Vive la différence: an Anjou moth trap

Four-spotted Tyta luctuosa - Anjou, France

France is our favourite holiday destination. An easy hop over the Channel from Dorset opens up a heady mix of superb food and wine, pastoral landscapes and fascinating places to explore. There's only one snag: of necessity, most of our recent trips have taken place during the summer school holidays - a time that's generally poor for seeing wildlife. And this year (August 2026) is no exception, with temperatures down here in the Loire Valley currently peaking at a toasty 39 degrees. Animal life is generally keeping its head down, and even the butterfly numbers seem low.

But there are still moths! For a UK-based recorder, France is an exciting place to run a trap. And the further south you travel, the better it becomes. Moths that are familiar from home turn up next to species that would be major rarities on the British side of the Channel, as well as ones that have yet to make it to our shores.

For the record, I should add that I am staying in a rental cottage (gîte) in a small village around 10km north-west of Angers (Maine-et-Loire - the historic Anjou region). Being unsure of how well-separated the garden would be from its neighbours, I arrived with my low wattage (6W) battery-powered Heath-style trap. To date, I have run it on two nights, which have produced a total of 67 species and 314 individual moths - reasonable numbers for a trap of this power and type. In this post I'm just going to run through some of the highlights. 

Moth trap ready for opening.

The sight of a Portland Ribbon Wave (below) on the outside of the trap is always a hopeful sign. This species is regular in my Dorset garden, although never common; now resident in the UK, it is largely restricted to the south coast of England, but spreading north. But in France it's pretty common: there were a total of 20 in my two traps here. Portland Ribbon Wave is double-brooded in France (there's only a single brood in England), its caterpillars feeding on plants such as Yarrow.

Portland Ribbon Wave Idaea degeneraria - Anjou, France 

Another locally common species here that would cause surprise - and perhaps alarm - in the UK is Oak Processionary Moth (below). There were 15 in my two traps. In Britain, Oak Processionary is both a rare immigrant, although numbers are on the rise, and a resident that was accidentally introduced. It is a major pest of broadleaved woodland; while oak is its preferred larval food plant, it can spread onto other species during large infestations. This caterpillars are best avoided, as contact can cause skin and eye irritations; this isn't something that I've experienced personally, but if it's anything like my Brown-tail larval encounter some years ago then it will not be pleasant.

Oak Processionary Moth Thaumetopoea processionea - Anjou, France

Sitting nearby was a Pale Shoulder (below), one of five in my two traps. This exceptionally smart noctuid is a rare migrant to British shores; it has yet to make it my garden, but I live in hope. While there is some evidence that it has bred in England, there is no record of successful overwintering. Even in France the species has a generally southern distribution, being considered a migrant in the north of the country. It is also an impressive bird poo mimic.

Pale Shoulder Acontia lucida - Anjou, France

Inspecting the trap more closely, I could hardly miss a massive crambid sitting on the rain shield - a Giant Grass-moth Ancylolomia tentaculella (below). I knew straight away that it was a new species for me, which was a bit baffling as I have trapped in France before and it was not something that you would easily miss. But such is the joy of moth trapping: you never quite know what's going to turn up. Sorting out the identification was a bit of a challenge, as my standard French reference (Robineau, 2011) only covers macro-moths. It needed some searching of the web (as always, there are some great images on Lepiforum), which revealed that this is a species where males and females differ in both appearance and size - a good example of sexual dimorphism, although not as extreme as those species (such as Winter Moth) where females are wingless. Anyway, here are the female and male:

Giant Grass-moth Ancylolomia tentaculella (female) - Anjou, France

Giant Grass-moth Ancylolomia tentaculella (male) - Anjou, France

The size difference is not really apparent from these photos: for reference, the respective wing lengths are around 12-15 mm for the males and 15-20mm for the females. There are only a few British records of the species, but here it was the commonest 'micro' moth with 23 in the two traps combined.

I've already teased my star species of the night with the opening photo of this post - my first ever Four-spotted (also pictured below). Although this is resident in Britain, it is nationally scarce, with a patchy distribution that includes Dorset (notably Portland) and scattered sites through southern and eastern England. The larval foodplant is Field Bindweed Convolvulus arvensis.

A quick word about its common name: while only two (or at best three) white spots are obvious when the moth is at rest, all becomes clear when the wings are open, the white hindwing band giving the impression of two more spots (below).

Four-spotted Tyta luctuosa - Anjou, France

I encountered one nectaring the following day in the gardens of Angers Castle (which is well worth a visit); I hadn't realised that this moth also flies during the day.

  

Another day and night-flier only turned up in my second trap of the holiday: the stunning Spotted Sulphur (below), one of three. Formerly resident in East Anglia, this is now considered extinct in Britain. If it is a migrant species, it is a staggeringly rare one: the last British record seems to have been in the 1960s. Like Four-spotted, its larvae feed on Field Bindweed; the absence of both species from the British Isles may well be as a result of agricultural intensification, although other factors could have come into play. It would certainly be nice to see it again on our side of the Channel.

Spotted Sulphur Acontia trabealis - Anjou, France

The balance of species in a French moth trap can often be very different from that at home. Several groups were completely absent from the two traps that I have run down here, for example hawk-moths, tiger moths and footmen. This may be an artefact of the type of trap that I'm using, or they just may not be around this part of Anjou at the moment. Or it could be linked with the heat wave that we are experiencing here. 

In fact, the three most common species that I recorded were all noctuids. Coming in at second and third respectively were Vine's Rustic and Heart and Dart, both of which would be equally as common back in Dorset in mid-August. But at the top of the list was another French speciality - Great Dart (below).

 

Great Dart Agrotis bigramma - Anjou, France

Great Dart is a bit of a whopper as noctuids go, with a wing length of around 20mm. The size separates it from most broadly similar species, with Turnip Moth (which turned up here as well) being the main potential confusion. One of the key differences is that Great Dart has two sets of pale cross-lines with dark edges. In Britain, Great Dart is considered a scarce and infrequent migrant, but you only have to cross over to Normandy (or indeed the Channel Islands) to find it appearing as a frequent moth trap visitor.
 

The next noctuid (below) was a bit of a puzzle, and set me off looking for new species before I realised that it's actually a different form of a familiar August arrival at home - Centre-barred Sallow. The patten gives it away, with that distinctive central cross-line that could almost have been drawn by a ruler. In the British Isles this usually has a dark purple central band set against a yellowish background. However other forms are equally common on the continent including this all-brown form unicolor. 

Centre-barred Sallow Atethmia centrago (f. unicolor) - Anjou, France

While some groups of moths were missing, others seemed if anything to be over-represented - particularly the pyralid family (Pyralidae). I'm always pleased to see the lovely Rosy Knot-horn (below) - aka the Rhubarb and Custard moth; while this turns up most years in my Dorset trap, it would be unusual if it was missing from a summer moth trap in France.

Rosy Knot-horn Oncocera semirubella - Anjou, France.

Its close relative the Tufted Knot-horn (below) is a migrant to British shores, although it may now have taken root as a colonist. It's certainly more common down here in central France, with three in my second trap. The tufts of raised scales near the thorax separate it from similar species: this is quite a tricky group to identify.  

Tufted Knot-horn Acrobasis tumidana - Anjou, France

And to finish off with something completely different, I'll leave you with one of the other interesting invertebrates that also found its way into the trap - this Chestnut Weevil (below) with its impressive rostrum (projecting snout). The species occurs across western Europe, where it is a serious pest of Sweet Chestnut trees. According to GBIF there are no British records. The 'by-catch' from overseas moth traps is often as interesting as the moths themselves (heresy!), and I have a few more species to sort out from my Anjou adventure. But those will have to wait.
 

Chestnut Weevil Curcilio elaphas - Anjou, France

References

Robineau, Roland (2011) Guide des papillons nocturnes de France. Paris: Delachaux et Niestlé.

Sterling, Phil and Parsons, Mark (2023) Field Guide to the Micro-moths of Great Britain and Ireland. 2nd ed. London: Bloomsbury.

Waring, Paul and Townsend, Martin (2017) Field Guide to the Moths of Great Britain and Ireland. 3rd ed. London: Bloomsbury.

Websites

Atropos - migrant moth totals

GBIF - species distributions

Lepiforum