Category: Science

TL:DR – One can attract clearwing moths to one’s garden with focused planting or with synthetic pheromones.

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There is a beautiful group of moths known as clearwings that at first glance look rather waspish. Rather than having wings covered in scales like all of the other Lepidoptera (which roughly translates as scaly wings, or perhaps more strictly tiled wings), their wings a transparent, but for the supportive struts.

These are generally day-flying moths and look like tiny shimmering jewels if you catch sight of one. The males are attracted to sex pheromones exuded by the female. As such, it is possible to draw them to a lure impregnated with the appropriate sex pheromone for each species. The moths that arrive at the lure can then be counted and ticked, perhaps even photographed in the name of (citizen) science.

I purchased a set of pheromone lures from Anglian Lepidopterist Supplies ( a company that does exactly what it says in its name). I had previously used a lure for the Emperor moth with great success regular readers will recall. In the clearwing set there are lures for ten clearwing moth species. I began putting lures out individually on likely days – warm and breezy – back in May, but it is only into June that I’ve had success with the clearwings.

In early June, a Red-belted Clearwing was drawn to the target lure. By mid-June I was trying others and discovered that the lure for a different species, the Large Red-belted Clearwing drew in the smaller cousin – 14 of them, in fact! I put the lure out for the Hornet Moth next, no luck. Then, the  Currant Clearwing, success this time. Then I tried the Orange-tipped Clearwing lure, and drew in not the target species but a Yellow-legged Clearwing. Later, I learned from an expert name of Anthony Wren, that those two lures are identical in composition and now I am musing on what that says about the evolutionary history of these two species.

Clearly, the lures are not 100% on point when it comes to the species they attract. Now, ALS does list non-target species for each of its lures, so it is not entirely surprising. The reason is perhaps to do with the composition of the lures.

As I understand it, the lures each have the primary sex pheromone of the target female, but they also contain a mixture of other modified, volatile fatty acids and so on. This will lead to a degree of overlap in what the lure attracts because those other chemicals may well be interesting to other species of insect. It may not be about sexual attraction it could simply be that they are attractive or stimulating molecules. There does not seem to be a whole lot of clarity in the overall picture of what does what to each species yet, although there is a huge amount of excellent and ongoing research in this area.

 

Orange-tailed Clearwing (Synanthedon andrenaeformis) with its golden hair pencil turned up (2 or 3) at about 10am to the SYN lure in the garden on 16th June 2021.

Earlier in the year, I bought myself a summer of moths – a pack of pheromone lures with which to entice clearwing moths into the garden, with a view to grabbing a quick photo opportunity and letting them on their way to find a mate etc.

Regular readers will recall I have mentioned pheromone lures before in the context of the Emperor moth. The clearwings are a very different group and I’ve not had time to find out much detail about the chemistry of their pheromone attactants. Regardless, I have been putting out a lure, known as “myo” for the Red-belted Clearwing (,em>Synanthedon myopaeformis).

Usually, I hang the lure in the back garden and have had no luck, but on a whim, today I put it in the front garden and within about ten minutes, a RbCw turned up. The specimen was a lot smaller than I was anticipating, but checking in my “Collins”, I see that it is a rather small moth, with a wingspan of 19-24 mm. I’d say this one was on the lower end of that size scale. Beautiful creature, obviously belted and see-through wings. If you didn’t know, you might guess at it being some kind of wasp-type insect. But, definitely no sting in the tail of this one.

The species flies June to August but is rarely seen except by those with a pheromone lure for citizen science purposes. The larvae live under the bark of old apple, and other fruit trees such as pear and almond. Got the best snaps I could of this rather skittish specimen so I could let him back into the wild sooner, rather than later.

This tiny little micro moth known as Aethes tesserana is a mere 5 millimetres long. It was drawn to a 40W actinic lamp in our garden on Sunday evening (2021-06-06). It was a still and balmy evening, I seem to remember.

Incidentally, not all the micro moths are tiny, some of them are bigger than the macro moths, some of them are huge. The distinction between micro and macro is now understood to be about evolutionary history rather than size. All the butterflies sit in the micro moth grouping, being just a specific group within the moth family.

A. tesserana does have a trivial, vernacular name, it’s sometimes called the Downland Conch, and is listed as such on iRecord. However, these vernacular names are rarely official when it comes to the micro moths and indeed are frowned upon in many cases by moth-ers and lepidopterists because they are inconsistent and the scientific binomials are preferred to avoid ambiguity.

Meanwhile, some long-form reading matter for you (a book, in other words) – Much Ado About Mothing.

For a lot of people, moths are tiny, fluttery creatures that turn to dust if you try to catch them and whose caterpillars can chew through their vegetable patch, their prize perennials, and even their carpets and clothes. Now, there are pest species, admittedly, and these can to some extent be controlled in appropriate conditions. However, for those who have been initiated into the wonders of the Lepidoptera, the 180,000 different species around the world are a natural wonder to behold.

For those of us who do get hooked on moths – we call ourselves “moth-ers” by the way – it can become an obsession that persists from the first very first lep sighting. For those who insist that moths and butterflies are somehow different, and that butterflies are far more beautiful and far more worthy of our attention, it’s worth pointing out that all butterflies are just a single group within the Lepidoptera.

The other groups include the noctuids (also known as owlets), the geometers (their caterpillars, larvae, measure the earth, they’re the inchworms), the sphinx moths (also known in the British Isles as the hawk-moths), and several others. Butterflies are merely one such group among the moths. Moreover, they’re actually just one group within the so-called “micro moths” (nothing to do with size, everything to do with their place on the evolutionary tree).

It’s complicated, and all moth-ers come to the obsession through a different route. In his wonderful new book, Much Ado About Mothing, James Lowen, challenges all those dusty preconceptions about moths. He takes us on a lavish and circuitous route around the UK searching for the rarest and most intriguing of our scaly-winged insects. Incidentally, of the 180000 worldwide species a mere 2500 or so are found in the UK, some of them migrants and rare visitors.

With Lowen, we clamber up mountains, we wade through marshes, and we look for what lurks in the wood and on the trees in ancient woodland. What we find is an incredibly diverse group of animals, all of them sharing common features but each very different from the next. Lowen shows us just what most people seem to miss about moths – their natural beauty.

Mothing, as a hobby, is on the rise. It has often been a parallel hobby for birders, one that can be done with lures and lighttrap or even just a white sheet and a bright torch, in one’s own back garden or a local patch of countryside, and…even right in the centre of the city! Your mileage may vary on what you find, but each mothing experience brings new delights, and a new hope that the next lep to turn up will be one of the rarest of the rare or perhaps even one once thought extinct that turns out to be very much extant.

If you are not yet convinced, then delve into Lowen’s book, it will astonish and intrigue even the hardiest of mottephobe, I am sure. And, remember butterflies are just one group within the moth family…and who doesn’t like butterflies?

If you love or loathe lepidoptera buy this book, Lowen’s wonderful enthusiasm will give you a mental boost either way and if you were indifferent to the scaly-winged insects, it might even let an interest pupate and to take to the air.