Swammerdamia caesiella (Hübner, 1796)
Betula spec., Belgium, prov. Limbourg, Genk-de Maten, 24.ix.2016 © Carina Van Steenwinkel: free-living larva
Betula pendula, Belgium, prov. Antwerp, Mol, 27.ix.2014 © Carina Van Steenwinkel: much silk on the leaf
Betula pendula, Lattrop, Bergvennen, 23.viii.2004
Betula sp., Belgium, prov. Limburg, Zutendaal de Lieteberg, 29.ix.2012 © Chris Snyers
young larva with three small mines
The young larva makes one of, more probably, several tiny mines, from which much of the frass is ejected. Part of the frass grains are trapped in a slight spinning under the mine.
Bivoltine, larvae in June-July and September-October; hibernation as pupa.
BE recorded (Phegea, 2012).
NE recorded (Kuchlein & de Vos, 1999a; Microlepidoptera.nl, 2012).
LUX recorded (Fauna Europaea, 2012).
distribution within Europe
All Europe (Fauna Europaea, 2012).
The free living larva is light or dark greyish green with three darker length lines. The larva lives under a slight spinning at the upper side of the leaf, causing window feeding.
These mines were known already for some years, but only in 2012 Chris Snyers succeeded in finding the link to the responsible species. Similar tiny youth mines seem to be a speciality of the family Yponomeutidae.
Agassiz (1996a), Baldizzone (2004a), Bengtsson & Johansson (2011a), Embacher & Kurz (2008b), Friese (1963a), Kuchlein & Donner (1993a), Kuchlein & de Vos (1999a), Leutsch (2011a), Paulavičiūtė (2020a).