Surely a Five-Spot Burnet?
Well in fact it is a Narrow-Bordered Five-spot Burnet (Zygaena lonicerae). If you didn’t know you should not feel too bad, as many experts consider them to be almost indistinguishable from the regular Five-Spot Burnet (Zygaena trifolii) using a photo like this
Generally in the UK the Narrow-Bordered is the more abundant species although not recorded widely in Montgomeryshire. However with the help of Peter I have recently identified a colony in our field near Berriew so I expect we should be getting a lot of new records in the east of the county but the problem is how can you tell them apart? Well in the process of checking my specimens it appears that the forewing wing shape is consistently narrower (‘more pointed’) in the Narrow-bordered but I need to examine a lot more examples of both species from different sites to see if this difference is consistent and does not overlap between the species.
This is where I need your help.
If you find any five-spotted burnets while you are out and about in July (both species should be flying at this time), please could you take a photo like the one above where the camera is positioned as close as possible to perpendicular to the forewing. As always it may be easier to do if you catch them and give them some cooling off time in the fridge first. I would be particularly interested if you find any with merged or confluent spots and from damp areas where there is lots of Greater Birdsfoot Trefoil as these are almost certainly Z. trifolii. Similarly specimens from areas of rough, dry grassland with well separated third and fourth spots in the Eastern side of the county would be especially useful as these are most likely to be Z. lonicerae.
If you get any photos please send them to me at timwardhome@outlook.com with a brief description of where you found them. I’ll let you know my best guess at ID as soon as possible and if this is a consistent characteristic, I will share the data and give some tools to help you do your own ID.
Thanks for your Help
Tim