant deviation from the Hardy-Weinberg equilibrium in ''E. aurinia'' populations.<ref>{{Cite journal|last1=Joyce|first1=Domino A.|last2=Pullin|first2=Andrew S.|date=2003|title=Conservation implications of the distribution of genetic diversity at different scales: a case study using the marsh fritillary butterfly (''Euphydryas aurinia'')|journal=Biological Conservation|volume=114|issue=3|pages=453–461|doi=10.1016/S0006-3207(03)00087-9|bibcode=2003BCons.114..453J }}</ref> Adult males display sedentary behavior, perching on bushes or grass. They observe and seek out females. Females mate once in their short lifetime and lay multiple batches of eggs.<ref name=":7" /> Due to their short lifetime, females mate soon after they emerge from chrysalis. They bear so many eggs that they are unable to fly far distances until they lay the eggs and only crawl to nearby vegetation. Females are larger and less vibrant in color than males.<ref>{{Cite book|title=Britain's butterflies: a field guide to the butterflies of Britain and Ireland |last1=Newland |first1=D. E. |last2=Still |first2= Rob |last3=Swash |first3= Andy |last4=Tomlinson |first4= David |isbn=978-1-4008-6601-4|edition=3rd, fully revised and updated |location=Princeton, New Jersey|oclc=905696306|date = 15 April 2015}}</ref> <gallery widths="240" heights="180"> Marsh fritillaries (Euphydryas aurinia) courting.jpg|Courting Marsh fritillaries (Euphydryas aurinia) mating.jpg|Mating </gallery>

== Enemies == Known predators of ''E. aurinia'' are cuckoos, frogs, and toads, and the ground beetle ''Pterostichus versicolor''. All of these predators prey on the larvae.<ref name=":6" /> The caterpillars are liable to be attacked by the parasitoid wasp ''Apanteles bignellii'', especially in warm spring weather.<ref>{{usurped|1=[https://web.archive.org/web/20080819152851/http://www.learnaboutbutterflies.com/Britain%20-%20Euphydryas%20aurinia.htm Marsh Fritillary]}}. Learn About Butterflies</ref> The parasitoid displays gregarious parasitoid larval behavior, meaning more than one parasitoid progeny can develop fully in or on the host. In fact, three regular generations of ''A. bignelli'' occur in one generation of ''E. aurinia,'' usually between the pupae, adult, and egg stages of the host.<ref>{{Cite journal|last=Porter|first=K.|date= 1983|title=Multivoltinism in ''Apanteles bignellii'' and the influence of weather on synchronisation with its host ''Euphydryas aurinia''|journal=Entomologia Experimentalis et Applicata|language=en|volume=34|issue=2|pages=155–162|doi=10.1111/j.1570-7458.1983.tb03311.x|bibcode=1983EEApp..34..155P |s2cid=84150848}}</ref> Also, parasitoid oviposition behavior is selective, meaning that ''A. bignelli'' is a specialist parasitoid. The percent of host population parasitized varies greatly, ranging from 0 to 80%.<ref name=":6" />

== Symbiosis == Endosymbiotic bacteria ''Wolbachia'' have been detected in 19 United Kingdom populations at 100% prevalence. When tested for phenotypes such as cytoplasmic incompatibility, sex ratio distortion, mutualistic or neutral relationship, there seemed to be no conclusive phenotype of the endosymbiotic bacteria. Although strains closely matched to the identified ''Wolbachia'' bacteria strain were shown to be sex ratio distorters, no sex ratio distortion was observed in the ''E. aurinia'' populations. Therefore, further research needs to be done to conclude what the phenotype of this symbiotic bacteria is. Possible explanation for the stable sex ratio in ''E. aurinia'' despite the presence of ''Wolbachia'' may be the evolution of traits in the host that suppress the ''Wolbachia'' phenotype from being expressed. If this is the case, then the apparent lack of phenotype of the ''Wolbachia'' bacteria can be explained as phenotype suppression.<ref name=":1" />

== Conservation == As of 2021 the butterfly's conservation status is globally considered of least concern by the International Union for Conservation of Nature and Natural Resources.<ref name=IUCN/> However, several areas report regional decreases in population.

=== Fluctuations of the population === Major fluctuations of local patch populations of ''E. aurinia'' have been reported in western England, with the population number reaching peaks in the 1890s and mid 1920s at population sizes around 40,000 and 1,000 respectively. Despite the massive number of larvae and pupae observed during these two periods of maximal population growth, the population frequency of ''E. aurinia'' fluctuated drastically as the number of caterpillars observed dropped as low as 16 caterpillars in 1920 after a "diligent search".<ref>{{Cite journal|last1=Ford|first1=H.D.|last2=Ford|first2=E.B.|date=1930|title=Fluctuation in numbers and its influence on variation in ''Melitaea aurinia'', Rott. (Lepidoptera)|journal=Transactions of the Entomological Society of London|volume=78|issue=2|pages=345–351|doi=10.1111/j.1365-2311.1930.tb00392.x |bibcode=1930EcoEn..78..345F }}</ref><ref>{{Cite book|title=Ecological Genetics |edition=4 |last=Ford|first=E.B.|publisher=Chapman & Hall|year=1975|location=London}}</ref> Thus, ''E. aurinia'' serves as a good indicator of environmental changes due to its vulnerability to habitat changes.

=== Habitat loss === [[File:Natura 2000 - Focus on Marsh Fritillary.webm|thumb|Short film on the Marsh Fritillary by Natural Resources Wales]] As of 2017, rapid decline of the population had been observed in Denmark due to loss of habitat and host plants.<ref name=":9" />

Because the larval stage is highly dependent on the host food plant ''S. pratensis'', decline in the availability of the host plant leads to negative effects on the ''E. aurinia'' population. Decline of natural habitats for ''S. pratensis'' is correlated with decline in the host plant population. Due to cultivation and shift of land use from traditional farming to grazing, the frequency of ''S. pratensis'' populations has declined over the past few years. Damp, basic soil is suitable for high ''S. pratensis'' frequency. Environmental changes such as acidification and eutrophication have led to a decline in available optimal habitat for ''S. pratensis'', and consequently for ''E. aurinia''.<ref name=":9">{{Cite journal|last1=Brunbjerg|first1=Ane Kirstine|last2=Høye|first2=Toke Thomas|last3=Eskildsen|first3=Anne|last4=Nygaard|first4=Bettina|last5=Damgaard|first5=Christian Frølund|last6=Ejrnæs|first6=Rasmus|date=1 July 2017|title=The collapse of marsh fritillary (''Euphydryas aurinia'') populations associated with declining host plant abundance|journal=Biological Conservation|volume=211|issue=Part A|pages=117–124|doi=10.1016/j.biocon.2017.05.015|bibcode=2017BCons.211..117B }}</ref>

As of 2019 the butterfly had become regionally extinct over much of its former range in the UK.<ref name="BB" /> The population size in the UK had decreased by 60% over the period during which records have been kept.<ref name="BB" /> Human activities such as modern farming altered their main habitat – England's damp meadows – and have changed the climate as well. This loss of major habitats has led to fragmentation and isolation of ''E. aurinia'' populations, thus leading to metapopulation formation.{{Citation needed|date=November 2019}} ''E. aurinia'' is more vulnerable to extinction in the small subpopulations that comprise the metapopulation.{{Citation needed|date=November 2019}}

According to the Joint Nature Conservation Committee in 2019, the population has "declined dramatically in Europe and is regarded as endangered or vulnerable in most of its European range," and the remaining populations in the UK and Spain are considered the "European strongholds" for the species.<ref name="BB" />

== Management == Moderate farming activity can be beneficial to the ''E. aurinia'' population because it can lead to sparsely-vegetated, open landscape which is suitable for ''E. aurinia'' larvae.<ref name=":1" /> Research has shown that the female butterflies prefer to lay their eggs in cropland over meadows. This can be explained by the fact that vegetation is less dense and the host plants tend to be larger in size on cropland.<ref name=":8" /> However, excessive landscape changes that come with modern farming techniques can lead to drastic changes in the ''E. aurinia'' population. There have been efforts made to re-introduce butterflies into empty patches of habitat to increase re-colonization, and techniques such as controlled burns and cattle grazing have also been utilized to promote ''E. aurinia'' population growth.<ref name=":1" /> These areas are monitored for indicators of success such as the frequency of larval webs and the frequency of flowers and larval food plant.

=== Grazing === Cattle grazing is a common method which has been adopted in response to the declining ''E. aurinia'' population. An intermediate level of grazing can help maintain moist grasslands, which are optimal for ''S. pratensis'' and ''E. aurinia.'' However, overgrazing can lead to short host plants, which can lead to shortage of food for the newly hatched larvae. Under-grazing can lead to growth of dense, scrubby plants, which is also unsuitable and unfavored by the female butterflies.<ref name=":1" /> The aim is to produce an uneven patchwork of short and long vegetation by the end of the grazing period, between 8 and 25 cm.

=== Swaling === Another common method for conservation efforts is swaling, which is a form of land management where controlled burning is used to prevent overgrowth of vegetation and promote wildlife biodiversity. Though it is a temporary solution, swaling can provide suitable habitat conditions for ''E. aurinia''. Criticism against swaling include the fact that it is only a temporary solution, and the possibility that swaling can kill masses of ''E. aurinia'' larvae if done at the wrong time of the year.<ref name=":1" />

=== Re-introduction of butterflies === Lastly, in extreme cases, efforts to re-introduce ''E. aurinia'' butterflies into empty patches of habitat have been attempted in order to increase the colonization rate. Because this method involves extreme human intervention to promote patch population formation, this method is also a temporary fix and used only in rare, extreme cases of local extinction.<ref name=":1" />

== Bibliography == * Aldwell, B. and Smyth, F. 2013. The Marsh Fritillary (''Euphydryas aurinia'' (Rottemburg, 1775)) (Lepidoptera: Nymphalidae) in Co. Donegal. ''Irish Naturalists' Journal'' '''32''': 53–63 Crory, Andrew.(?) 2016. Fritillary Butterflies. ''The Irish Hare'', Issue: 113. p. 4

==References== {{Reflist}}

==External links== {{Commons category|Euphydryas aurinia}} {{Wikispecies|Euphydryas aurinia}}

* [http://www.schmetterling-raupe.de/art/aurinia_s.htm Schmetterling-raupe.de] * Kimmo Silvonen [http://www.kolumbus.fi/silvonen/lnel/nym2/Eupaurin.htm Larvae of North-European Lepidoptera] {{Webarchive|url=https://web.archive.org/web/20160327080349/http://www.kolumbus.fi/silvonen/lnel/nym2/Eupaurin.htm |date=27 March 2016 }} * McKee, L. 2008. "Bid to halt decline of butterfly". ''Belfast Telegraph''. 18 July 2008. p. 10 (www.belfasttelegraph.co.uk) * Paolo Mazzei, Daniel Morel, Raniero Panfili [http://www.leps.it/indexjs.htm?SpeciesPages/EurodAurin.htm Moths and Butterflies of Europe and North Africa] * Devon Wildlife Trust manages a number of strongholds for the species including Volehouse Moor, Dunsdon, Meshaw Moor and Vealand farm

Category:Euphydryas Category:Butterflies of Africa Category:Butterflies of Asia Category:Butterflies of Europe Category:Species that are or were threatened by habitat loss Category:Butterflies described in 1775 Category:Habitats Directive species Category:Taxobox binomials not recognized by IUCN