Diagnosis. Externally E. turbidella cannot be distinguished from E. albida or E. similigena, although these two are generally paler. The male genitalia are characterised by the short demarcated valval tip, the relatively longer aedeagus (1.22–1.27 × capsule length) and triangular gnathos (Hyperlink).
Female genitalia have prominent widened posterior apophyses, reaching beyond anterior ones and very short and narrow signa (5–6 cells wide, 2.7–5.1 × as long as wide) (Hyperlink). For differences from hannoverella see diagnosis of that species (Van Nieukerken 1985).
Diagnosis: see diagnosis of hannoverella for the differences between it and turbidella. The male genitalia resemble those of klimeschi, but can be recognised by the shape of the valva, with tooth-shaped tip in turbidella, and the asymmetric aedeagus in klimeschi. The female genitalia are very characteristic with the pointed ovipositor, and the long and broad apophyses.
Hostplants: Populus alba L. and P. canescens (Aiton.) Sm., only on the smaller leaves of older shoots of large trees, never on saplings. Material from Potsdam (leg. Hinneberg) is labelled with "Pop.nigr.", but this is probably incorrect. Mine (figs. 476). Egg deposited on side of petiole, about 1½— 2 cm from leaf base. Mine first straight gallery in petiole, causing swelling; final instar larva makes triangular blotch between first lateral vein and leaf margin, or less often between midrib and first lateral vein; frass deposited in two lateral lines, leaving passage for larva, which can withdraw itself in petiole.
Widespread. In Scandinavia in southern Sweden and Denmark only, very local in the extreme east of England, locally abundant throughout central Europe. Some scattered records are known from southern Europe: Spain, Sicily. Finland: Mutanen et al. 2001; Estonia: Jürivete et al. 2000; Latvia: Šulcs and Šulcs 1984; Lithuania: Diškus 2003; Belarus: Merzheevskaja et al. 1976; Bulgaria: Chorbadziev 1915 [overlooked in 1985]; Russia: Jürivete et al. 2000; Nieukerken et al. 2004b. Iran to be removed (see E. albida).
Live history. Univoltine. Larvae start feeding probably in summer, mature larvae can be found in October and November, usually later than hannoverella, often in green islands in fallen leaves. The larva usually feeds in the night. Adults fly from April to June.
This taxonomic description is based on Van Nieukerken (1985) and Van Nieukerken et al (2010)