Stenopterus rufus is a xerothermic Euro-Turanian species, widespread from Portugal to Turkmenistan, with two "real" subspecies (S. rufus transcaspicus Lazarev, 2008 and S. rufus syriacus Pic, 1892). The third one, S. r. geniculatus Kraatz, 1863), is illusory since specimens with the same characters are also frequently collected from Spain to Germany or the Netherlands, where they are even predominant. Moreover, perfectly typical ones are found in the Balkans, Anatolia and even in the typical series of geniculatus (excerpted from [✧]). The nominotypical subspecies is distributed in warm regions of Central and West Europe and almost whole Mediterranean region.
Larvae of S. rufus develop in dead branches of many deciduous trees and shrubs, pupation in pupal cell in the wood during spring. Life-cycle two years. Adults, active from late spring May to August, are diurnal and anthophilous (typically on Achillea or Apiaceae) [❖].
Body length: 7 - 16 mm
Life cycle: 2 years
Adults in: May - August
Host plant: polyphagous in deciduous trees (Quercus, Castanea, Robinia, Juglans, Prunus, Salix, Pistacia etc.)
Distribution: Austria, Belgium, Bosnia Herzegovina, Bulgaria, Croatia, Czechia, France, Germany, Hungary, Italy, Luxembourg, Malta, Moldavia, Netherlands, Poland, Slovakia, Slovenia, Spain, Russia, Switzerland, Ukraine, Canary Islands