Tetraneura ulmi (Linnaeus, 1758)
Ulmus glabra, Zeewolde, Harderbos © Hans Jonkman
Ulmus x hollandica, Biddinghuizen, Spijk- en Bremerbergbos © Hans Jonkman: two very young galls in an already extensively disfigured leaf (May 3)
same leaf, eight days later; one of the two galls has been aborted
Ulmus minor, Belgium, prov. Liège, Hergenrath, Hohnbach © Jean-Yves Baugnée; jonge gal
Ulmus minor, Amsterdam, Vliegenbos: openings in the old gall
when the gall is sliced open the inside is hidden by a dense tuft of wax threads
after removal of the wax the winged and apterous aphids are visible
Ulmus, Belgium, prov. Namur, Vierves-sur-Viroin, RN Mine de Barytrine © Stéphane Claerebout
this gall did not contain hardly any wax
Ulmus, Zwolle © Arnold Grosscurt: young (failed?) gall.
underside of the galled region.
Ulmus glabra, Zeewolde, Harderbos © Hans Jonkman: in mid-July the galls are vacated and withered; the leaf itself remains green.
Ulmus glabra, Zeewolde, Harderbos © Hans Jonkman. This picture was taken on August 8th, 2015, at a date that other galls of this species were completely withered: an enigmatic late appearance of the spring generation.
same plant and locality, September 18th!
Ulmaceae, narrowly monophagous
Ulmus minor, glabra.
Rarely on U. davidiana, laevis.
the effect of the galling extends far beyond the gall itself, as yellow spots at the upperside of the leaf, and as an extensive hairiness at the underside. Possibly this hypophyllous “erineum” has created the suggestion of the work of a gall mite (Buhr’s # 7325 “unresolved gall mite”).
From the second half of the summer apterae live on the roots of various grasses.
“Agropyron”, Bromus, Dactylis, Deschampsia, Festuca, Holcus, Hordeum, Lolium, Poa, Zea ……
Byrsocrypta ulmi; B. personata Börner, 1950.
Béguinot (2001c, 2002d, 2003a, 2006c, 2012a), Bellmann (2012a), Blackman & Eastop Braggion (2013a), Buhr (1965a), Carter & Danielsson (1993a), Chinery (2011a), Cogolludo (1921a), Coulianos & Holmåsen (1991a), Dauphin & Aniotsbehere (1997a), Deckert & Deckert (2016a), Dietrich (2016a), Ecott (2012a), Heie (1980a), Hellrigl (2004a), Ilie & Marinescu (2011a), Kollár (2011a), Koops (2013a), Kowalski (2004a), Lambinon & Schneider (2004a), Lampel & Meier (2003a), Lehmann & Flügel (2012a), Lehmann & Hannover (2016a), Pellizzari (2010a), Pérez Hidalgo & Umaran del Campo (2013a), Rakauskas & Trukšinaitė (2011a), Redfern & Shirley (2011a), Roskam (2009a), Salas-Remón, Llimona, Lozano ao (2015a) Stefănescu (2009a), Sylvén (1960a), Tambs-Lyche & Heie (1994a), Tomasi (2003a, 2012a), Walczak, Borowiak-Sobkowiak & Wilkaniec (2017a).