Pearl-bordered Fritillary Clossiana euphrosyne, copulated pair, Hampshire – Adrian Hoskins

Introduction

The English name of this beautiful and increasingly rare species is derived from the row of silvery spots around the borders of the underside hindwings. The Latin name refers to Euphrosyne, the Greek goddess of Joy, and one of the three Graces.

The Pearl-bordered Fritillary is found across most of Europe but is absent from most of Ireland, and from Portugal and southern Spain. It is tolerant of cool climates, it’s range extending to northern Sweden, and across temperate Asia as far as the Tien Shan mountains.

It is often found at the same sites as the closely related Small Pearl-bordered Fritillary, but prefers drier conditions. The flight periods of the 2 species overlap, so worn specimens of euphrosyne can be seen in the company of fresh specimens of selene. The latter can easily distinguished by looking at the undersides, which have additional silver spots in the median area, and distinct black chevrons on the inner edge of the submarginal silver spots. The uppersides of selene have darker veins and more linear markings than euphrosyne.

Pearl-bordered Fritillary Clossiana euphrosyne, male, Hampshire – Adrian Hoskins

The flight period of the Pearl-bordered Fritillary is variable according to season, usually from early May until early June, but the butterflies can emerge in mid-late April in forward seasons, hence the old name “April Fritillary”. Click here to see the historic names of all British butterflies.

Habitats

The Pearl-bordered Fritillary was formerly widespread in Britain, and in the 1960’s was still regarded as fairly common in woods throughout England and Wales – in fact it was quite difficult then to find a wood where the butterfly did not occur. In the last 40 years however it has contracted it’s range dramatically – a result of the virtual cessation of coppice management in woodlands. Coppicing created a profusion of violets and nectar sources such as bugle, which are essential to the survival of the butterfly.

Neglect of historically coppiced woods and the coniferisation of almost all Forestry Commission land has eliminated most colonies in Britain. Populations continue to decline rapidly, and local extinctions are increasing. The butterfly now only occurs at about 70 sites in Britain, mainly in western counties of England, Wales and Scotland.

The butterflies breed in lightly wooded habitats where dog violets or marsh violets grow in profusion in small sheltered clearings, and where bracken is present but not dominant. Typical sites include hazel coppice, clearings and wide rides in coniferous or deciduous woodland, limestone pavements, and around the northern shores of Scottish lochs.

A typical colony in a small actively coppiced wood will contain less than 20 adults at peak season. In large Forestry Commission woodlands the butterfly is restricted to often very small areas where the foodplants and nectar sources thrive, e.g. where rides have been recently widened, or where new clearings have been created. These habitats are ephemeral by nature, and are only really suitable for the butterfly in the 2-4 years after felling and clearing takes place.

After that they quickly become overgrown, the foodplants and nectar sources get shaded out, and the butterflies disappear unless they can locate and colonise another suitable breeding area nearby. When the habitat is in perfect condition, and climatic conditions are ideal, huge populations of up to 1000 Pearl-bordered Fritillaries can build up in 2 or 3 years. Unfortunately they are short-lived, and numbers can drop to tens within 1 or 2 years, or disappear entirely, once the regrowth shades out the foodplants.

Pearl-bordered Fritillary Clossiana euphrosyne, male, Hampshire – Adrian Hoskins

Lifecycle

The butterflies lay their eggs singly or in pairs on dry bracken or dead grasses, choosing sheltered and semi-shaded situations where violets grow in profusion.

The larvae hatch after about 2 weeks, feeding diurnally on the leaves of dog violet Viola riviniana. In northern Britain V. palustris is more commonly used, and in Europe V. odorata and V. hirta are also commonly used.

In September when in the 4th instar they enter hibernation amongst leaf litter. The following spring, usually in late March, they awaken. On sunny days they can sometimes be seen basking on dead bracken and oak leaves on the forest floor. They continue feeding on violet leaves, becoming fully grown in April. The mature larvae are black, adorned with bright yellow-orange spikes along the back. In mid April they wander in search of a pupation site. The greyish brown pupa hangs by the cremaster from a dry stem, close to the ground.

Occasionally a partial 2nd brood emerges in August but this is extremely unusual in Britain even in very warm summers.

Adult behaviour

On sunny mornings male Pearl-bordered Fritillaries fly rapidly and in broad circles, with a flit-and-glide motion, just above the herb layer. They periodically dip down to gorge themselves on the nectar of their favourite flowers – bugle. When feeding they adopt a head-downwards posture, as they have a short proboscis and cannot easily reach into the flowers when in an upright position. They occasionally visit other flowers including ground ivy, wood anemone and dandelion; and in the New Forest I once saw one nectaring at hawthorn blossom.

Male-male encounters result in a brief dog-fight lasting only a few seconds, after which each goes their separate way.

The females are probably mated very soon after emergence, and in many cases before their maiden flight. Copulation takes place in late morning or early afternoon, and lasts about an hour. Afterwards the females spend most of their time delicately fluttering in and out amongst areas of dry grass and dead bracken, searching for egg-laying sites. They are capable of a fair turn of speed if disturbed however.

In cloudy but bright weather, both sexes spend short periods basking, sometimes on logs or bare earth, but more commonly on dead bracken. Overnight, or in heavily overcast weather, they roost in sheltered situations, typically on bracken fronds, on the dead flower-heads of St Johns wort, or on the leaf buds of pine saplings. In wet weather they roost tucked under dead bracken and leaf litter.

Pearl-bordered Fritillary Clossiana euphrosyne, male at roost, Hampshire – Adrian Hoskins

Pearl-bordered Fritillary Clossiana euphrosyne, male at roost, Hampshire – Adrian Hoskins

Queen of Spain Fritillary, female nectaring at thistle – Adrian Hoskins

Queen of Spain Fritillary, female – Adrian Hoskins

Introduction

The Queen of Spain Fritillary is a fairly common butterfly in Europe and temperate Asia, but it only occurs in Britain as an extremely rare migrant, in fact there have been less than 400 records of this species since it was first recorded 300 years ago by William Vernon at Gamlingay, Cambridgeshire. The biggest migration was in 1872 when 50 were recorded in Britain, and in 1945, no less than 25 adults were recorded from Portreath in Cornwall, indicating that the butterfly had successfully bred there.

However there have been many years when not even a single specimen has been recorded anywhere in Britain, although there are possible indications that migrations may be increasing, most likely as a result of climate changes increasing the butterfly’s abundance in northern France.

An unusually high number of adults were recorded in 2007, when 6 were reported from various parts of Hampshire and Sussex. These migrations seem to originate from Normandy, and funnel into the UK via river valleys. Small migrations also took place in 2008 & 2009. In the latter case a single female arriving in West Sussex in July produced offspring which emerged in September and October – at least 7 different adults were recorded, including a mating pair on October 13th.

The very distinctive large silver spots on the underside hindwings mean that this butterfly is unlikely to be confused with any other species, although early summer specimens could possibly be mistaken in flight for a Pearl-bordered or Small Pearl-bordered Fritillary. In late summer or early autumn they could be confused in flight with a Wall Brown but the differences are obvious as soon as the butterfly settles.

Both sexes are very similar in appearance, although the female is slightly larger, with a shorter abdomen and a more greenish hue around the base of the upperside wings. The sexes can more easily be distinguished by their behaviour – females are sedentary, while males actively pursue all passing butterflies.

Queen of Spain Fritillary, female basking on maize – Adrian Hoskins

Habitats

This species breeds in a diverse range of habitats in Europe, ranging from hay meadows to heaths and woodlands. It tends to breed mainly in lowland areas but tends to migrate to higher altitudes particularly if the summer has been warm and dry, when it can be found up to an altitude of at least 2000m in the Alps and Pyrenees.

In Britain it requires warm dry habitats to breed successfully, but such events are extremely rare. In 2009 a female recorded on 14th July laid eggs at a farmland site in Sussex where the larval foodplant field pansy Viola arvensis grew around the margins of a maize crop. The progeny began to emerge in mid September and remained on the wing until mid October, with a maximum of 6 adults at the peak of the flight.

Queen of Spain Fritillary, basking on bramble – Adrian Hoskins

Queen of Spain Fritillary, basking on bramble – Adrian Hoskins

Lifecycle

In Europe there are 3 generations of this species, emerging in March/April, July, and September in lowland areas. In montane areas there is usually only a single brood which emerges in late June and remains on the wing until the end of August. Hibernation can occur in any stage of the lifecycle depending on location and climate, but most commonly occurs in the egg stage or as young larvae.

In Britain migrants usually arrive either in May or July, and if they breed here the progeny normally emerge in mid-late September. Eggs from the UK bred generation hatch after about a week.

The pale straw coloured eggs are conical in shape, with about 40 longitudinal keels. They are laid singly on the stems and leaves of the foodplants, and probably also on surrounding stems and leaf litter. Oviposition sites are invariably in dry sheltered situations where vegetation is sparse. Reportedly as many as 100 eggs can be laid by a single female per day in captivity.

The caterpillars are velvety black, heavily sprinkled with tiny white dots, and adorned with rows of dull orange spikes along the back and sides. They feed on field pansy Viola arvensis, wild pansy V. tricolor, and sweet violet V. odorata, but do not normally feed on other Viola species.

Prior to pupation the larvae wander aimlessly for 2 or 3 days without feeding, and eventually attach themselves by the tail to a button of silk spun on the underside of a leaf, or a low stem. The pupa, which wriggles frantically if disturbed, is blackish-olive colour, marked with small white patches on the abdomen, which is adorned with a series of stubby white spikes. It bears a strong resemblance to a bird dropping. The adult butterflies emerge in the morning, about 10-12 days after pupation.

Queen of Spain Fritillary, male nectaring at yarrow – Adrian Hoskins

Queen of Spain Fritillary, female – Adrian Hoskins

Adult behaviour

Males tend to bask on flat dry paths, where they regulate their body temperature either by holding their wings in a “V”, or spread flat on the ground, depending on ambient conditions. They dart up to investigate passing butterflies, even those that could not possibly be mistaken for their own kind. In October 2009 for instance, at Chichester in Sussex, I witnessed a 3-way territorial “dog-fight” when a male dashed up from his perching place to intercept a pair of sparring male Clouded Yellows.

Both sexes visit a wide variety of flowers for nectar, including thistles, hawkbit, cow parsley, thyme, dandelion, hemp agrimony, marjoram, yarrow and bramble blossom. When nectaring the wings are normally held almost fully outspread. In the Alps and Pyrenees I have often seen males imbibing at the edge of puddles, and at these times the wings are normally held erect.

The adults are not particularly wary of humans, and tend to fly a short distance and resettle on the ground a few metres away if disturbed. They have a zigzag fluttery flight low over the ground, but males often fly over bushes, or soar up a slope, or over the edges of tall crops for a few moments before circling around and returning to a favoured warm sheltered spot.

Roosting probably takes place mainly in the tree tops – in Sussex e.g. where the species bred at the edge of a maize field in 2009, both sexes regularly roosted at the top of oaks and sweet chestnuts in late afternoon. At the same site however they were also found roosting among herbage and on thistles and knapweed flowerheads. I also watched 2 males go to roost on maize plants, where they settled hanging beneath broad dry leaves high up on the plant.

Queen of Spain Fritillary, female – Adrian Hoskins

Introduction

The genus Argynnis comprises of about 25 species, found variously in Europe, temperate Asia and North America. Certain workers include an additional 18 Speyeria species within Argynnis.

The Dark Green Fritillary, formerly known as the Queen of England Fritillary is widely distributed across Europe but absent from most Mediterranean islands. It is also found throughout temperate Asia as far east as Japan, and occurs in the Atlas mountains of Morocco.

The common name refers to the bronzy-green underside wings, which are spangled with large silver spots.

Dark Green Fritillary Argynnis aglaia male, Arnside Knott, Cumbria – Adrian Hoskins

The upperside wings of males are bright unicolorous orange, with black spots. Females are variable in ground colour, some being a dull reddish brown ground colour while others have a distinct bronzy sheen. In females the colour is often paler near the apex and wing margins, while the basal area of the forewings is noticeably dark. In Scotland both sexes tend to be larger and more heavily marked than elsewhere in the butterfly’s range.

The butterfly can easily be confused with the High Brown Fritillary Argynnis adippe, but the male of that species has short wide sex brands on veins 2 and 3 ( as opposed to the long narrow brands on veins 1, 2 and 3 in aglaia ). The High Brown Fritillary also has slightly concave outer margins to the forewings. On the underside adippe has a more yellowish ground colour, and an additional band of small silver sub-marginal spots that are ringed with dark red.

On Corsica the Dark Green Fritillary is absent, being replaced by the endemic Argynnis elisa, which is very similar to aglaia but is smaller and has greatly reduced black markings on the upperside.

Dark Green Fritillary Argynnis aglaia male, Arnside Knott, Cumbria – Adrian Hoskins

Habitats

This is the most widespread and least threatened of Fritillaries in Britain. In southern England it is a butterfly of wild, windswept open grasslands and cliff-tops, but also occurs on heathlands, dunes and in forest clearings. In northern counties it is found on moors and mountain valleys and can also be found in the company of the High Brown Fritillary in grassland / woodland mosaics on limestone.

In Scotland the butterfly is found on moors and mountainsides, in woodlands, and on open grassy habitats. It is the only Fritillary which occurs on the windswept islands of the Orkneys and Outer Hebrides.

Although it is very widespread and utilises a very broad range of habitats, populations are localised with very little movement between sites. They also tend to be confined to particular areas of each site, often restricted to sheltered pockets where the soil is deep, and violets grow in large clumps.

European populations are far less restricted by habitat, being found in lowland meadows, limestone gorges, sub-alpine hay meadows and many other habitats.

Dark Green Fritillary Argynnis aglaia, female ab. obsoleta, Pitt Down, Hampshire – Adrian Hoskins

Lifecycle

The eggs are straw coloured with purplish bands. They are laid in July or early August on leaves or stems in the vicinity of the larval foodplants, but not usually on the foodplant itself. At Dean Hill in July 2007 for example I observed a female enter a clump of dead grasses and twigs, upon which she laid 6 eggs dotted about on different stems over a period of 2 or 3 minutes. Violet plants Viola hirta were profuse in the area, the nearest plant being about a metre from the oviposition site.

At chalk and limestone grassland sites the usual foodplant is hairy violet Viola hirta, but in southern woodlands common dog violet V. riviniana is normally used. On heaths in the New Forest, and on moors in Cumbria and Scotland, V. palustris is favoured.

The larvae hatch in August, about 16 days after the eggs are laid. After eating the empty egg-shells they immediately enter hibernation. They over-winter in curled up dead leaves, or in chinks on the bark of bushes. The following March they awaken to feed on violet leaves, nibbling large chunks out of the lobes. In southern England they become fully grown in early May. In Scotland I’ve often found fully grown larvae wandering across country roads as late as the first week of June.

When fully grown they are mottled in black and grey, adorned along the back and sides with rows of branched black spikes, and have a yellow stripe along the back. There is a row of dark reddish spots low down on the sides, and the head is black and glossy.

The chrysalis is shiny, with black wing-cases and a dark brown abdomen. I have found it in the wild in Scotland formed amongst bracken and leaf litter, suspended by the tail from a dry stem, and protected amongst a cluster of dead leaves spun together with silk.

Dark Green Fritillary Argynnis aglaia female, Farley Mount, Hampshire – Adrian Hoskins

Adult behaviour

At grassland sites in southern England the butterflies nectar on knapweeds, almost to the exclusion of other flowers, but in woodland they will feed at bramble, spear thistles, bird’s foot trefoil, clovers, buddleia and hawkbit. They usually spend several seconds nectaring at each flower before flying rapidly to another plant perhaps 100 metres distant, even if other flowers are situated nearby.

Dark Green Fritillaries are extremely alert, agile and powerful on the wing, and seem to relish flying in the face of the strong breezes which prevail at their open windswept habitats. In rainy weather they crawl deep into grass tussocks but they still remain very alert – the tiniest disturbance causes them to fly up instantly, dashing off in search of a new resting place.

Throughout the day males patrol relentlessly back and forth across their habitat, soaring effortlessly in the face of the strongest winds. They dip down periodically, searching for females, which sit deep in grass tussocks prior to mating. Once a female is located, copulation takes place immediately with no apparent courtship ritual. Mated pairs occasionally fly in tandem to nectar at flowers, but spend most of the time sitting hidden among the grasses, with the wings held erect or half open.

In overcast or cool conditions the butterflies often remain fairly active, but spend long periods basking in rabbit scrapes, patches of bare earth, or amongst grasses. At Martin Down in Hampshire I once discovered a male Dark Green Fritillary which had settled to bask on a coiled grass snake !

Shortly before dusk on sunny days, the butterflies migrate across their habitat to bask in the last remaining sunlit areas, and can often be seen in the company of Marbled Whites, soaking up the last rays of the sun. As the sun dips below the horizon, they undertake a final flight to locate a roosting site – often this can be high in a tree, but more frequently they roost hanging from grass heads in areas where the grasses grow tall, or on low bushes of dogwood or buckthorn.

Dark Green Fritillary Argynnis aglaia male, Arnside Knott, Cumbria – Adrian Hoskins

Silver-washed Fritillary Argynnis paphia male, Wiltshire, England – Adrian Hoskins

Introduction

The genus Argynnis comprises of about 25 species, found variously in Europe, temperate Asia and North America. Certain workers include an additional 18 Speyeria species within Argynnis.

The Silver-washed Fritillary is one of Europe’s largest and most magnificent butterflies. The common name refers to the suffused silvery markings on the underside hindwings. The male, shown above, is easily distinguished from the female by the 4 prominent horizontal dark streaks on its forewings. These contain androconial scales, from which pheromones are released during the courtship flight.

Silver-washed Fritillary Argynnis paphia female, Wiltshire, England – Adrian Hoskins

Females have a similar pattern of black spots, but lack the horizontal streaks. They are normally a dull golden colour, often with a slight bronzy tinge. The greyish female depicted below is the scarcer and very beautiful form valesina. It only occurs at a few sites, usually in long established colonies in oak forests. Captive breeding experiments have proven that about 10% of females in Hampshire, Wiltshire and Dorset are of the valesina variety. The numbers actually observed in the wild however are much lower as they are more secretive in behaviour than normal females. The common name refers to the suffused silvery markings on the greenish underside hindwings.

Silver-washed Fritillary Argynnis paphia female form valesina – Adrian Hoskins

The butterfly is common and widely distributed across much of Europe, but absent from northern Scandinavia, northern Britain, and the southern parts of the Iberian peninsula. Beyond Europe it occurs in northern Algeria, and is widespread across temperate Asia to China, Korea and Japan.

Argynnis paphia males basking on bracken in early morning – Adrian Hoskins

Habitats

The Silver-washed Fritillary prefers slightly shadier conditions than most other woodland Fritillaries and is better able to survive in high canopy forests and woods that have become neglected and overgrown. The highest populations occur in mature oak and beech plantations where a program of regular thinning encourages a profusion of dog violets to germinate beneath the trees. The best sites are also typified by having glades and grassy tracks where thistles, brambles and other nectar sources are abundant.

The butterfly is a powerful flyer and quite mobile, being often found on scrubby downland or along hedgerows or railway cuttings where these habitats are close to its woodland homelands. Thus it is able to recolonise neglected woods which have been thinned or returned to coppice management and once again become suitable as breeding sites.

In the early 19th century this species was found as far north as Dumfries, but has always been very scarce in northern Britain, and has been extinct in Scotland for about 150 years. There was however a freak migration in 1910, when the species found its way as north as Aberdeen. The butterfly is still very rare north of a line running from Liverpool to Peterborough, but has recently shown signs of expansion, probably as a result of climate change. In 2009 for example I found a fresh male Silver-washed Fritillary visiting bramble blossom in a wood near Witherslack in Cumbria.

Silver-washed Fritillary Argynnis paphia males at bramble, Hampshire – Adrian Hoskins

Lifecycle

The butterflies emerge in June and July and have a life expectancy of about 3-4 weeks, although many are killed by birds before fulfilling their potential life spans.

The greenish-white eggs are laid singly in crevices in the bark of oaks, and more rarely on other trees including beech, ash and larch; normally at a height of about 2 metres, on the moss-covered east or north-facing side of the trees. The trees chosen tend to be about 50-100 year old specimens growing along the edges of rides, and illuminated by dappled sunlight. Often a female will revisit the same favoured tree trunk, laying a dozen or more eggs in the space of an afternoon.

Immediately after hatching in August, the tiny caterpillars eat their egg-shells, which contain vital nutrients. They then attach themselves to a little pad of silk which they spin on the tree trunk, and enter a state of diapause, remaining hidden in a chink in the bark until the arrival of sunny weather in March of the following year. They then descend the trees and wander in search of dog violets Viola riviniana. They feed diurnally, eating only the lobes of the violet leaves, and then move on to another plant. The fully grown larvae can sometimes be found basking on dead oak leaves in May or early June. They are black, marked with a double yellow line along the back, and have a series of dull orange branched spikes on the back and sides. The 2 spikes on the first segment are black, and inclined forward over the head.

The slightly spiky pupa is mottled in shades of brown, and decorated with golden spots. It is almost impossible to find in the wild, but is reportedly suspended by the cremaster from the woody stems of bushes, or from twigs on oak trees. The pupal stage lasts for about 3 weeks.

Silver-washed Fritillary Argynnis paphia, Hampshire – Colin Baker

Adult behaviour

The first males emerge in late June, appearing about a week before the first females. Individuals can live for up to a month, with worn specimens seen as late as early September.

Overnight, and during dull weather, the butterflies roost amongst oak leaves high in the tree tops. In the early morning they bask high up until the rays of the sun reach the forest floor, and then drift down to continue basking on bracken, hazel leaves, and other low vegetation.As the day warms up they become more active, nectaring avidly at thistles, bramble blossom, hemp agrimony, hogweed and ragwort. Both sexes also imbibe honey-dew from the surface of leaves, and males often settle on stony tracks to imbibe mineral-rich moisture.

Silver-washed Fritillary Argynnis paphia males, Wiltshire ï¿½ Adrian Hoskins

The courtship ritual of the Silver-washed Fritillary is one of the most endearing and familiar sights of the English summer. The female flies in a straight line along woodland tracks at a height of about 2 metres, and as she does so she emits an aphrodisiac scent from the tip of her abdomen. The male responds by following her closely, repeatedly looping under and over her, and showering her with pheromones released from the 4 black bars of androconial scales which run along the veins of his forewings. In many cases this tantalising display fails to entice the female into mating, but if she is receptive she leads the male to a clump of leaves high in an oak tree where copulation takes place. Periodically the pair fly down to settle on bracken or hazel, or to nectar at bramble, but return to the tree tops if disturbed. Copulation lasts about 2 hours and usually takes place in late morning.

Silver-washed Fritillary Argynnis paphia female, Straits Inclosure, Hampshire – Adrian Hoskins

Silver-washed Fritillary Argynnis paphia male, Bentley Wood, Wiltshire – Adrian Hoskins

Introduction

The Comma was regarded as a common species in the 18th century but declined to became a great rarity between about 1850 and 1910. By 1930 it was on the verge of extinction but then it’s fortunes began to reverse. By the 1980’s its numbers had completely recovered and it is now once again a common species in southern Britain.

The butterfly gets its common name from the C or comma-shaped silver mark on the underside of the hindwings. The genus name Polygonia is a reference to the beautiful ragged wing shape. This is unique among British butterflies but there are other similarly shaped species found elsewhere in the Holarctic region, including the Southern Comma P. egea which inhabits the Mediterranean area, and the Question Mark and Angle-wing butterflies of North America.

Polygonia c-album, male at roost on birch sapling, Stansted Forest, West Sussex – Adrian Hoskins

The Comma is distributed across most of Europe, but absent from Scotland and sub-arctic regions. Beyond Europe it occurs across temperate Asia to northern China, Korea and Japan. It also occurs in Morocco, Algeria and Tunisia.

Comma Polygonia c-album, male, March, Stansted Forest, West Sussex – Adrian Hoskins

Comma Polygonia c-album, f. hutchinsoni, June, Stansted Forest, West Sussex – Adrian Hoskins

Habitats

In spring Commas breed primarily in woodland edge habitats where stinging nettles grow in damp but sunny situations, typically in glades or at the side of grassy tracks. The summer adults are more mobile however, and can breed in gardens, old quarries, along country lanes and railway cuttings, on sheltered areas of scrubby grassland, and at coastal habitats. They freely roam the countryside and can be found anywhere where stinging nettles or elms grow but favour sunny sheltered sites with bramble bushes nearby, and a profusion of wild flowers.

Polygonia c-album, f. hutchinsoni, July, Titchmarsh Wood, Northamptonshire – Adrian Hoskins

Lifecycle

There are 2 generations each year. Larvae hatching from eggs laid in early March by overwintered females develop slowly, pupating in mid-June to produce adults of the brightly marked hutchinsoni form. These emerge in early July and remain on the wing until mid-August. The overwintered adults however remain alive until late spring and continue laying eggs until mid-May. Larvae hatching from these later eggs develop more slowly to produce normal adults which emerge in August.

Meanwhile the offspring of the hutchinsoni brood produce another generation of normal adults which emerge in September. In late summer it is possible to see both forms flying together. The hutchinsoni adults die by early September. The normal form adults enter hibernation and awaken the following spring.The green, ribbed eggs are laid singly, close to the edge on the upperside of stinging nettle leaves. Commas normally oviposit on nettles growing in sheltered situations along hedgerows or in sunny woodland glades, close to nectar sources such as blackthorn ( spring ) or bramble (  summer ).

Two hundred or so years ago the primary foodplant used in Britain by Commas was hop Humulus lupulus, which was grown all over southern England as an ingredient for ale. The dramatic decline of the butterfly in the late 19th and early 20th centuries is probably linked to changes of practice which greatly reduced this formerly widespread and abundant plant.

Fortunately the Comma was able to adapt to making widespread use of another foodplant, stinging nettle Urtica dioica and this has now  undoubtedly become the primary foodplant in Britain. Larvae are also found occasionally on sucker growth of English elm Ulmus procera, and more rarely on wych elm U. glabra, sallow Salix caprea, hazel Corylus avellana, or cultivated blackcurrant Ribes nigrum.

The fully grown caterpillar is unmistakable, being brownish black, with orange spikes on the front segments, and a long splash of white along the back. It often rests on the upper surface of a leaf, adopting a semi-curled posture, and at a glance can be mistaken for a bird dropping. The chrysalis is marbled in shades of brown, and decorated with spangles of silver and gold. I have occasionally found pupae attached to fence posts, but they are more often found suspended from woody stems or shaded tree trunks.

Comma Polygonia c-album, Steyning, West Sussex – Adrian Hoskins

Adult behaviour

In spring Commas occupy ride intersections and glades, where they nectar at blackthorn blossom, sallow catkins and dandelions. They spend long periods basking on leaf litter, bare ground, on logs, or on bramble leaves or dead bracken. It is also common to see them basking head-downward on fence posts, or on the trunks of birch and ash trees.

In the spring males establish territorial perches on twigs, logs or favoured leaves which they use as bases from which to launch flights to ambush other passing butterflies. Intruding male Commas and butterflies of other species including Peacocks and Orange tips are always ousted by the ‘owner’ of the territory. Summer brood Commas often perch on hazel bushes and intercept Gatekeepers and Speckled Woods. Passing female Commas are intercepted, but I have never witnessed a courtship ritual, or found any mated pairs. Copulation reportedly takes place high in the tree tops.

Comma Polygonia c-album, Stansted Forest, West Sussex – Adrian Hoskins

On warm sunny days in spring, butterflies of both sexes frequently settle on paths, tree stumps or wood shavings to imbibe moisture. Summer nectar sources include bramble, hemp agrimony, wild carrot, marjoram, thistles and traveller’s joy.

In cool cloudy weather, Commas roost openly on foliage, and if disturbed will feign death, falling to the ground, with their wings closed and their white legs tucked tightly against their bodies. Towards dusk they seek overnight roosting sites. One evening in early July 2009, I watched a female settling down to roost – she spent a couple of minutes fluttering around on the shady side of an ivy covered fence, and eventually settled for the night under an ivy leaf, resting on the mid-vein, with her head pointing towards the stem.

On various occasions I have also found Commas roosting at ground level among grasses – in these cases the butterflies always roost head-downward. Their disguise is quite remarkable, giving the impression of a dead oak leaf that has fallen onto the grass.

Comma Polygonia c-album, July, Alice Holt forest, Hampshire – Adrian Hoskins

In early autumn the butterflies nectar avidly at devilsbit scabious, buddleia, ragwort and fleabane in preparation for hibernation. The feeding frenzy continues into September and October when they nectar at ivy, and gorge themselves on sugary juices exuding from fermenting blackberries.

In late October they seek out hibernation sites, usually choosing to spend the winter months hiding in wood stacks, hollow tree trunks, or sometimes out in the open, hanging beneath branches. The butterfly depicted below was found hibernating under a branch of young coppiced sweet chestnut, about 0.5m above ground level in Stansted Forest.

I found it on 26th January 2008 but suspect that it had been hibernating there since the previous October. It was still there in the same position on 9th February, but by 24th February had disappeared, presumably having awoken from it’s diapause with the arrival of sunny and slightly warmer weather.

Comma Polygonia c-album, hibernating openly under a low branch – Adrian Hoskins