Identification pages

This page will contain some resources and links on identifying some of the trickier species. It's currently in the early stages of development so there isn't much here yet! But we will add further resources when we can.

General

This document lists some of the species that are frequently recorded in error in Berkshire, and highlights some of the difficult' species that either need to be dissected, or recorded as aggregates:

• Verifying moth records in Berkshire

See also:

• Townsend, M.C., Clifton, J., and Goodey, B. 2010. British and Irish moths: an illustrated guide to selected difficult species. Butterfly Conservation, online version.

Macro-moths

Five-spot and Narrow-bordered Five-Spot Burnets (Zygaena trifolii and Z. lonicerae)

These two species are very similar and individual moths may be impossible to distinguish. Where a colony exists a judgment can be made from looking at the range of variation in the spots and whether they are merged, see the Difficult Species guide for more information. The true Five-spot Burnet was until recently a rarity in the county but is being increasingly found on chalk download sites in the west of Berkshire. Appearance, flight period, habitat and potential foodplants can all provide clues, and both eggs and larvae have some differences that can add further evidence, but in isolation it is hard to make judgments over individual moths.

If in any doubt please record as the aggregate Zygaena lonicerae/trifolii. Please avoid using subspecies names for Narrow-bordered Five-spot Burnet if you can (always use Zygaena lonicerae, not Zygaena lonicerae lonicerae or any of the other subspecies). It may be valid to distinguish subspecies for the true Five-spot Burnet, which is considered to be subspecies Zygaena trifolii decreta in wetland habitats and Zygaena trifolii decreta in dry grasslands. However, there is some evidence that these habitat-based distinctions are breaking down as the species spreads. If you are sure you have true Five-spot Burnet it can be linked to just the species name, Zygaena trifolii, unless you have evidence to suggest one or other subspecies.

True Five-spot Burnet remains the less common of the two species in Berkshire, and it is helpful if you add a comment to any records to explain what led you to identify as that species.

Peacock and Sharp-angled Peacock moths (Macaria notata and M. alternata)

These two can be difficult to tell apart, especially if the moths are at all worn. For info on distinguishing them see Chris Lewis' comparison page and the Difficult Species guide.  A photo or specimen is preferred to back up the records, and if there is any doubt (e.g. for worn individuals) please either don't record them, or record just as genus Macaria. In Berkshire Peacock is most frequently seen in the east of the county and Sharp-angled Peacock in the west, but there is plenty of overlap so these two always need to be checked carefully.

Langmaid's and Lesser Broad-bordered Yellow Underwings (Noctua janthina and N. janthe)

Langmaid's Yellow Underwing was first recorded in Berkshire in 2020, and in subsequent years has started to be seen more frequently. To distinguish Langmaid's Yellow Underwing it is essential to examine the upperside of the hindwing (including the costa of the hindwing, which is hidden under the forewing unless the wings are fully extended) and the underside of the forewing, again fully extended to show the markings. The specimen below was caught by Finley Hutchinson in Reading on 30 July 2022.