{{Short description|Species of moth}} {{Speciesbox | name = Oak eggar | image = Lasiocampa quercus01.jpg | taxon = Lasiocampa quercus | authority = (Linnaeus, 1758) }}

The '''oak eggar''' ('''''Lasiocampa quercus''''')<ref>{{cite book |author1=David Chapman |title=Exploring the Cornish Coast |date=2008 |publisher=Alison Hodge |location=Penzance |isbn=9780906720561 |page=101}}</ref> is a common moth of the family Lasiocampidae found in Europe and northern and western parts of Asia.<ref>{{cite book |url=https://books.google.com/books?id=1TcsdYltXqkC&pg=RA1-PA122 |page=122 |title=A Hand-book to the Order Lepidoptera |volume=4 |author=William Forsell Kirby |publisher=E. Lloyd |year=1897}}</ref> It feeds on a variety of plant species (mainly heather and bilberry), and may develop over two years in higher latitudes, where it may be known as the northern eggar. Its specific name ''quercus'' refers to the fact that its cocoon generally resembles an acorn, not that its primary food source is oak.

==Habitat== The oak eggar's habitat is wide-ranging, including scrub, heath, moor, downland, hedges and sea cliffs, reflecting the larva's very varied range of food plants.<ref name=BC>{{cite web|title=Butterfly Conservation: Oak Eggar/Northern Eggar|url=https://butterfly-conservation.org/1034-1462/oak-eggarnorthern-eggar.html|accessdate=1 April 2018}}</ref>

==Lifecycle== ===Adult=== thumb|left|Mating

The moth's wingspan is about 45&nbsp;mm (male) to 75&nbsp;mm (female), the female being larger and paler than the male. It is Britain's largest day-flying moth.<ref name=Newland>{{cite book|title=Britain's Day-flying Moths|author=Newland, D., Still, R. & Swash, A.|date=2003|publisher=Princeton University Press|isbn=9781400846900|url=https://books.google.com/books?id=Lfct5IG8wEAC&q=oak+eggar+moth|accessdate=1 April 2018}}</ref>

The oak eggar is on the wing for about two months between May and September, depending on the latitude. In more northerly latitudes, development can span two years, with larvae overwintering the first year, and the pupae in the second year. In northern areas it is known as the northern eggar; this was formerly thought to be a separate species, but is generally assumed to be a subspecies ''Lasiocampa quercus callunae'', there is no clear geographical separation of the two types, but the northern eggar tends to be the larger of the two.<ref name=Newland /> There are morphological differences and different food preferences.<ref name=Young>{{cite book|author=Young, M|title=The Natural History of Moths |page=55|date=2010|publisher=Bloomsbury|isbn=9781408149539|url=https://books.google.com/books?id=wgHVBAAAQBAJ&q=oak+eggar+range|accessdate=1 April 2018}}</ref> Males tend to be day fliers, while females tend to fly from dusk.<ref name=Ford>{{cite book|title=Larger British Moths|publisher=Frederick Warne, Observer Series|author=R. L. E. Ford, FRES, FZS|date=1963}}</ref><ref name=UKM>{{cite web|title=UK Moths: Oak eggar|url=http://www.ukmoths.org.uk/species/lasiocampa-quercus|accessdate=1 April 2018}}</ref>

Unpaired females may attract a large number of males, and eggs are laid loosely in undergrowth.<ref name=NS>{{cite book|work=New Scientist|volume=235|date=18 May 1961|pages=392–395|author=George E. Hyde FRES|title=The courtship of moths|url=https://books.google.com/books?id=RUHuMhEP2mEC&dq=oak+eggar+moth&pg=PA394|accessdate=1 April 2018}}</ref>

===Larva=== [[File:Lasiocampa quercus 4th instar caterpillar Keila (side view).jpg|thumb|upright|Fourth-instar caterpillar]] thumb|Cocoon

Larvae feed on a wide variety of plant species, low down, including blackthorn, hawthorn, viburnum, dogwood, ivy and ling,<ref name=Ford /> bilberry, broom, larch, birch, willow, hazel, sea buckthorn and ''Rubus'' species, including bramble. It is not known to feed on oak;<ref name=UKM /> however, one entomologist (Brues, 1924) is quoted as saying:

{{Blockquote|The Oak Eggar caterpillar (''Lasiocampa quercus''), a pest particularly of oak forests, is known to be capable of adapting itself to a variety of trees in default of oak<ref>{{cite book|author=Wardle, R. A.|title=The Problems of Applied Entomology|date=1929|page=4|publisher=Manchester University Press|url=https://books.google.com/books?id=oBENAQAAIAAJ&q=oak+eggar+range|accessdate=1 April 2018}}</ref>}}

Larvae can be infected by a baculovirus, a virus that changes their behaviour, causing them to climb out of the protection of low scrub and leave them open to predation, facilitating the spread of the infection.<ref>{{cite news|work=The Telegraph|title='Zombie virus' outbreak causes caterpillars to explode|url=https://www.telegraph.co.uk/news/2017/08/02/zombie-virus-outbreak-causes-caterpillars-explode/|date=2 August 2017|accessdate=1 April 2018}}</ref><ref>{{cite news|work=BBC News|date=2 August 2017|title=Caterpillars turned into 'exploding zombies' by bug|url=https://www.bbc.co.uk/news/uk-england-lancashire-40800462|accessdate=1 April 2018}}</ref>

The caterpillar hairs of some species of moth, such as the oak processionary moth (''Thaumetopoea processionea''), can cause skin irritation,<ref>{{cite web|title=Forestry Commission: Oak processionary moth (Thaumetopoea processionea)|url=https://www.forestry.gov.uk/oakprocessionarymoth#health|accessdate=1 April 2018}}</ref> but there is no evidence that the oak eggar is one of these, despite the similar name.

===Pupa=== The caterpillar pupates on the ground inside a silken cocoon, the exterior of which is hard and yellowish, and resembles an acorn, hence the moth's name.<ref name=Ford /><ref name=UKM /><ref name=NS /> ''Eggar'' is an obsolete word relating to the shape of the cocoon.<ref>{{cite book|author1-last=Marren|author1-first=Peter|author2-last=Mabey|author2-first=Richard|author1-link=Peter Marren|author2-link=Richard Mabey|title=Bugs Britannica|page=274|url=https://books.google.com/books?id=Ah62bUZLDOwC&dq=oak+eggar+moth&pg=PA274|date=2010|publisher=Random House|isbn=9780701181802|accessdate=1 April 2018}}</ref>

<gallery mode=packed> Lasiocampa_quercus_MHNT_CUT_2011_0_446_female_Mussidan.jpg|Female, dorsal left Lasiocampa quercus MHNT CUT 2011 0 446 Male Bassillac.jpg|Male, dorsal left </gallery> {{Clear}}

==References== {{reflist}}

==External links== {{Commons category|Lasiocampa quercus}} {{Wikispecies|Lasiocampa quercus}} * [https://web.archive.org/web/20160207125321/http://www.faunaeur.org/full_results.php?id=443551 Fauna Europaea] * [http://www.lepiforum.de/lepiwiki.pl?Lasiocampa_Quercus Lepiforum.de] {{in lang|de}} * [http://www.vlindernet.nl/vlindersoort.php?vlinderid=43&vq=Lasiocampa Vlindernet.nl] {{in lang|nl}}

{{Taxonbar|from=Q261053}}

Category:Lasiocampidae Category:Moths described in 1758 Category:Moths of Africa Category:Moths of Asia Category:Moths of Europe Category:Animal taxa named by Carl Linnaeus