Diagnosis. Ectoedemia quinquella is very similar to E. algeriensis and E. coscoja, but has a dark thorax, at least the anterior part. E. coscoja also differs in having a pale head. Male genitalia similar to those of E. coscoja, valva tip less pronounced; female genitalia compared with E. algeriensis and E. coscoja only with few setae on terminal segments.
Description.
Male. Forewing length 1.84 — 2.28 mm (2.10 ± 0.17, 6), wingspan 4.2 — 5.0 mm. Head: frontal tuft almost completely black, with a few fuscous scales on frons; collar black. Antennae with 36 — 42 segments (39.8 ± 2.6, 4). Thorax black, posterior tips of mesoscutum and tegulae white. Forewings black with three white spots: a costal on ⅓ from wingbase, a dorsal, approximately in middle, and a discal on ⅔ from base, sometimes a few white scales near wingbase. Hindwing with yellowish hair-pencil of approximately ¼ hindwing length, surrounded by yellow lamellar scales.
Female. Forewing length 2.04 — 2.68 mm (2.37 ± 0.19, 8), wingspan 4.6 — 5.6 mm. Antennal segments 26—29 (28.1 ± 1.1,7).
Male genitalia. Capsule length 227 — 266 µm (2). Tegumen rounded, slightly indented at tip. Gnathos with central element divided, distal part spatulate, basal part with serrate margin. Valva length 171—257 µm (2), inner margin concave, except basally, tip narrow, dorsal surface with comparatively few setae. Aedeagus length 171 — 257 µm (3), carinae pointed, single or bifurcate, sometimes with additional spines at base.
Female genitalia. T8 with two lateral groups of scales and few setae, on T7 along anterior margin of T8 a few small setae, not arranged in distinct row. Anal papillae with 12 — 18 setae. Vestibulum with vaginal sclerite, a dorsal spiculate pouch, and a group of densely packed pectinations near entrance of ductus spermathecae. Corpus bursae 550 — 670 µm, without pectinations; signa dissimilar, longest 411 — 514 μm (4), shortest 356 — 454 µm, 4.0 — 4.7 X as long as wide (4). Ductus spermathecae with 2 indistinct convolutions.
Larva. Yellow, with dark brown head-capsule and conspicuous black ventral plates, which are shed during final instar. Thereafter ganglia visible.
Hostplants: Quercus robur L., Q. petraea (Matt.) Liebl., Q. pubescens Willd. (new record).
Mine. Egg on leaf underside, often against vein. Mine highly contorted gallery; early mine filled with narrow linear frass, later with irregular dispersed black frass, leaving wide clear margins. Often many mines occur in the same leaf.
Atlantic-mediterranean species, locally abundant in southern England, known from a small number of localities in Belgium, France, Italy and Greece. Record from Norway (Grönlien, 1937) probably incorrect.
Netherlands: Alders and Donner 1992. A record from Rumania (Căpuşe and Kovacs 1987) needs to be confirmed, the record from Croatia (Laštůvka and Laštůvka 1997) was a mistake. The records from Italy by Jäckh (Van Nieukerken 1985) based on illustrations only, are here confirmed by the study of the original specimens (see below). The species is expanding northwards in Belgium and the Netherlands: Alders 2006; Huisman et al. 2001; Nieukerken 2006; Nieukerken and As 2008.
Life history. Univoltine, larvae occur late in the season, in England in late October and November, in Greece very young larvae have been found in mid September. Adults fly in June and July. Larvae may be confused with those of E. rufifrontella.
This taxonomic description is based on Van Nieukerken (1985) and Van Nieukerken et al (2010).