18.001 Plutella (Plutella) xylostella (Diamond-backed Moth)
ws: 12-17mm; bivoltine May, Jul-Sep; Brassica spp; common throughout GB
Plutella xylostella §3 male
ID: generally readily recognised by brown forewing with pale dorsal streak
Key (to Plutellidae): forewing narrow (length >3.25x width) (excludes Eidophasia messingiella); with pale dorsal streak (excludes Rhigognostis senilella); termen not contrastingly dark (excludes Plutella porrectella); forewing without pink suffusion (excludes Rhigognostis incarnatella); costa not conspicuously strigulate (excludes Rhigognostis annulatella); forewing without rows of spots (excludes Plutella haasi) > Plutella xylostella.
In some specimens the dorsal streak is obscured by brown scales, such specimens can be identified by the pattern of annulation of the porrect antennae, the very oblique termen and a short pale supercilium.
Key (to Plutellidae): forewing narrow (length >3.25x width) (excludes Eidophasia messingiella); with pale dorsal streak (excludes Rhigognostis senilella); termen not contrastingly dark (excludes Plutella porrectella); forewing without pink suffusion (excludes Rhigognostis incarnatella); costa not conspicuously strigulate (excludes Rhigognostis annulatella); forewing without rows of spots (excludes Plutella haasi) > Plutella xylostella.
In some specimens the dorsal streak is obscured by brown scales, such specimens can be identified by the pattern of annulation of the porrect antennae, the very oblique termen and a short pale supercilium.
§1 Foulness, Essex; 26/08/2007
§2 St Marys, Isles of Scilly; 24/10/2007
§3 Strumpshaw Fen, Norfolk; 18/09/2011; male; fw 8.0mm
§4 St Marys, Isles of Scilly; 02/10/2011; female
§5 Isle of Wight; 30/05/2014
§6 Westcliff-on-sea, Essex; 21/05/2018; male; fw 6.6mm
§7 Westcliff-on-sea, Essex; 21/05/2018; female; fw 7.6mm
§8 Loch Naver, Sutherland; 23/06/2021
§9 Bampton Grange, Cumbria; 07/04/2026
All images © Chris Lewis
§2 St Marys, Isles of Scilly; 24/10/2007
§3 Strumpshaw Fen, Norfolk; 18/09/2011; male; fw 8.0mm
§4 St Marys, Isles of Scilly; 02/10/2011; female
§5 Isle of Wight; 30/05/2014
§6 Westcliff-on-sea, Essex; 21/05/2018; male; fw 6.6mm
§7 Westcliff-on-sea, Essex; 21/05/2018; female; fw 7.6mm
§8 Loch Naver, Sutherland; 23/06/2021
§9 Bampton Grange, Cumbria; 07/04/2026
All images © Chris Lewis
Page published 30/01/2012 (§1-4) | §5 added 29/01/2015 | §6&7 added 07/03/2019 | §8 added 14/10/2021 |
§9 added and text amended 21/04/2026
§9 added and text amended 21/04/2026
