Status and Distribution
Local, occasionally locally common, in southern and eastern England, the Midlands and south-east and eastern Wales. Very local in south-west England and the Channel Islands, rare in Yorkshire and Durham. Apparently absent from much of northern England, western and northern Wales, Scotland, Northern Ireland and Ireland.
Prior to 1982, records of this species may have been listed under S. cinctella from which it requires dissection, unless bred from Lotus pedunculatus (greater bird's-foot-trefoil).
Bradley & Fletcher no:
Maps updated with all data received by February 2018.
Finding the Moth
Larva: found between spun leaves and shoots from April to June. Syncopacma taeniolella will, on rare occasions, also use Lotus pedunculatus.
Adult: can be swept from the foodplant, disturbed during the afternoon and will come readily to light.
There are six Syncopacma species that have the dark forewing and, to some extent or other, a whitish fascia - many are scarce and have very restricted distributions. The size of the moth together with the habitat and available larval foodplants will help to narrow down the options to some extent. Breeding to establish the association with a particular foodplant is useful and could add additional information on the range of foodplants utilised by some of this genus. There is some overlap in foodplant usage and if in doubt, bred specimens should also be dissected.
It has been suggested that the presence or absence of a curve to the white crossband can assist in identification of these species. This is not the case, as although S. larseniella normally has a straight line, both S. taeniolella and S. cinctella can have a straight or slightly inwardly curved fascia. This feature is therefore unsuitable on its own as an identification feature.
S. taeniolella has a whitish fascia on the forewing underside, with a whitish spot or broken line on the underside of the hindwing, features not present in other members of this genus. See photographs of S. taeniolella and S. larseniella forewing and hindwing undersides in 'Images' of the respective species.
As S. larseniella will sometimes utilise common bird's-foot-trefoil, any Syncopacma spp. bred from common bird's-foot-trefoil without the white underside marking mentioned under S. taeniolella will require dissection to get to species level.
S. cinctella is the species most likely to cause confusion as it is very similar externally to S. larseniella. A lack of critical examination of specimens nationally in the past and to some extent more recently has made it difficult to accurately assess the true distribution of these two species. Although S. cinctella is believed to be much more local and may well sometimes be associated with a different habitat, it is advised that habitat differences should not be used in isolation when making an identification until familiarity with the species present at a site has been ascertained by dissection and/or breeding.
Structurally, S. cinctella has a relatively narrow forewing which appears broader towards the end, whereas S. larseniella does not appear to be broader at the end. The pale fascia on the upperside of the forewing (if present) is sometimes slightly inwardly curved in S. cinctella but can sometimes be straight as in most S. larseniella althgough this is difficult to judge in a live moth. For the time being it appears safe to say that if the moth is bred from greater bird's-foot-trefoil (so that S. taeniolella can be excluded) then it will be S. larseniella.
Single brooded from June to early August.