Lesser Rock Grayling
by Matt Rowlings
copyright © 2003-2017
Valais, Switzerland, June 2010
Valais, Switzerland, June 2008
Field notes and information
Distribution and identification extremely difficult due to similarity with the rock grayling H. alycone.
Identification & Similar species: This is one of a group of species difficult to identify owing to individual variability. The following descriptions are not fully reliable. Reference to the julien organs surrounding the genetalia is reportedly definitive, but I've not had great success with this.
Woodland grayling, fagi: averagely larger. Internal edge of the underside hindwing white band curved. Underside forewing white band often without significant indent.
Rock grayling, alycone: internal edge of the underside hindwing white band straight (but with an large indent in the middle). Underside forewing white band often with significant indent just below the apical eye spot.
Lesser rock grayling, genava: as rock grayling alcyone. I don't know of a reliable way to separate these two species.
Distribution & Flight: Appears to inhabit all of Italy, Switzerland and east France. Distributional relationship with the rock grayling, H. alcyone , is not fully established due to problems with identification. In Switzerland, the rock grayling is absent which is why I can call these butterflies lesser rock graylings. Flies June/ August.
Habitat & Behaviour: Open woodland with grass. Often rests on tree trunks for shade during the hottest parts of the day and rocks to warm up.
Valais, Switzerland, June 2015
Valais, Switzerland, July 2011
Valais, Switzerland, July 2016