unknown on Bistorta officinalis

Bistorta officinalis, Belgium, Prov. Liège, Butgenbach, RN de la Vallée de la Schwalm © Stéphane Claerebout

same leaf, underside

gall

underside of a leaf, with three occupied galls close together

Cecidomyiid larva on Bistorta officinalis

a singe larva, in drop of digestive liquid

Cecidomyiid larvae on Bistorta officinalis

sometimes two larvae share a gall

larva

gall

one or more inconspicuous bumps on the upper side of the leaves; in the corresponding depression at the underside one (rarely two or three) white cecidomyiid larvae.

hostplants

Polygonaceae, narrowly monophagous

Bistorta officinalis.

According to Buhr rarely also on Persicaria amphibia.

notes

It is not known which species is involved, despite the fact that Buhr, under # 4980, cites several papers referring to this gall.

references

Buhr (1965a).