Endangered (proposed as a future Red Data Book species) and a priority species under the UK Biodiversity Action Plan. Since 1994, restricted to a single wood in Warwickshire, where present since 1961, formerly found throughout south-east England. Not recorded in Hampshire or on the Isle of Wight since 1993. Wingspan 23-26 mm. The most likely confusion species are S. adelphella
and Pempelia formosa
. S. hostilis
is usually a rather dull-coloured, dark, obscurely marked species, though it is variable, and forms in which the base of the forewing is red- or orange-tinted are very easy to recognise; S. adelphella
differs in the shape of the antemedian bar on the forewing, which angles strongly outward at the dorsum, but in S. hostilis
meets the trailing edge of the forewing more or less at a right angle; P. formosa
is generally slightly smaller than the two Sciota
species, with the two discal marks on the forewing united and almost touching the antemedian line [Goater]. Larva feeds on Aspen, over-wintering as a pupa in a cocoon.