Species of butterfly
 ;templatestyles src="Template:Taxobox/core/styles.css" / ;
The dusky large blue ("Phengaris nausithous") is a species of butterfly in the family Lycaenidae. It is found in Armenia, Austria, Azerbaijan, Belarus, Bulgaria, Czech Republic, France, Georgia, Germany, Hungary, Kazakhstan, Moldova, Montenegro, the Netherlands, Poland, Romania, Russia, Slovenia, Spain, Switzerland, and Ukraine.
The life cycle of this species is strongly related to the herbaceous plant "Sanguisorba officinalis" (great burnet).
Description from Seitz.
L. arcas Rott. (= erebus Knoch) (83 e). Male similar to "euphemus", but the female quite black-brown above; particularly recognizable by the underside being coffee-brown and bearing only one row of ocelli, ab. "minor" Frey are small specimens from Switzerland. In ab. "inocellata" Sohn the ocelli of the underside are reduced, in ab. "lycaonius" Schultz they are entirely absent. In the male-ab. "lucida" Geest the forewing above has the blue lighter and more extended and the black discal spots reduced or obsolete. Throughout Central Europe, from Alsatia to the Ural, Caucasus and Armenia, and from Pommerania and the Lower Rhine to Italy. — Egg like that of "euphemus" laid on "Sanguisorba". The young larva pale, later on purple-brown and finally probably yellowish-brown, at first at the flowers, later on at the leaves of "Sanguisorba". The butterflies have exactly the same habits as "euphemus", with which they frequently fly together, in July and August; they are usually still more plentiful than "euphemus" in the places where they occur (damp meadows).
References.
 ;templatestyles src="Reflist/styles.css" / ;