Dichotomous table for gallers on Filago
(incl. Logfia, Phagnalon)
by Hans Roskam
1a Leaves at the shoot tip thickened, coalesced to a gall. F. gallica, germanica, minima. Acentrotypus brunnipes
1b Tips of flowering and vegetative shoots distorted, available leaves twisted with inrolled margins, stems shortened; infected with green or yellowish aphids covered with white wax. F. arvensis, germanica, lutescens: Pemphigus populinigrae
1b Terminal swellings of shoots. Phagnalon saxatile, rupestre: Spathulina sicula