| | Insects of Britain and Ireland: the genus Phyllonorycter (Lepidoptera-Gracillariidae) |
Synonym: Phyllonorycter alnifoliella (Hübner)
Associated with trees. On Betulaceae; Alnus (not confined to Grey Alder, Alnus incana, as distinct from P. strigulatella).
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 mixed white and fuscous. Thorax dark fuscous, or white, or white and fuscous. Wing-span 7–9 mm. Forewings variable, dark ochreous, or brown, or fuscous; not clear shining white; with a well defined basal streak (this somewhat lanceolate with its costal edge arched towards the costa, reaching to the middle of the wing). The basal streak pale; dark-edged above. Forewings with well defined pale strigulae (white). Costal strigulae 4. Dorsal strigulae 3. Forewings with the first costal strigula approaching a dorsal one at an acute angle; without transverse pale fasciae. 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 (with an ill defined dark 'hook'); narrowly dark-lined along the bases of the cilia. The forewing basal fringe line interrupted (by the third dorsal strigula). Hindwing cilia brownish fuscous.
The left and right male genital valvae similar in size and form (broadly oblong). The left male genital valva not spine-tipped. The left and right male genital valvae having free costae. The left and right free costae completely detached from the valvae to arising near the bases of the valvae; similar (almost as long as their valvae, including the long spine-tips).
Adults abroad May and August.
General comments. Recognised as distinct in Bradley's (2000) check list, but much confused with P. strigulatella (q.v.) and the mainland-European P. alnifoliella, which formerly included both of them. Diagnostic descriptions have proved elusive, and the present description only dubiously between these species morphologically. Genitalia: Gustafsson (2007): http://www2.nrm.se/en/svenska_fjarilar/svenska_fjarilar.html#DV.
Illustrations. • Phyllonorycter rajella (as P. alnifoliella): Jacobs (1945). • Pyllonorycter rajella: Ian Kimber (2018), UKmoths https://ukmoths.org.uk/. • Pyllonorycter rajella, mine in Alnus: Ian Kimber (2018), UKmoths https://ukmoths.org.uk/. • P. stettinensis, P. schreberella and P. cf. rajella (as alnifolia): Stainton (1855) Plate V, under Lithocolletis. PHYLLONORYCTER. 1, P. stettinensis: imago (1m), larva (1a), and alder leaf with two mines (1b). 2, P. schreberella: imago (2m), larva (2a) and mined elm leaf (2b). 3, cf. P. rajella: imago (3m), larva (3a), and mined alder leaf (3b). • Stainton (1855), Plate V: original legend.. • P. rajella (as alnifoliella Hübner) and 5 other species: Hübner, 1796–1819.
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’.
