This butterfly, the largest of our 'browns', is a master of disguise - although fairly conspicuous when in flight, it can mysteriously disappear as soon as it lands, perfectly camouflaged against a background of bare earth and stones, always resting with its wings closed. When it first lands, and when disturbed, the butterfly will raise its forewings for a second or so, revealing dark eye spots that stand out against a beautiful spectrum of browns. This butterfly also has a curious technique for regulating body temperature by leaning its wings at different angles to the sun.
This butterfly is known for the variation between geographically-isolated populations, with 6 named subspecies occurring within the British Isles. This butterfly forms discrete colonies and, while some colonies are inland, the overall distribution of this butterfly would suggest that this is primarily a coastal species, at least in the British Isles. This butterfly is found on the Isle of Man and in the Channel Islands, but is absent from Orkney and Shetland. Colonies vary considerably in size, the smallest containing a couple of dozen and the largest several thousand - especially those found on large expanses of land, such as the heathlands of the New Forest.
This subspecies was first defined in Thompson (1944) as shown here (type locality: Creuddyn Peninsula, Caernarvonshire, North Wales). This subspecies is confined to the western side of the Great Ormes Head near Llandudno in Denbighshire, North Wales. It differs from the subspecies semele as follows:
1. Considerably smaller in size, a characteristic that was analysed in some detail by Dennis (1972).
2. The underside has less contrast, with pale areas tinged with ochreous.
3. The forewing spots are smaller, with the lower spot occasionally absent.
4. It flies several weeks earlier.
Hipparchia semele ssp. thyone (Thompson, 1944)
Male. Strikingly smaller than any other British race of semele, those in my series of over 100 specimens, collected at random, averaging only 47.7 mm.
The coloration is more uniform than in typical semele, with the pale areas more ochreous. The forewing spots are smaller than in other races, with the lower of the two frequently absent, and totally obsolete specimens are not very rare. The underside has the coloration duller and less contrasting than in the type, with the white portions of the hindwings tinged with ochreous. The tendency to obsolescence is even more striking on the under surface than on the upperside.Female. Similarly smaller than other races, those in my series averaging 51.1 mm. The comparatively unicolorous tendency is the same as in the male; but obsolescence is less marked, although the spots are smaller than in normal specimens. The underside presents peculiarities similar to males of this race.Habitat: Creuddyn Peninsula, Carnarvonshire. Types: Male, female, 2nd July 1941, in my collection.E. semele ssp. thyone flies earlier than is usual with other races, being on the wing towards the third week in June, and disappearing by the end of July.
This subspecies was first defined in Verity (1911) as shown here and as shown in this plate (type locality: Northern Scotland). This subspecies is generally distributed around the coast of Scotland, with the exception of the western Isles which is populated by the subspecies atlantica. It differs from the subspecies semele as follows:
1. Slightly smaller size.
2. Upperside fulvous markings extensive but very pale, almost yellow.
3. Underside of the hindwings with extensive and very dark marbling. Dennis (1977) states that the white transverse band on the hindwing is not lacking, as its formal definition suggests, but is "variably expressed".
Hipparchia semele ssp. scota (Verity, 1911)
Taille très réduite (envergure : 45-50 mill., au lieu de 48-60 mill.; dessins fauves plutôt étendus, mais très pâles, presque jaunes; revers des postérieures extrèmement obscurs et sans bande blanche transversale; la marbrure est d'un noir profond et extrêmement abondante, ce qui donne à l'aile un aspect complètement différent de celui du type.Habitat. — Ecosse septentrionale. Types : coll. Vérity.TranslationSize much reduced (wingspan: 45–50 mm, instead of 48-60 mm); fulvous markings rather extensive but very pale, almost yellow; underside of the hindwings extremely dark and lacking a white transverse band; the marbling is deep black and very copious, giving the wings a completely different look from that of the type.Habitat – Northern Scotland. Types: Vérity collection.
1. In general it has a brighter appearance with more contrasting colours.
2. The underside is blacker and the yellow portions more orange.
Hipparchia semele ssp. atlantica (Harrison, 1946)
Well distributed on the sand dunes on Coll and Gunna. The form, which agrees racially with examples collected on Sandray, Pabbay, and Vatersay in the Outer Island and in Rhum and elsewhere in the Inner Hebrides, is separable from mainland examples by its brighter and more contrasty colouration. In particular, the under surface of the wings is blacker and the yellow portions more orange. This insect may be known as subsp. atlantica, the type, in my possession, originating in Vatersay.
This subspecies was first defined in Howarth (1971-1) (type locality: Killarney, County Kerry, Ireland). This subspecies is found throughout Ireland, primarily in coastal areas, with the exception of the Burren in Clare and South-east Galway, where the subspecies clarensis is found. Dennis (1977) says "This subspecies is clearly similar to the Scottish race [ssp. scota], and only differs in its warmer brown tone and the unicoloured rather than variegated brown of the hindwing margins". Subspecies hibernica differs from the subspecies semele as follows:
1. The upperside is a warmer brown, with pale markings that are reddish brown in tint.
2. The upperside of the female often has some reddish suffusion.
3. The underside has dark markings that are more chocolate-brown, with a darker basal area.
4. The underside of the hindwings has deep uniform brown margins.
Hipparchia semele ssp. hibernica (Howarth, 1971)
The males have the upperside ground colour a warm brown with the paler markings more rufous in tint compared with English examples (ssp. anglorum Verity [Verity (1924)]). On the underside the dark markings are more chocolate-brown and the bases of the hindwings are darker.
The females differ in the same manner as the males and on the upperside of the forewing often possess the reddish suffusion in spaces 2 and 3 which sometimes extends into the discoidal cell.In several respects this newly described subspecies is rather similar to ssp. scota Verity, as one would expect, but it is generally a warmer brown and has the margins of the hindwings a deep unicolorous brown compared with the more variegated margins of scota, which have a sharply defined black inner edge.Holotype male: Kerry, Killarney, P. Bouchard 64.69 (pl. 1 fig. 5).Allotype female: Same data as holotype (pl. 1 fig. 6).[Paratypes listed].
This subspecies was first defined in de Lattin (1952) as shown here (type locality: County Clare, Ireland). This subspecies is found in Ireland in the limestone pavements of the Burren in Clare and South-east Galway. It differs from the subspecies semele as follows:
1. The upperside is relatively light, inclining to grey rather than brown, with ill-defined marginal bands.
2. The male upperside has a greatly reduced androconial spot on the forewings.
3. The underside is paler, appearing very light with a greyish ground colour.
Hipparchia semele ssp. clarensis (de Lattin, 1952)
A series of Irish specimens from Co. Clare is different at the first glance from all the other races of this species by reason of its very divergent males. Irish males and females on the whole are richer and redder brown on the upperside, and on the underside have the black lines deeper black, and look richer in general, than English ones. But in ssp. clarensis the ground colour of the upper side is relatively light with a quite apparent incline to grey, contrary to insects from England and Germany which show a ground colour of a more pronounced brown; the very pallid marginal band is so much dusted with dark scaling that it is very ill defined from the dark proximal part of the wing. The hindwings are in general altered in a similar way, only the marginal band is more distinctly defined and shows the brick-red triangular spots on its distal part strikingly small and pale. But the most apparent characteristic of this subspecies is the great reduction of the androconial spot on the forewings of the male, this spot being relatively large in the typical form, extending from the analis to the end of the cell as an oblique band. In the Irish specimens from Co. Clare this band is confined to a few remains in the region of the lower cell border, so that at first sight one gains the impression that the androconial spot is entirely lacking. The under side has also a paler ground colour and therefore appears very light, this impression being enhanced by the broad milky white distal edging of the postmedian line, which is only relatively little dusted with dark scales. The female is differentiated more or less the same as the male, yet the difference is not so sharp because the androconial difference is lacking; from its neighbouring English and Continental populations it can be best distinguished by its strikingly greyish ground colour.
Holotype: 1 male, Co. Clare, 18.7.1926. L. A. E. Sabine coll. Allotype: 1 female, Co. Clare, 19.7.1926. L. A. E. Sabine coll.Paratypes: 1 male 3 females, Co. Clare, 18/19.7.1926. L. A. E. Sabine coll.All these specimens are contained in the collection Pfeiffer, München.[In the Zoological Museum at Tring we have 2 males and 2 females from Co. Clare. The androconial streak, which Dr. de Lattin stresses, varies a good deal in size in both English and Irish males from other counties, but on the average it appears to be about the same in both. In the 2 Clare males at Tring it is greyer and less conspicuous, but not actually smaller. These two males are certainly greyer on the upper side than any others from the British Isles, and the under side is pale. The females can be matched by aberrant examples from other places, but if all Clare examples are alike they cannot be matched by a series from elsewhere. I think Dr. de Lattin is dealing with a local race peculiar to the limestone Burren and associated with the pale ground there, which may be considered a subspecies. - E.A.C.]
Adults generally emerge at the start of July, peaking at the end of the month. The colonies found on the Great Ormes Head in north Wales, where individuals are much smaller in size than other colonies and are a distinct subspecies, emerge much earlier than at other sites - often at the beginning of June. This butterfly has one generation each year.
Hipparchia semele ssp. semele
Hipparchia semele ssp. thyone
Hipparchia semele ssp. scota
Hipparchia semele ssp. atlantica
Hipparchia semele ssp. hibernica
Hipparchia semele ssp. clarensis
The chart(s) above have been correlated with the phenology plot below, taken from the UK Butterfly Monitoring Scheme. The blue line gives average counts over the full data set from 1976 to date, and the red line gives the average for the last year.
This butterfly is found on sheltered, sunny and dry sites where vegetation is sparse, providing the bare ground that this butterfly requires. Typical sites include heathland, sand dunes, coastal grassland and disused quarries.
The male is more-often seen than the female and is territorial, usually perching on the bare ground that typifies their habitat or, occasionally, on a tree trunk or boulder. The male flies up to investigate any passing object and, if he encounters a female, the two will land on the ground. The male lands immediately behind her before moving around to face her head on. An unreceptive female will flutter her wings while a virgin female will remain still, encouraging the male to perform an elaborate courtship.
He starts by flicking his wings upward to reveal the orange patches found on the underside of the forewings. He then flicks his wings open and shut for a short time before bowing to the female and slowly bringing his wings together, when the female's antennae are brought together over the sex brands found on the male's forewings, as the male returns to an upright position. The scent scales from the sex brands allows the male to seduce the female, allowing him to move behind the female who is then mated.
Unlike the territorial male, the female is most-often seen when egg-laying. Both sexes take nectar and will feed from a variety of plants, including Bell Heather, Thistle, Bramble and also Buddleia if found in the vicinity.
Eggs are laid singly on the foodplant, or on nearby ground debris. Isolated plants, surrounded by patches of bare ground, are preferred. Eggs are white when first laid, but gradually turn pale yellow in colour. Unlike the eggs of related species, the egg of a Grayling retains a uniform colour and does not develop brown blotches as it develops. This stage lasts between 2 and 3 weeks.
The larva feeds on the tender tips of grass blades after emerging and eventually hibernates while still small, in the 3rd instar, at the base of a grass tussock. Feeding resumes in the spring and mature larvae are nocturnal, retreating deep within the base of grass tussocks during the day. There are 4 moults in total.