Butterfly Conservation: Highland Branch

Moths of the month: May

This is a monthly series illustrating several characteristic moths to look out for in our area. Text and photos by Roy Leverton.

You can also view the other months by selecting the links at the bottom of this page.


	The Streamer Anticlea derivata May (sometimes late April). Road verges, hedgerows; sometimes seen at lighted windows. Wild rose is the only foodplant of this delicately tinted moth. *Click on the image to enlarge it.*

	Brimstone Moth Opisthograptis luteolata May into July. Woodlands, gardens. This bright yellow moth can be seen flying at dusk near hawthorn and rowan. *Click on the image to enlarge it.*

	Scalloped Hazel Odontopera bidentata May and June. Woodlands, gardens. Recognised by its scalloped shape and hazel colouring. The caterpillar feeds on almost any tree or shrub. *Click on the image to enlarge it.*

	Common Heath Ematurga atomaria May and June, moorland. Found on any heather moor, flying in the sunshine. The male has very feathery antennae. *Click on the image to enlarge it.*

	Puss Moth Cerura vinula May and June, most habitats. Less often seen than its caterpillar, this large, fluffy moth is sometimes found at rest on sallows and aspen. *Click on the image to enlarge it.*

	Ruby Tiger, Phragmatobia fuliginosa borealis May into June. Heather moorland, coasts, other open habitats. Smaller and duller than its relatives, this tiger moth is less often seen than its hairy caterpillar, despite being mainly diurnal in the Highlands. *Click on the image to enlarge it.*

	Garden Carpet, Xanthorhoe fluctuata Late April to June, then again in August & September. Gardens, also coastal cliffs. This carpet moth is aptly named, being far commoner in urban gardens than in the open countryside. Its caterpillar feeds on various cultivated crucifers such as stocks and wallflower, also arable weeds in the same family. *Click on the image to enlarge it.*

	Pale Prominent, Pterostoma palpina May into June. Woodland, scrub and carr with sallows and poplars. A very distinctive species, with an exaggerated resemblance to a flake of rotten wood. Perhaps because of its camouflage, it is rarely seen except at light. The long feathery palps are found in both sexes, but their purpose is unclear. *Click on the image to enlarge it.*

	Fox Moth, Macrothylacia rubi Moorland, coasts, other open habitats. May and June. This is another species that is far more familiar as a big hairy caterpillar (see March) than as an adult. Very occasionally the female (illustrated) can be found resting on vegetation, while the smaller male flies rapidly in late afternoon sunshine, often fairly high. *Click on the image to enlarge it.*

	Drinker, Euthrix potatoria, caterpillar Fully grown in May or June. Tall grassland, damp moorland, marshes In western Scotland, this handsome caterpillar is a familar sight in late spring and early summer, though absent from the east. It rests openly by day, protected by its hairy coat from most birds - except Cuckoos. See July 2008 for the adult moth. Click on the image to enlarge it

	Pine-tree Lappet Dendrolimus pini Two-year life cycle, with adults flying in midsummer. Pinewoods and plantations. Whether a recent arrival or overlooked native, this fine large moth is a welcome addition to our fauna and most unlikely to become a pest. The caterpillars feed high in the treetops and are rarely seen. *Click on the image to enlarge it.*

	Small Dark Yellow Underwing Anarta cordigera late April through May. Caterpillars feed on Bearberry. This is one of the few Scottish specialities to be causing genuine concern, with few recent sightings. Moths fly rapidly in sunshine over Arctostaphylos heath, but are most easily found resting on rocks or fence posts in dull weather. All records will be welcomed. *Click on the image to enlarge it.*

	Red Twin-spot carpet Xanthorhoe spadicearia May and June. Heaths, moors, mosses and other open habitats. This carpet moth is at least partly diurnal and crepuscular, so does not often come to light. In our area it seems to be commoner in the east; further west the very similar Dark-barred Twin-spot Carpet replaces it. *Click on the image to enlarge it.*

	Lunar Thorn Selenia lunularia May into June. Woodland and scrub. Rarely numerous, Lunar Thorn is always a welcome find in the moth trap or at a lighted window. By day, its tattered dead-leaf camouflage helps to ensure it is rarely seen. The colouring of our Scottish examples is particularly deep and rich. *Click on the image to enlarge it.*

	Light Knot Grass Acronicta menyanthidis May and June. Upland heather moorland. Searching weathered fence posts in appropriate habitat is much the best way to find Light Knot Grass. Here a pair that mated the previous night is still present though now separated - a large, well-marked female of the scotica subspecies and a rather less impressive male. *Click on the image to enlarge it.*

	Nut-tree Tussock Colocasia coryli Deciduous woodland, parkland. Late April into June. This distinctive two-toned species has long vexed taxonomists. Now considered a noctuid rather than a tussock, its exact placing within that large and varied family is still uncertain. The adult does not feed and is rarely seen except when attracted to light. *Click on the image to enlarge it.*

	Large Red-belted Clearwing Synanthedon culiciformis Birch woodland, May into June. Much smaller than its English name suggests, this diurnal wasp mimic is rarely seen as an adult. Most records are of larval feeding signs or empty pupal cases, usually protruding from the stumps of recently felled birches along wayleaves and the edges of sunny rides. *Click on the image to enlarge it.*

	Barred Umber Plagodis pulveraria May into June. Deciduous woodland and scrub. In Scotland this is a local and mainly western species usually associated with hazel, a favourite larval foodplant. The adult's restricted palette and relatively simple pattern combined with freckling are characteristic of many moths in the subfamily Ennominae. *Click on the image to enlarge it.*

	Least Black Arches Nola confusalis May into June. Deciduous woodland. Formerly very local in Scotland, this species has greatly expanded its range in recent years. Its caterpillar feeds on the leaves of many deciduous trees such as rowan and birch (not on lichens, as was formerly thought). The adult rests head-downwards on trunks, often being mistaken for a micro-moth because of its small size. *Click on the image to enlarge it.*

	Small Chocolate-tip Clostera pigra May into June. Damp woodland and carr. This was always a local and infrequent species, but the recent NMRS atlas suggests an alarming decline in recent years. The only post-2000 dots in Scotland are from our Highland region, where the moth is associated with aspen rather than sallow. Though the adult is said to be partly diurnal it is rarely seen. Caterpillars are relatively easy to find in spun-together leaves at known sites. *Click on the image to enlarge it.*

	Flame Carpet Xanthorhoe designata May through to early September, often in two overlapping broods. Damp woodland, carr and scrub. Formerly this widespread moth produced a partial second brood in our area only during good summers, but in recent years it has become much more regularly bivoltine. Its caterpillar feeds on crucifers such as cresses, so it is commonest in damp open woodland. However, it is scarcer in urban or coastal areas, where the related species Garden Carpet (which also feeds on crucifers) replaces it. Click on the image to enlarge it.

	Clouded Silver Lomographa temerata May and June. Open woodland and scrub. Few moths are so pure a white as Clouded Silver. It may well be a recent arrival in our area, since older literature gives its northern limit as Argyll, and it is still quite local and infrequent here. Its caterpillar feeds mainly on rosaceous trees and shrubs such as hawthorn, blackthorn and wild cherry. The adult rests in the foliage and is easily disturbed by day. Click on the image to enlarge it.

	Iron Prominent Notodonta dromedarius May to August, probably in a mixture of one and two broods. Woodland and carr. The iron grey colour, complete with reddish streaks of rust, explains this moth's English name. Its scientific name, however, relates to its humped caterpillar (see Moths of the Month, August 2011). In drier areas birch is the foodplant, with alder used in wetter areas. Though widespread, this is a low-density species hardly ever found as an adult by day, and rarely numerous even in the moth trap. Click on the image to enlarge it.

	Scorched Wing Plagodis dolabraria May and June. Deciduous woodland, especially oak. This is also an aptly named species, looking as if it had only just escaped a fire with singed and buckled wings. It is yet another recent arrival in our area. Until a decade ago it was not known north of Perthshire. It is still local and far from numerous - species at the edge of their range need ideal habitat to compensate for barely suitable climate. As with most species in this subfamily, males come readily to light traps; the female (illustrated) is rarely found. Click on the image to enlarge it.

	Glaucous Shears Papestra biren May into June. Heathland and moorland. This is mainly an upland and inland species found on almost all our moors, where the caterpillar feeds on a wide variety of low plants and shrubs. Clearly it is habitat rather than foodplant that determines its distribution. The adult has a rather short flight period, peaking in the second half of May. At this time the adults can sometimes be found resting on fence posts, where their camouflage is slightly less effective than when they rest on rocks. Click on the image to enlarge it.

	May Highflyer Hydriomena impluviata May and June. Damp woodland and carr, riversides. Since alder is the only larval foodplant, May Highflyer is necessarily local, but it can be found almost everywhere that tree is present. Both parts of its scientific name reflect the habitat association with water. When freshly emerged the forewings are patterned in delicate shades of blue-green, but the colour is fugitive, bleaching within hours as in this wild example. By day the adults rest on alder trunks. Though almost impossible to spot, they take flight readily if the trunk is tapped with a stick. Click on the image to enlarge it.

	Knot Grass Acronicta rumicis May to July or later, perhaps with a partial second brood. Open habitats, including roadsides, gardens and coast. The English name associates this species with knotgrass Polygonum, while its scientific one specifies dock Rumex. In fact, its caterpillar feeds on almost any low-growing plant and many shrubs too, including those in gardens. The adult rests exposed by day on walls, fences, rocks or tree trunks. This dark example from Mull appears to be of the form lugubris Schultz, described by Kettlewell as an ancient west coast non-industrial melanic. Elsewhere the moths are a lighter grey. Click on the image to enlarge it.

	Green Silver-lines Pseudoips prasinana Mid May into early July. Good quality woodland. This lovely species can claim to be the most truly green of all our moths. Its scientific name and its placing in the systematic list have altered frequently over the years, but the latest molecular research suggests it is not a noctuid. In our area this is a local species found only in high quality woodland, especially oak. Even there the moth is never numerous. By day the adult rests openly on foliage, as its colour suggests. After dark, males are known to stridulate in flight, possibly in courtship, though very few observers have knowingly heard this. Click on the image to enlarge it.

	Brown Silver-line Petrophora chlorosata May and June. Almost anywhere with Bracken. Few species feed on Bracken, which contains unpleasant toxins. Brown Silver-line, whose caterpillars will eat nothing else, is therefore very unusual. Otherwise this is one of our plainest moths, with a simple disruptive crossline that hardly merits the term silver. Though mainly active at night, it is readily put up from the ground litter by day. Typically it flies a short distance before settlng again, a pale isosceles triangle amongst the dead fronds. Click on the image to enlarge it.

	Spectacle Abrostola tripartita May through to August, perhaps with partial second brood. Woodland and field edges, hedgerows, farmland, waste ground. Nettles are the foodplant of this ubiquitous species, so it is particularly numerous in lowland farmland with nitrogen-enriched soils. Because it overwinters as a pupa, Spectacle is the first of our plusias to appear in spring. The adult is hardly ever found by day, perhaps because its extravagant hair tufts disguise its shape so well. At dusk it is strongly attracted to campion flowers (which often grow alongside nettles) and also comes to light traps. Click on the image to enlarge it.

	Scalloped Hook-tip Falcaria lacertinaria May - July Birch woodland. This is a widespread but fairly local moth of good-quality birch woodland, and even there it is never very numerous. The long flight period in our area may include a partial second brood, since this species is bivoltine further south. The adult rests openly on foliage, often its host tree, relying for protection on its remarkable resemblance to a curled dead birch leaf. At night it is attracted to light, but not to nectar sources because it cannot feed. Click on the image to enlarge it.

	Lesser Swallow Prominent Pheosia gnoma May and June, then July and August. Woodland and heathland with birch. Although birch is the only foodplant, a few scattered trees are enough to support a population. In our area the flight period probably involves one extended main brood that merges with a partial second generation, particularly when a good summer follows an early spring. The adult's coloration mimics the bark of Silver Birch so well that even persons with no lepidopteral knowledge have correctly guessed the foodplant when shown the adult in a light trap. It is many years since I found my first, sitting with wings furled tightly round a birch twig, and can still remember my double-take on realising the slight bulge was a moth. In southern Britain the legs and thorax are light grey, but in the Scottish Highland a form where these are dark chocolate (as shown here) is equally common. Click on the image to enlarge it.

	Small Phoenix Ecliptopera silaceata May and June, then August and September. Road verges, woodland edge, farmland, gardens, waste land. This carpet moth feeds on willowherbs, whether belts of roadside rosebay or the smaller species that grow as garden weeds. Thus it can occupy a wide range of open and lightly wooded habitats, where it is often numerous. Though bivoltine further south, second brood examples were formerly unusual in our area, but have increased markedly in recent years. Several other carpets have a similar dark brown and cream colour pattern, but none in our area has the central band broken into islets, as shown here. Unfortunately some examples of Small Phoenix lack this feature, having the central band entire. The much less common Phoenix (see July 2010) is easily distinguished by its size alone, but the two can look very similar in voucher photos with no indication of scale. Click on the image to enlarge it.

	Currant Pug Eupithecia assimilata May into August, perhaps with partial second brood. Gardens, allotments, woodland edge. Because its larval foodplants are currants, gooseberry and hop, this pug is very much a suburban or rural garden species. Unsurprisingly, it is absent in more natural habitats where these plants are not present. Several other moths associated with currants have suffered major population declines in recent years, but Currant Pug seems as yet unaffected. Many of the small brown pugs look very similar, so the easiest way to record Currant Pug is by the feeding signs of its caterpillars. In late summer these make numerous small round holes in the lower leaves of currants, leaving them looking as if they had been hit by shotgun pellets. Turning such leaves over may reveal the long green caterpillar resting along a leaf vein. At dusk, the adults flit about the currant bushes and can be found by torchlight. They are sometimes attracted to lighted windows, and also feed on honeydew. Click on the image to enlarge it.

	Pale-shouldered Brocade Lacanobia thalassina May into July, in one extended brood. Woodland, scrub, hedgerows, rural gardens. Like many noctuids, Pale-shouldered Brocade can utilise a wide range of foodplants, from deciduous trees and shrubs to low-growing herbs. It is commonest in open woodland, but can also be found in many other habitats. The adult is all too similar to several other 'brocades'. Although the cream shoulder patch is a useful feature, this is more distinct in some individuals than in others. At night the moth seems more attracted to 'sugar' than to flowers or light, at least at my own site. Normally a moderately common species, it has occasional years of abundance before dropping back to its usual level. Click on the image to enlarge it.

	Birch Mocha Cyclophora albipunctata May into July. Birch woodland. Given the abundance of its favourite tree, Birch Mocha is surprisingly local in the Highlands. It appears to be choosy, requiring only the very best habitat as on Speyside or along the Great Glen. Even where present it is never numerous, with most records being of occasional singles. Scottish specimens are usually a silvery white, and the dark grey forms seen commonly further south are apparently absent here. The adults rest on the trunks and branches of their host tree, where they are well-concealed. Occasionally they can be found by day, or attracted sparingly to light after dark. Click on the image to enlarge it.

	Marbled Coronet Hadena confusa May & June. Coastal cliffs and shingle. In our area the chief foodplant of this moth is sea campion Silene uniflora, which is mainly found on coastal cliffs and shingle beaches. Inevitably, Marbled Coronet has a similar distribution, although like several other coastal moths it is also found inland on the Spey shingles. The caterpillar feeds entirely on the flowers and seeds of its host plant, living within the calyx while small but hiding in the debris beneath the plant by day once it grows too big to conceal itself within the pod. In some years every flower on a clump of sea campion shows feeding damage and every seedpod is eaten out, yet the following year the adult moth is not especially numerous. The adults can occasionally be found resting on rock faces, where their marbled pattern creates an effective disruptively cryptic camouflage, especially when the rock has lichens. At dusk they nectar avidly at the campion flowers, fertilising the seeds that in due course their caterpillars will consume. Click on the image to enlarge it.

	Ruddy Highflyer Hydriomena ruberata May & June. Moorland and carr with low sallow bushes. Ruddy Highflyer is more numerous in northwestern Scotland than anywhere else in Britain. In England and Wales this is a scarce and local moth, probably more so than the distributions maps suggest. Many of the older records for southern and eastern England are dubious, since the much commoner May Highflyer is easily mistaken for it. Whereas May Highflyer is found in alder woodland, Ruddy Highflyer is associated with low sallows, especially Eared Sallow Salix aurita, growing in damp montane moorland. The caterpillar lives between closely spun leaves, emerging from its habitation to feed at night elsewhere on the sprig, then returning home by dawn. Often the larval stage lasts well into September. The adult moth is out in spring, sometimes by late April. It rests on the sallow boles or nearby fenceposts. There is great variation in colour and pattern, with few as obviously ruddy as the Banffshire example illustrated here. Click on the image to enlarge it.

	White Ermine Spilosoma lubricipeda Late April well into July. Almost everywhere, including towns and gardens. This almost ubiquitous species has a single brood but a long flight period, from late April in early springs until mid July or even later, usually peaking in late May. Although numbers vary from year to year, it is rarely less than common and often abundant. Scottish examples tend to be cream or buff rather than white. The hairy caterpillar feeds on a wide range of low plants, including those in gardens, though never causing obvious damage. When fully grown in late summer it seeks a pupation site, crawling in broad daylight across roads and paths with great speed and urgency. This conspicuous habit explains Linnaeus's apt choice of specific name, which translates as swift-footed. Like most tiger moths, adults cannot feed, so are not attracted to nectar sources. They are sometimes found at rest low down in vegetation, occasionally as mated pairs. At night males especially are attracted to lighted windows and in much larger numbers to mercury vapour moth traps Click on the image to enlarge it.

	Purple Thorn Selenia tetralunaria May and June. Deciduous woodland. In Scotland, Purple Thorn is far more scarce and local than its relative, Lunar Thorn, the exact opposite of the situation further south. Its headquarters in our area are on Speyside and in the inner Moray Firth, but even there it is a notable find. Purple Thorn is single-brooded in the Highlands, flying between the two broods found in southern England. The moths are large and richly coloured, although maybe it is an exaggeration to describe them as purple. At rest they sit with partly opened wings, resembling a bunch of withered leaves. Because the undersides of the wings are exposed to view, these are as deeply coloured and as strongly marked as the uppersides, unlike in most other species. Inevitably, such a low-density moth is hardly ever seen except when attracted to a mercury vapour trap. Click on the image to enlarge it.

	Rivulet Perizoma affinitata May & June, sometimes later. Wherever red campion flourishes. Throughout most of Britain, Rivulet is a species of open woodland and waysides, where its grub-like caterpillar feeds within red campion seedpods and the adult flies at dusk. In our area, however, it is mainly coastal. It is abundant on the Banffshire coast where its foodplant thrives in the guano-rich grassland. There the males fly actively in the mid-morning sunshine, a dozen sometimes in view at once, while egg-laying females flutter gently amongst the campion in the late afternoon. In northern Scotland, many of our moths show slightly different habitat preferences and behaviour when compared further south, but Rivulet is an extreme example. Click on the image to enlarge it.

	Northern Eggar Lasiocampa quercus callunae Young larvae autumn to early spring. Heather moorland. Northern Eggar has a two-year life cycle, spending its first winter as a small caterpillar about an inch long. After hibernation these can be found in heather moorland basking in the spring sunshine, a habit shared with many hairy caterpillars. These early instars are more variable and more brightly coloured than the full-grown caterpillar, yet at the same time they are quite well-camouflaged amongst the old brown and bleached heather. Caterpillars and the resulting adults (see June 2015) are far more numerous in alternate years, odd or even depending on the region, probably due to an interaction with parasitoids. Click on the image to enlarge it.

	Beautiful Yellow Underwing Anarta myrtilli May into July. Heather moorland. This bright little arctic-alpine moth is probably present on every extensive heather moor, but recording it is not always easy. Because the adult is diurnal it never comes to light traps. Instead it is very active in bright sunshine, dashing about low over the heather, when the flash colouration of its black and yellow hindwings makes it hard for the eye to follow. In a brief glimpse it can be difficult to distinguish from some other insect such as a bee. Thus the high percentage of red pre-2000 dots on its distribution map should not necessarily be interpreted as a decline. Instead, there may well have been a significant range extension, since all records in the Outer Hebrides are post-2000. It might also be worth targeting old squares to re-find this species for the forthcoming distribution atlas. Click on the image to enlarge it.

	Lesser Yellow Underwing Noctua comes Caterpillar full-grown in May and June. Most habitats, including gardens. Lesser Yellow Underwing is among the most frequent caterpillars found by torchlight in spring, climbing plants and bushes to feed on the tender new growth. It is particularly conspicuous on broom, and on sallows when the buds are breaking. Yet this caterpillar is rarely seen by day. It descends before dawn to hide at ground level in the leaf litter, protected by its sombre colour scheme with disruptive markings. Many other noctuid caterpillars follow a similar strategy, which protects them from foraging birds but exposes them to predation from small mammals such as shrews and invertebrates including beetles. Presumably that risk is worthwhile, for the adult Lesser Yellow Underwing is generally common later in the year. Click on the image to enlarge it.

	Common Pug Eupithecia vulgata May & June. Most lowland habitats, especially gardens. As its name implies, Common Pug is the most ubiquitous of the numerous brown pugs that cause so many identification difficulties. It will be present in almost every garden. With practice, it can be recognised by its biscuit brown and grey colouration, numerous paler and darker crosslines, and inconspicuously small discal spot. Its build and wing shape are subtly distinctive too, for those with a good eye for jizz. On average, our Highland examples are more strongly marked than those from further south and have been given the subspecific name scotica, though whether they merit such status is questionable. Curiously, the guide books describe Common Pug as double-brooded, but I have never seen a second-brood example even during 25 years in Sussex, and certainly not in Scotland. Click on the image to enlarge it.

	Seraphim Lobophora halterata May into June. Aspen woodland. Since aspen is the only larval foodplant, this moth is inevitably a rather local if widespread species. The adult rarely strays far from its favourite tree. At known sites it can often be found resting on the trunks. On warm days it readily takes flight if disturbed, but then is often difficult to catch, quickly rising out of reach. Being so closely connected with one particular tree, Seraphim has adapted its camouflage to match. Though a variable species, many of its forms have a light yellow central band that ties in well with aspen bark, with a broad dark band towards the base of the forewing to disrupt the overall shape. As in several related species, the hindwings of Seraphim are disproportionately small compared with the forewings. This is a great help to identification when a captured moth is viewed from beneath in a clear container. Click on the image to enlarge it.

	Broad-bordered White Underwing Anarta melanopa May and June. Hills over 800m. This Scottish speciality is a high-altitude species, absent from lower ground even though its foodplant, Crowberry, occurs down to sea level. In our region it is mainly western, and should be sought wherever suitable habitat occurs. The adult is a stocky little moth. On sunny days it flies low and fast above the stunted montane vegetation, the flash colouration of its hindwings making it difficult for the eye to follow. Occasionally it pauses to feed at Trailing Azalea, one of the few nectar sources at such altitude in spring. However, when the weather is cloudy the chances of finding it are minimal even at well-known sites; at least, I have never yet succeeded. Its cryptic forewings would be effective camouflage either in low vegetation or on rocks. Click on the image to enlarge it.

	Garden Tiger Arctia caja Larva fully grown May-June. Most lowland habitats including gardens. Many caterpillars overwinter when small, then grow quickly on the lush spring foliage. Garden Tiger is one that sometimes takes advantage of the tender leaves of low sallow bushes, feeding openly by day. Its copious hairs protect it from most birds other than Cuckoo, but offer little protection against tachinid flies and other parasitoids. In parts of southern England this species has declined almost to rarity status, but still appears to be doing well in our area. Click on the image to enlarge it.

	Edinburgh Pug Eupithecia intricata May and June. Pinewood with a juniper understorey. Technically, Edinburgh Pug is the smaller and darker Scottish counterpart of Freyer’s Pug, a moth associated with garden cypresses in southern England. Formerly the two were separated by a gap in northern England, but recently Freyer’s Pug has advanced its range into Scotland. The races have now merged to create a hybrid population, intermediate in appearance, as far north as the Lothians. Pure populations of Edinburgh Pug still survive in our area, where the moth is often very numerous amongst native juniper. The distribution map picks out Deeside, Speyside and the inner Moray Firth as particularly favoured areas, but with surprisingly few records further west. Edinburgh Pug shares its foodplant with Juniper Pug, which is equally abundant. Competition is perhaps reduced by different life cycles and emergence periods: Edinburgh Pug overwinters as a pupa and emerges in spring, whereas Juniper Pug overwinters as an egg and flies much latter in the summer. Click on the image to enlarge it.

	Shears Hada plebeja May into July. Various open habitats. This compact little noctuid is almost ubiquitous, but perhaps most numerous on grassy moorland. Its caterpillar is presumed to feed nocturnally on a wide selection of low plants and weeds. At least it does so in captivity, but it is hardly ever found in the wild. The overwintering pupa has unusual lateral spine-like projections on four abdominal segments, perhaps enabling it to move around and escape unfavourable conditions such as waterlogging. The adult is sometimes discovered resting on rocks or fenceposts. Occasionally it flies in the sunshine, nectaring at flowers, but night is its usual time of activity. Click on the image to enlarge it.

	Dark Brocade Mniotype adusta Late May into July. Woodland and moorland. In Britain, Dark Brocade has increasingly become a species of the northern uplands, following a long slow retreat from southern England over the last century or more. Although it is still widespread in our region, there is some suggestion that numbers have gradually declined in recent years at more marginal sites. The moth itself is superficially similar to several other noctuids, but as the name suggests it is generally much darker, especially in Scotland. Even so, the flight histograms hint at a significant percentage of misidentifications, with records supposedly extending well into August and even later. At my own site the flight period is normally over by mid July. Though seldom found by day, the adult comes regularly to moth traps and also to sugar, but the caterpillar is rarely encountered – or at least, rarely identified. Click on the image to enlarge it.

	Netted Mountain Moth Macaria carbonaria Late April and May. Bearberry heath. As far as we know, Bearberry Arctostaphylos uva-ursi is the sole foodplant of Netted Mountain Moth in Britain, and even in Europe there are no records of it using Vaccinium species such as bilberry or cowberry. So the moth’s vernacular name is not particularly appropriate, as its habitat is undulating moorland rather than mountain peaks. Netted Mountain Moth is almost restricted to the central Highlands, with Speyside as its main area, but even here it is very local. Like its companion species Small Dark Yellow Underwing, there are worrying signs that it is decreasing, possibly due to climate change and also because of deteriorating habitat. At unmanaged sites Bearberry is eventually swamped by heather and bilberry, then by scrub. This moth has proved a difficult species to find in recent years. Both sexes fly actively in the sunshine. Netted Mountain Moth looks slightly bluish when in flight, helping to distinguish it from the similarly marked but slightly larger female Common Heath. It also flies more rapidly than the latter species and can prove quite difficult to net. Click on the image to enlarge it.

	Broad-bordered Yellow Underwing Noctua fimbriata Caterpillar full-grown in May or June. Woodland, scrub, hedgerows, sometimes gardens. The caterpillars of many noctuids overwinter when small, then feed up rapidly in spring. By day they hide in the leaf litter, then after dark they climb the stems to feed on the nutritious breaking buds of saplings and shrubs. Here they are easily spotted by torchlight before the leaves are fully developed. Although Broad-bordered Yellow Underwing is a rather low-density species, the large size and pale colouration of its caterpillar make it particularly conspicuous in the torch beam, while the row of six black spots beside the spiracles on the central sections are a sure means of identification. Curiously, the far more numerous final instar of Large Yellow Underwing seems never to climb shrubs to feed on buds in spring, but remains close to the ground at all times. Click on the image to enlarge it.

	Yellow-barred Brindle Acasis viretata Late April into June, with partial second brood. Open woodland, scrub, gardens. Although still a local species, Yellow-barred Brindle has increased considerably in our area in the past 20 years, though numbers remain relatively low. Further south this species has at least two broods, and even in the north occasional August examples are reported. When freshly emerged the moth is a deep mossy green as figured here, but this colour quickly fades or bleaches to a mustard or khaki yellow, especially during damp weather. As a result, nearly all wild-caught examples match their vernacular name. Such rapid fading is a feature of several green geometrids, so perhaps the green pigment is only needed to protect the moth when freshly emerged. The caterpillar lives mainly on the flowers and unripe berries of a wide variety of shrubs, including privet, ivy and holly, as well as more exotic species like viburnum and dogwood grown in gardens. Click on the image to enlarge it.

	Ochreous Pug Eupithecia indigata Late April and May. Pine forest. This is yet another of the confusingly similar little brown pugs, though it does have some distinguishing features. Its small size, coupled with long narrow forewings that are rather plain except for a large discal spot, help to rule out other species that fly at a similar time. While its colour is not strictly ochreous, there is often a faint sandy tint when slightly faded. The resting posture is also distinctive compared with other brown pugs, with the forewings sloping downwards to cover the hindwings, though this helpful clue is not mentioned in the guides. Ochreous Pug is a species of pine woodland, but despite what would seem a huge amount of habitat for such a small moth it is rarely recorded in numbers. Perhaps this is because the caterpillar feeds mainly on the male inflorescence, limiting its food supply and also restricting it to a single brood per year. And if the adult spends most of its time in the canopy, that might well reduce sightings. Click on the image to enlarge it.

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