| | Insects of Britain and Ireland: the genus Phyllonorycter (Lepidoptera-Gracillariidae) |
Synonym: Phyllonorycter tenella (Zeller)
Associated with trees. On Carpinaceae; Carpinus.
Larvae. The larvae mining in leaves; in the under-side. Found in July, or September to October. The larva pupating in a morphologically distinct cocoon.
Pupa. The pupal cremaster with two pairs of hooked processes; two pairs of cremastal processes more or less equal in length; cremastal processes relatively short and basally broad (the outer pair stouter).
Adults. Face white. Head white. Thorax white; without a median pale streak. Wing-span 7–8 mm. Forewings shining white, or ochreous, or fuscous (or ochreous-fuscous: the usual interpretation of this wing as representing dark patterning on a shining white backgound seeming no better than viewing it as white markings on a dark background); clear shining white with coloured markings, or not clear shining white; with a well defined basal streak (this broad, reaching to or beyond the middle of the wing, joining the first dorsal strigula; or at least interpretable as such). The basal streak pale; straight, neither markedly long and slender nor sinuate; not dark-edged above. Forewings with well defined pale strigulae, or lacking well defined pale strigulae (depending on interpretation: the latter being the case if the wing is seen as white with dark strigulae and fasciae). Costal strigulae (if interpreted as such,) 4. Dorsal strigulae (if interpreted as such,) 2, or 3. Forewings with the first costal strigula approaching a dorsal one at an acute angle; with one transverse pale fascia (the first costal strigula joining the first dorsal one). The last fascia straight. Forewings with conspicuous dark apical marking. Forewing apical marking comprising a round blackish apical spot to comprising an elongate blackish apical spot. The forewing fringe traversed towards the apex by a narrow, curved dark line to not traversed by a dark line (this ill defined); narrowly dark-lined along the bases of the cilia and narrowly dark-lined along the tips of the apical cilia. The forewing basal fringe line more or less complete, or confined to the apical region or fading dorsally (stronger apically, fading dorsally). Hindwing cilia light fuscous. The left and right male genital valvae with entire bodies.
The left and right male genital valvae similar in size and form (broadly linear). The left male genital valva not spine-tipped (but tipped by a costal-marginal pair of short straight spines). The left and right male genital valvae having free costae. The left and right free costae arising near the bases of the valvae; similar (these quite long, apically bent into a fairly long spine-tip). The aedeagus long and relatively slender with a triangular barb towards the apex. The female genitalia exhibiting a signum on the bursa copulatrix (comprising two or more points).
Adults abroad May and August.
Illustrations. • Phyllonorycter tenerella (as P. tenella): Jacobs (1945). • Species on Hornbeam in Britain. 1, Phyllonorycter messaniella (more often of oak, beech or sweet chestnut); 2, P. tenerella; 3, P. quinnata. • Phyllonorycter tenerella (as tenella), genitalia: Pierce and Metcalfe (1935).
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. Insects of Britain and Ireland: the genus Phyllonorycter (Lepidoptera-Gracillariidae) Version: 14th April 2022. delta-intkey.com’.
