Food Plant: Ulmus glabra (Elm)

Mine: Early Summer onwards

Notes: A full depth blotch mine, which usually starts from the angle formed by the midrib and a vein. The taxonomy of the sawflies feeding on Ulmus is problematic and unresolved at present. Some authors eg Lacourt (2020) consider all the Ulmus feeding leafminers belong to one species - Kaliofenusa pusilla. F.ulmi was recorded in Ireland (2004, Knight) as K. pusilla.
In Europe there are at most two species on Elm, with Fenusa ulmi on Ulmus glabra and Fenusa altenhoferi on U.minor and U.procera. It is not clear whether U.laevis is a host of Fenusa. Fenusa ulmi mines seem to start in the leaf interior and Fenusa altenhoferi from the leaf edge, but perhaps this is not constant and further research needs to be undertaken.

Data: 12.vi.2006 ex mine 05.vi.2006, Zwett, Austria, E.Altenhofer

Image:© Rob Edmunds

References:
Knight, G. T. (2004), Kaliofenusa pusilla (Serville, 1823) (Hymenoptera: Tenthredinidae), species of leaf-mining sawfly new to Ireland, Bulletin of the Irish Biogeographical Society 2004 No.28 pp.61-62 ref.5
Lacourt J, (2020) - Sawflies of Europe, 277