151 Carpatolechia proximella

GELECHIIDAE | Gelechiinae | Litini

35.151 Carpatolechia proximella (Spotted Birch Grey)

ws: 13-16mm; May-Jun; birch (Betula spp), alder (Alnus glutinosa); common throughout GB

Carpatolechia proximella §1 male

ID: From the key to British Carpatolechia species, this is identified by: absence of black bar at base of costa (excludes C.decorella); absence of dark streak on fold, absence of raised scales dorsal to fold and not heavily suffused fuscous (excludes C.fugitivella); labial palps not clear white (excludes C.alburnella). This leaves C.notatella/proximella and I find the features given in MBGBI4.2 for separating these two on external characteristics to be unconvincing and unreliable:
Fw with black spot dorsal to 2nd discal stigma + Labial palp S2 white with outer side spotted fuscous at base centre and apex C.proximella
Fw variable may be heavily suffused fuscous + Labial palp S2 greyish-white with 2 fuscous bands C.notatella
Male genitalia: The genus is identified from: S8 of separate dorsal and ventral plates; gnathos absent; uncus pointed; digitate lobes on juxta.
It is possible that C.proximella can be identified from the shape of the dorsal plate on S8 but I do not have any comparative material and this is the only species for which the plates are shown at dissection group.
The male genitalia show distinctive differences in relative lengths of the valvae and the digitate lobes on the juxta:
C.proximella - digitate lobes ~1/2 length of valvae; digitate lobes narrow towards a rounded apex and meet at base to form a distinct 'V'-shape.
C.notatella - digitate lobes ~3/4 length of valvae; digitate lobes of ~even width; uncus with a nipple at apex
C.decorella - digitate lobes ~1/2 length of valvae; digitate lobes narrow towards a finely pointed apex and meet at base to form "V"-shape.
C.alburnella - digitate lobes longer than valvae
C.fugitivella - digitate lobes ~1/2 length of valvae; valvae very long, reaching almost to apex of uncus (with the uncus extended), uncus somewhat rounded.

Variation
Dissection
Male genitalia
Female genitalia

§1 Strumpshaw Fen, Norfolk; 28/05/2012; male; fw 6.3mm
§2 Glen Urquart, Inverness-shire; 15/07/2012; male
§3 Upton Fen, Norfolk; 10/05/2014; male; fw 7.9mm
§4 Winterton, Norfolk; 11/06/2015
§5 Winterton, Norfolk; 11/06/2015
§6 Winterton, Norfolk; 11/06/2015
§7 Strumpshaw Fen, Norfolk; 06/06/2016; male; fw 6.6mm
§8 Loch Rannoch, Perthshire; 16/06/2021; female; fw 7.5mm; to light
§9 Cliburn Moss, Cumbria; 15/05/2024; male; fw 8.1mm
All images © Chris Lewis