What Is a Micromoth?
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A huge amount of work has gone into collecting Macro-moths records, particularly in the last few years, to achieve the maximum coverage possible for the forthcoming Atlas of Larger Moths. While County and Vice County Moth Recorders (CMRs) are still very busy preparing and sending the macro- moth data to Butterfly Conservation, the rest of us are beginning to wonder what to concentrate on next. Although the recording of larger moths will continue, the passing of the Atlas deadline has definitely left a bit of a void waiting to be filled. And what better way to plug that gap than to take on the Microlepidoptera? Many of you will already have dabbled, or even dived with enthusiasm into this large but often bewildering group of insects. With well over 1500 resident or regular migrant smaller moths in Britain (compared to around 900 macro-moth and 83 Butterfly species) this certainly presents an interesting challenge, but it just so happens that help is at hand. With perfect timing the National Moth Recording Scheme (NMRS) has been expanded to include all validated micro-moth records. The primary aim of this newsletter is to introduce moth recorders to the Micro-moth side of the NMRS and its new National Verification Guidelines and Grades. It is also designed to explain the verification processes that will be applied to your micro-moth records at a county and at a national level. To start the ball rolling, a general introduction to the micro-moths and their recording in Cheshire, Cumbria & Lancashire has been provided and it is hoped this will answer most of the questions you have about this exciting new project. WHAT IS A MICROMOTH? This sounds a simple question but, surprisingly, there is not a simple answer. You’d think it relates to those really tiny ones that are often passed over as too difficult to identify. Well, I suppose, yes it does to some extent, but the micros are much more variable and diverse than that. For instance, if you have found and recorded Anania hortulata (the small magpie moth), then you’ve already made a micro-moth record! Anania hortulata small magpie moth (Photo: Ben Smart) 1 A quick look through the new Agassiz, Beavan and Heckford checklist (AB&H – see below) doesn’t resolve things either. Between the first and last listed micromoths in AB&H you will find the Swift moths, the Burnets, the Clearwings, moths such as the Goat Moth and the biggest surprise of all – the Butterflies. We, of course, warmly welcome those many butterfly recorders to the micro-moth recorders club! Gatekeeper - an honorary micromoth? (Photo Ben Smart) But, of course, this isn’t the whole story. In AB&H, as was the case in its forerunner, the Bradley list, Lepidoptera are listed in Taxonomic Order (an order running from the most primitive to the most developed). They start with what might best be described as fully paid up, card- carrying members of the micro-moth club – Micropterix (such as M. aureatella), Eriocrania, Enteucha and Stigmella; Britain’s smallest moth (Enteucha acetosae) being amongst them. The Swift moths, and a few other larger species, are also listed here amongst our most primitive species. At the opposite end of this list of micro- Micropterix aureatella moths are the Crambidae, which includes the familiar (Photo: Ben Smart) grass moth Agriphila straminella and some more ‘macro- moths’ and the butterflies slotted in-between. So ‘Micro-moths’ don’t fit neatly into any taxonomic category. They are purely a human attempt to categorise a group of moths by size rather than taxonomically, which inevitably results in anomalies. How many of us have looked at Pleuroptya ruralis (mother of pearl) and become frustrated that it can’t be found in our macro-moth books? This large species looks completely out of place as a micro. As a rule you are usually safe in considering anything smaller than Agriphila straminella Idaea seriata (small dusty wave), for example, to be a micro (apart, (Photo: Ben Smart) of course, from the mother of pearl and related species). CONFUSING MICROS AND MACROS As mentioned above with the mother of pearl, there are some micros that might be confused with macro-moths. One that often caught new recorders out in the pre-internet days was Tortrix viridana (green oak tortrix) which was not infrequently recorded as Earias clorana (cream-bordered green pea). This doesn’t seem to happen nearly so much these days as common micro-moths become more widely known. 2 Strangely it is more often that the problem occurs the other way around. A few of our larger moths can be mistaken for micros. Prominent amongst these is Nycteola reveyana (oak nycteoline) which resembles an Acleris species or other similar Tortricid moths with its distinctive bell-shape when at rest. Another potential confusion area is the small Snout moths. Schrankia costaestrigalis (the pinion- streaked snout) is often confused with members of the Pyralidae or Crambidae. Despite these minor problems, increased familiarity with the full range of micro-moths will help both your micro- and macro-moth identification skills. WHAT DO I NEED TO STUDY MICRO-MOTHS? There are a wide variety of County and National websites that contain a wealth of information but the first and best step is to obtain a copy of a good field guide. Sterling, Parsons and Lewington, a Field Guide to the Micro-moths of Great Britain and Ireland is an excellent place to start and I suspect many of you will already have a copy. This book, with its family identification key, drawings of moths in their natural resting position, informative text and generalised distribution maps has everything a beginner and more experienced recorder needs. Not all species are shown but it is an excellent starting point. I’d also thoroughly recommend the Second Edition of Chris Manley’s, British Moths - photographic guide to the moths of Britain and Ireland. If you want to avoid getting too swamped early on, then try the Common Micro-moths of Berkshire. Many of the species in this guide are also found in Cheshire, Cumbria and Lancashire while the text, with accompanying photos, has excellent pointers and tips on what to look for when trying to identify these commonly encountered moths. See the end of this Newsletter for more details of this and the other books mentioned above. Small glass tubes (see photo) are essential for the study of micros as the larger plastic ones do not allow easy examination of the smaller species. A 10x hand lens is another ‘must-have’ to allow close examination of a moth’s forewing markings and external structures such as antennae and palps, all of which aid identification. A net can be handy on occasions. It may surprise some that a moth trap is not listed here. Although they add considerably to the number of micromoths recorded, so much more can be learnt from daylight-hours fieldwork. It is therefore an additional tool in recording the smaller moths rather than the main one. WHERE DO I FIND THEM? Micro-moths or their larvae can be found in almost all habitats, including in plants under water, but where better to start than by having a look in or around your house. Even if the garden is small with 3 few if any plants there will be micros around. Some come into houses to rest, overwinter, or even spend their whole life cycle. Keep your eyes open for that small dark mark on the wall or ceiling in a corner of a cool room - it might be a moth (if not it’s time to redecorate!) or look for dead ones on window sills. Have a wander around outside looking for larval feeding signs or, as spring approaches, tap a few plants or shrubs to see what appears. Always have a little pot handy! Within no time, you’ll have recorded Endrosis sarcitrella (white-shouldered house moth), Hoffmanophila pseudospretella (brown house moth) or a Mompha species or two overwintering in the house or shed. In the garden around a wood pile Nemapogon cloacella (cork moth) or Esperia sulphurella will fly at dusk and out of the plants there will be a good chance that you’ll disturb Epiphyas postvittana (light-brown apple-moth). Esperia sulphurella (Photo: Ben Smart) If you have a conifer hedge you’ll without doubt add a couple more species by tapping the leaves to watch the tiny Argyresthia trifasciata or even smaller Argyresthia cupressella fly out in the summer months. On the popular garden shrub, Pyracantha, you are bound to find the feeding signs of the pyracantha (or firethorn) leaf-miner. A search on UK Moths http://ukmoths.org.uk/ under Phyllonorycter Argyresthia cupressella leucographella will show you what to look for. (Photo: Ben Smart) Further afield – well, what a huge range and diversity of insects await you at any time of year in all habitats. You’ll need to get used to the idea that there is no closed-season for moths. If you put your moth trap away in the autumn and bemoan those long cold winter nights and a late arriving Spring, think again. Larvae are out there with readily identifiable feeding signs, seed heads can be collected for a bumper emergence of exciting insects in spring, moths can be found hibernating and even on the coldest and most unfriendly of February days, larval spinnings might be found in lawn or wall mosses. Just imagine the thrill of looking at a pristine, newly-emerged micro that you, on your very own, have managed to find and breed through from the larval stage.