07.015 Nematopogon swammerdamella (Large Longhorn)
ws: 17-21mm; May-Jun; larva feeds on dead leaves; common in woodland throughout UK
Nematopogon swammerdamella §1 male
ID: Of the 5 British Nematopogon species only N.swammerdamella is compatable with the size of specimen §1, all other species being smaller
Key: Hindwing narrow scales widely distributed; fw pale ochreous (not greyish ochreous); ws 17-21mm > N.swammerdamella
The male hindwing has uniformly narrow scales, the female has broader scales at apex.
Male genitalia: Differences between Nematopogon species occur in the architecture of the apex of the valvae and in a comb of bristles on the valva. N.schwarziellus is readily identified by a small spine at the apex of the valva, this being absent in all other species. N.metaxella & pilella have a rounded apex to the valvae and in N.swammerdamella the apex comes to a point. N.schwarziellus and N.metaxella have a long comb of bristles along the ventral border of the valva terminating distally close to the apex of the valva. N.pillla and N.magna have a shorter comb of bristles on the internal surface of the valva (i.e. not on the margin). These two can be distinguished by the apex of the aedeagus which has a spine in N.magna but not in N.pilella. In N.schwarziellus there is an additional short comb of bristles near the base of the ventral edge of the valva. N.swammerdamella has three relatively short combs of bristles the most distal of which terminates some distance from the apex of the valva.
Key: Hindwing narrow scales widely distributed; fw pale ochreous (not greyish ochreous); ws 17-21mm > N.swammerdamella
The male hindwing has uniformly narrow scales, the female has broader scales at apex.
Male genitalia: Differences between Nematopogon species occur in the architecture of the apex of the valvae and in a comb of bristles on the valva. N.schwarziellus is readily identified by a small spine at the apex of the valva, this being absent in all other species. N.metaxella & pilella have a rounded apex to the valvae and in N.swammerdamella the apex comes to a point. N.schwarziellus and N.metaxella have a long comb of bristles along the ventral border of the valva terminating distally close to the apex of the valva. N.pillla and N.magna have a shorter comb of bristles on the internal surface of the valva (i.e. not on the margin). These two can be distinguished by the apex of the aedeagus which has a spine in N.magna but not in N.pilella. In N.schwarziellus there is an additional short comb of bristles near the base of the ventral edge of the valva. N.swammerdamella has three relatively short combs of bristles the most distal of which terminates some distance from the apex of the valva.
§1 Blean Woods, Kent; 21/04/2011; male; fw 10mm, antenna 17mm
§2 Isle of Wight; 05/06/2014; male; fw 8.9mm
§3 Fouldon Common, Norfolk; 15/05/2015; female; fw 9.2mm; netted by day
§4 Pound Wood, Essex; 01/05/2019; male; fw 8.8mm; to light
§5 Pound Wood, Essex; 25/04/2019; female; fw 8.7mm; netted by day
§6 Pound Wood, Essex; 09/05/2020; male; fw 10.1mm; to light
§7 Abernethy Forest, Inverness-shire; 24/05/2025; female; fw 8.9mm
All image © Chris Lewis
§2 Isle of Wight; 05/06/2014; male; fw 8.9mm
§3 Fouldon Common, Norfolk; 15/05/2015; female; fw 9.2mm; netted by day
§4 Pound Wood, Essex; 01/05/2019; male; fw 8.8mm; to light
§5 Pound Wood, Essex; 25/04/2019; female; fw 8.7mm; netted by day
§6 Pound Wood, Essex; 09/05/2020; male; fw 10.1mm; to light
§7 Abernethy Forest, Inverness-shire; 24/05/2025; female; fw 8.9mm
All image © Chris Lewis
Page published May 2011 (§1) | §2 added 26/12/2014 | §3 added 01/12/2015 | §4&5 added 06/01/2020 | §6 added 26/05/2021 |
§7 added 03/11/2025
§7 added 03/11/2025
