{{Short description|Species of moth}} {{Speciesbox | name= Square-spot dart | image = Euxoa obelisca2.jpg | taxon = Euxoa obelisca | authority = [[Michael Denis|Denis]] & [[Ignaz Schiffermüller|Schiffermüller]], 1775 }}
'''''Euxoa obelisca''''', the '''square-spot dart''', is a [[moth]] of the family [[Noctuidae]]. It is found in the [[Palearctic realm]] (Europe, [[Central Asia]], [[North Africa]] [[Asia minor]]). [[Image:Euxoa obelisca1.jpg|thumb|left|200px|Mounted]]
==Technical description and variation== {{Entomology glossary hatnote}} Forewing purplish brown; costa pale to outer line: cell dark brown; stigmata large, greyish ochreous: the claviform dark; hindwing in male white, with narrow grey shade along margin, in female more or less grey-tinged throughout.- in ab. ''[[Euxoa aquilina|fictilis]]'' Hbn. the forewing is more variegated, the submarginal line preceded by a row of distinct black teeth; - ab. ''[[Euxoa temera|ruris]]'' Hbn., larger than typical, reddish grey or reddish brown, with or without the pale costa: stigmata large and pale: - ab. ''[[Euxoa temera|villiersii]]'' Guen. is also larger than typical; forewing ochreous grey with costa and both stigmata whitish, darker in the female; — ab. ''plectoides'' Guen. the same size as type, forewing with more acute apex, deep shining violet brown, with traces of subterminal only: costa and stigmata (which are small) pale testaceous; the orbicular somewhat angulated, the reniform constricted in middle: claviform obsolete: the cell deep black; hindwing very dark; described from a female only from Lapland; omitted by Staudinger, but probably a distinct species: a very distinct form from the Urals, which may be called ab. ''carbonis'' nov.[Warren] has the ground colour purplish black, with the costal streak and upper stigmata pale and the cell deep black: all the lines indistinct: several examples of both sexes sent from Uralsk by M. Bartel.<ref>Seitz, A. Ed., 1914 ''Die Großschmetterlinge der Erde'', Verlag Alfred Kernen, Stuttgart Band 3: Abt. 1, Die Großschmetterlinge des palaearktischen Faunengebietes, Die palaearktischen eulenartigen Nachtfalter, 1914</ref> [[Image:Buckler W The larvæ of the British butterflies and moths PlateLXXII.jpg|thumb|140px|left|Figs 4, 4a larva after last moult]] The caterpillar is obscure greyish or brownish, with a dark-edged pale line along the middle of the dorsum, and a dusky line on each side of it; low down on the sides is another dusky line.
==Biology== The moth flies from July to October depending on the location.
The larvae feed on various herbaceous plants, such as ''[[Helianthemum nummularium]]'' and ''[[Galium]]'' species.<ref>{{cite web|url= http://www.nhm.ac.uk/research-curation/research/projects/hostplants/ |title= Robinson, G. S., P. R. Ackery, I. J. Kitching, G. W. Beccaloni & L. M. Hernández, 2010. HOSTS – A Database of the World's Lepidopteran Hostplants. Natural History Museum, London.}}</ref>
==Similar species==
''Euxoa obelisca'' is difficult to certainly distinguish from its congeners. See Townsend et al.<ref>Martin C. Townsend, Jon Clifton and Brian Goodey (2010). [https://butterfly-conservation.org/uploads/Difficult_species_guide_page_44.pdf ''British and Irish Moths: An Illustrated Guide to Selected Difficult Species'']. (covering the use of genitalia characters and other features) Butterfly Conservation.</ref> *''[[Euxoa tritici]]'' (Linnaeus, 1761) *''[[Euxoa nigricans]]'' (Linnaeus, 1761) *''[[Euxoa cursoria]]'' (Hufnagel, 1766)
==References== {{Reflist}}
==External links== {{Commons category|Euxoa obelisca}} *[http://www.lepiforum.de/cgi-bin/lepiwiki.pl?Euxoa_Obelisca Lepiforum] *[http://www.nic.funet.fi/pub/sci/bio/life/insecta/lepidoptera/ditrysia/noctuoidea/noctuidae/noctuinae/euxoa/index.html Funet] Taxonomy *[https://fauna-eu.org Fauna Europaea] *[https://web.archive.org/web/20120910223759/http://waarneming.nl/soort.php?id=10009 waarneming.nl {{in lang|nl}}] *[http://www.vlindernet.nl/vlindersoort.php?vlinderid=512 Vlindernet {{in lang|nl}}] *[https://ukmoths.org.uk/show.php?id=3315 Square-spot dart at UKmoths]
{{Taxonbar|from=Q1945677}}
[[Category:Moths described in 1775]] [[Category:Euxoa]] [[Category:Moths of Africa]] [[Category:Moths of Asia]] [[Category:Moths of Europe]] [[Category:Taxa named by Michael Denis]] [[Category:Taxa named by Ignaz Schiffermüller]]