Diagnosis. Male very characteristic by black head and long androconials on hindwing, reaching to 2/3 of fringe along most of hindwing. Only rare dark-headed specimens of the evergreen oak miners (only known from S. ilicifoliella) could be confused, but they have usually longer antennae with more segments (30-35 in S. atricapitella, 39-50 in ilicifoliella).
Females very similar to S. samiatella and the rarer, uniformly coloured S. basiguttella or trojana.
Male genitalia: manica inconspicuous, narrow. Female genitalia: an elongated accessory sac with some more or less sclerotized folds is characteristic; spines of different length, the longer ones on a rounded lobe; ductus spermathecae with 5 convolutions.
Hostplants. Quercus cerris (Szöcs 1977), Q. petraea, Q. pubescens, Q. pyrenaica, Q. robur. A specimen reared from Castanea sativa (Agassiz 1988) proved to be misidentified S. samiatella (J. Langmaid in litt. 2003). In the Czech Republic only found on Q. pubescens (A. & Z. Laštuvka in litt.).
Leafmine. A contorted gallery, frequently near leaf margin and confined to small area; frass usually in a narrow line, often broader in second part. Egg on either side of leaf. Larva pale yellow or almost white, prothorax with dark coloured sclerites (always?), which may help in distinguishing the mine from the similar S. roborella (see photographs in Huisman et al. 2001). Larva described in detail by Gustafsson & Van Nieukerken (1990). Cocoon: red-brown.
Throughout Europe, with a more or less Atlantic-Mediterranean distribution type: becoming rarer or absent in the North, with only very scattered records in southwestern Scandinavia. The records in Lithuania are outliers in that respect: it is very scarce in that country (R. Puplesis in litt., Diskus 2003), but it may have been overlooked in Poland. In the northern part of its range usually in warm places, isolated oaks or forest margins; in the south one of the commonest species. No positive records from Albania, Belarus, Bosnia, Finland, Norway, Latvia, Moldova, Poland or Russia. New (or confirmed) records from Bulgaria, Georgia, Italy: Sicily, Macedonia, Portugal, Turkey and Yugoslavia. Records from Estonia (Jürivete et al. 2000) should be checked, if they are based on Petersen (1930), they are wrong. The latter author illustrated male ruficapitella under this name. Occurs also as the only oak feeding species commonly on Madeira, most likely an introduced insect (Aguiar & Karsholt in press). Highest altitude: 2400 m in Turkey.
Life-history. Bivoltine with larvae in June-July, September-November, and adults from May to early October.
This taxonomic description is based on Van Nieukerken (2003).