| | Insects of Britain and Ireland: the genus Phyllonorycter (Lepidoptera-Gracillariidae) |
Associated with trees. On Betulaceae; Betula spp..
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 the middle pair less well developed.
Adults. Antennae white to the base (lightly ringed greyish). Face white. Head white and fuscous. Thorax shining golden brown; with a conspicuous median pale streak. Wing-span 8–10 mm. Forewings clear golden ochreous; not clear shining white; with a well defined basal streak (this narrow, traversing about a third of the wing). The basal streak pale; straight, neither markedly long and slender nor sinuate; not dark-edged above. Forewings with well defined pale strigulae (white). Costal strigulae 4. The first costal strigula not basipetally extended along the costa. Dorsal strigulae 3. Forewings with the first costal strigula approaching a dorsal one at an acute angle; with one transverse pale fascia (via confluence of the first pair of strigulae), or without transverse pale fasciae. The fascia (or the interrupted fascia) angulated. Forewings with conspicuous dark apical marking. Forewing apical marking comprising a dark apical strigula surmounted by a white spot. The forewing fringe narrowly dark-lined along the bases of the cilia. The forewing basal fringe line complete, or interrupted (by the third dorsal strigula). Hindwing cilia light fuscous (slightly golden).
The left and right male genital valvae very similar in size and form (triangular-elongate). The left male genital valva not spine-tipped. The left and right male genital valvae without free costae. The aedeagus long and relatively slender with a triangular barb towards the apex. The female genitalia exhibiting a signum on the bursa copulatrix (pointed at either end).
Adults abroad May and August.
Illustrations. • Phyllonorycter cavella: Jacobs (1945). • Phyllonorycter species on Birch. 1, Phyllonorycter (Lithocolletis) cavella; 2, P. ulmifoliella; 3, P. anderidae; 4, P. corylifoliella. • Phyllonorycter cavella, genitalia, 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’.
