Dark Green Fritillary

Argynnis aglaja (ar-GIN-iss a-GLY-uh)

Dark-Green-Fritillary Bakewell, Derbys 11 May 2011- 03C3221
Photo © IainLeach
 

Wingspan
58 - 68mm

Checklist Number
59.019

Family:NymphalidaeRafinesque, 1815
Subfamily:HeliconiinaeSwainson, 1827
Tribe:ArgynniniSwainson, 1833
Genus:ArgynnisFabricius, 1807
Subgenus:MesoacidaliaReuss, 1926
Species:aglaja(Linnaeus, 1758)

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Introduction

The Dark Green Fritillary is the most widespread fritillary found in the British Isles and is a pleasure to see as it flies powerfully over its grassland habitats, frequently stopping to nectar on Thistles and Knapweed. It gets its name from the green hue found on the underside of the hindwings, which are peppered with large silver spots. This butterfly can be found throughout the British Isles, although it is less common in central and eastern England. Outside of central Scotland and southern England, it is most frequently found in coastal areas and is the only fritillary found in Orkney and the Outer Hebrides. Despite its powerful flight, it is somewhat surprising that this species is not particularly mobile, staying within its breeding grounds.

Taxonomy Notes

Historically, several authorities have referred to f. scotica, defined in Watkins (1923), that is not recognised in current taxonomy. This form differs from the nominate form in that individuals are larger in size have much heavier black markings on both upper and undersides, especially in the female, and the underside has a darker green flush, with more prominent silver spots on both fore and hindwings. Different authorities described different distributions of scotica. Dennis (1977) says "The most extreme development of the morph is found in the Outer Hebrides, especially on Pabbay (Barra group), south Rona, north Raasay and on Orkney. Subspecies scotica has also been described by Heslop-Harrison for Scalpay, Soay, Rhum, Eigg, Canna and Coll, but everywhere in addition to specimens showing extreme development, others transitional to aglaia are found". The most recent analysis is given in Thomson (1980). Riley (2007) suggests that this form is found in Scotland (apart from southern localities), Ireland (where it is the only form found) and the Isle of Man. However, Riley's inclusion of Ireland is questioned by Nash (2012) who assigns all Irish specimens to ssp. aglaja. Thomson (1980), Emmet (1990), Riley (2007) and Nash (2012) elevate the aglaja forms to subspecific status. The counties where scotica was thought to be found, as mentioned by Thomson (1980), are shaded green in the image below.

Highslide JS

Argynnis aglaja

This species was first defined in Linnaeus (1758) as shown here (type locality: Sweden).

The nominate form is found throughout its range in the British Isles.

Dark-Green-Fritillary Bakewell, Derbys 26 June 2011- 03C5674

Male
Photo © IainLeach

Dark Green Fritillary (male) - Lullingstone Country Park, Eynsford, Kent 21-June-2015

Male Underside
Photo © Testudo Man

Dark Green Fritillary (female). Lullingstone, Kent. 3/7/16.

Female
Photo © Testudo Man

Dark Green Fritillary - Stockbridge Down - 2 July 2011

Female Underside
Photo © Clive

Photo Album ...


History

The table below shows a chronology of vernacular names attributed to this species. Any qualification of the name (e.g. male, female) is shown in brackets after the name.

YearNameReference
1700Great Sylver Spotted FritillaryBuddle (1700)
1742Darkened Green FritillaryWilkes (1742)
1766Dark Green FritillariaHarris (1766)
1795Silver-spotted FritillaryLewin (1795)
1803Dark Green FritillaryHaworth (1803)
1803Queen of England FritillaryHaworth (1803)
1832Charlotte ButterflyBrown (1832)

Conservation Status

Although this species has declined considerably since the 1970s, especially in eastern England, the butterfly remains our most widespread fritillary and is not considered a priority species for conservation efforts.

UK BAP StatusOccurrence Change
1976-2014 (%)
Abundance Change
1976-2014 (%)
Occurrence Change
2005-2014 (%)
Abundance Change
2005-2014 (%)
Not Listed
Decrease-33
Large Increase+186
Increase+44
Increase+18

The table above shows the occurrence (distribution) and abundance (population) trends, using information from The State of the UK's Butterflies 2015 (Fox, 2015). Any UK BAP status is taken from the UK Biodiversity Action Plan (UK BAP) (2007 review).

Habitat

The characteristic habitat of this butterfly is open, windswept calcareous grassland. However, in some areas it can also be found in woodland clearings and coastal dunes.

Distribution

 

Click here to see the distribution of this species or here to see the distribution of this species together with specific site information overlaid.

Life Cycle

Adults generally emerge in the middle of June, reaching a peak in early July. In northern Scotland, adults emerge a little later at the end of June, reaching a peak at the end of July and early August. There is one generation each year.

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.

 

Imago

Both sexes are avid nectar feeders and typically feed in early morning or late afternoon, when they will constantly fly from flower head to flower head staying at each flower for only a few seconds. This behaviour makes them very difficult to observe and it is sometimes easier to find a favourite flower and wait for a butterfly to come to you!

The males are the more conspicuous of the two sexes, and can be seen patrolling over large areas of habitat looking for a virgin female which often rest low down in vegetation. Once found, mating takes place almost immediately. A mating pair may be found resting on vegetation and will even continue to nectar while coupled.

Females are somewhat-easier to see when egg-laying, where they intersperse periods of nectaring with basking and bouts of egg-laying, when they will crawl deep in vegetation, searching out the lushest growths of larval foodplant before laying a single egg, although several eggs are often laid in the same area.

Adults feed primarily on Thistles (Cirsium spp. and Carduus spp.). Carline Thistle (Carlina vulgaris) and Knapweeds (Centaurea spp.) are also used.

Argynnis aglaja

Dark Green Fritillary (2m) 5.7.12 Whitbarrow, Cumbria. Downland boy

Photo © downland boy
05-Jul-2012

Dark-Green-Fritillary Bakewell, Derbys 26 June 2011- 03C6205

Photo © IainLeach

Dark Green Fritillary - imago - Arnside Knott - 12-Jul-05 (5)

Photo © Pete Eeles
13-Jul-2005

Dark Green Fritillary, Male, 28/06/2012, Pitt Down

Photo © Pauline
28-Jun-2012

Dark-Green-Fritillary Bakewell, Derbys 26 June 2011- 03C6387

Photo © IainLeach

Dark Green Fritillary Female - Arnside Knott, Cumbria 9-July-07

Photo © Vince Massimo
09-Jul-2007

Dark Green Fritillary male - Botany Bay, Sussex 7-July-2012

Photo © Neil Hulme
07-Jul-2012

Dark Green Fritillary female - Arnside Knott 30.07.2012

Photo © Neil Freeman
30-Jul-2012

Dark Green Fritillary - male - Arnside Knott - 19-Jun-14-4

Photo © Pete Eeles
19-Jun-2014

Dark Green Fritillary male - Arnside Knott, Cumbria 12-July-2012

Photo © Neil Hulme
12-Jul-2012

Dark-Green-Fritillary Bakewell, Derbys 11 May 2011- 03C3339

Photo © IainLeach

Dark Green Fritillary female - Arnside Knott, Cumbria 9-July-09

Photo © Vince Massimo
09-Jul-2009

Argynnis aglaja, Dunsford Wood, Devon 24-June-2008

Photo © m_galathea

Dark Green Fritllary - female - Martin Down - 10-07-2014

Photo © Wurzel

Dark-Green-Fritillary Bakewell, Derbys 26 June 2011- 03C5674

Photo © IainLeach

Dark-Green-Fritillary Bakewell, Derbys 26 June 2011- 03C6285

Photo © IainLeach

Dark Green Fritillary pair - Arnside Knott, Lancs. 9-July-07

Photo © Vince Massimo
09-Jul-2007

Dark Green Fritillary closer up - Martin Down, 16-07-2013

Photo © Wurzel
16-Jul-2013

Dark Green Fritillary (female). Lullingstone, Kent. 3/7/16.

Photo © Testudo Man
Dark Green Fritillary (female). Lullingstone, Kent. 3/7/16.

Dark Green Fritillary, female, 15/07/2013, Farley Mount

Photo © Pauline
15-Jul-2013

Photo Album (57 photos) ...


Ovum

Eggs are laid either directly on the foodplant, or on a suitable platform nearby, such as a twig, grass stem or dead leaf. Eggs are yellow when first laid but turn a dark purple after a few days and, eventually, a dark grey just before the larva emerges. This stage lasts between 2 and 3 weeks.

"The eggs are laid singly on various parts of the plant, mostly on the under side of the leaves and stalks. The egg is 1mm. high, of a conical form; the extreme summit is sunken, the base rounded at the edge, otherwise flat. There are from nineteen to twenty-two longitudinal keels, greatly varying in length; some commence at the summit and run to the base, others at different intervals from the summit, but all run to the base and disappear just before reaching it. The keels are prominent and stand out in bold relief; the spaces between the keels are transversely ribbed (about twenty in number), which are most prominent near the summit. At first the colour is a pale primrose-yellow, which gradually deepens a little, and when five days old it is banded with lilac-purple and pale greenish-yellow, the lilac colouring occupying the greater part of the upper half, and a mottled zone near the base; it very gradually deepens in colour on approaching emergence, and when fifteen days old the summit is very dark purple and the central yellow zone is more ochreous; just before emergence the crown is dusky-brown and the remainder a light pearl-grey. The eggs commenced hatching August 12th, 1892, remaining seventeen days in the egg state. The last eggs hatched on August 18th, 1892." - Frohawk (1924)

Dark Green Fritillary - ovum - Unknown location - Unknown date (2) [REARED] [Reg Fry]

Photo © Reg Fry

Dark Green Fritillary - ovum - Unknown location - Unknown date [REARED] [Reg Fry]

Photo © Reg Fry

DGF ovum, 1 day old, Oxenbourne Down, 27/07/2016

Photo © Pauline
27-Jul-2016

DGF ovum, 3 days old, Oxenbourne Down, 29/07/2016

Photo © Pauline
29-Jul-2016

DGF ovum, 3 days old, Oxenbourne Down, 29/07/2016

Photo © Pauline
29-Jul-2016

DGF ovum, 9 days old, Oxenbourne Down, 03/08/2016

Photo © Pauline
03-Aug-2016

DGF ovum, 9 days old, Oxenbourne Down, 03/08/2016

Photo © Pauline
03-Aug-2016

DGF ovum, 15 days old, Oxenbourne Down, 09/08/2016

Photo © Pauline
09-Aug-2016

Dark Green Fritillary - ovum - Thatcham - 07-Jul-17 [REARED]-4

Photo © Pete Eeles
07-Jul-2017

Dark Green Fritillary - ovum - Thatcham - 09-Jul-17 [REARED]

Photo © Pete Eeles
09-Jul-2017

Dark Green Fritillary - ovum - Thatcham - 15-Jul-17 [REARED]-2

Photo © Pete Eeles
15-Jul-2017

Dark Green Fritillary - ovum - Thatcham - 15-Jul-17 [REARED]

Photo © Pete Eeles
15-Jul-2017

Photo Album (12 photos) ...


Larva

The larva eats the eggshell on hatching and immediately enters hibernation in a curled up leaf or other piece of debris. The larva emerges in the spring and starts to feed on the tenderest new growth of the foodplant, either eating large chunks out of the leaf lobes, or eating the leaf entirely with the stem left standing. The larva is most active during sunny periods and can often be seen wandering across bare ground or short turf in search of the foodplant. The mature larva has a distinct colouring, being mostly black with a feint yellow band running down its back and a series of red spots running down each side. There are 5 moults in total.

The primary larval foodplants are Common Dog-violet (Viola riviniana), Hairy Violet (Viola hirta) and Marsh Violet (Viola palustris).

Dark Green Fritillary Larva

Photo © Trev Sawyer
Dark Green Fritillary Larva

Dark Green Fritillary - larva - Waxham Dunes - 15-May-2005 [Francis Farrow]

Photo © Francis Farrow

Dark Green Fritillary - larva - Thatcham - 22-May-12 (2) [REARED]

Photo © Pete Eeles

Dark Green Fritillary - larva - Thatcham - 22-May-12 (3) [REARED]

Photo © Pete Eeles

Dark Green Fritillary - larva - Thatcham - 17-Jun-13 (3) [REARED]

Photo © Pete Eeles
17-Jun-2013

Dark Green Fritillary - larva - Thatcham - 17-Jun-13 (4) [REARED]

Photo © Pete Eeles
17-Jun-2013

Dark Green Fritillary Larva - Debdon Forest, Northumberland 06-05-2014

Photo © Graham Beckwith
06-May-2014

Dark Green Fritillary Larva - Debdon Forest, Northumberland 06-05-2014

Photo © Graham Beckwith
06-May-2014

Dark Green Fritillary Larva - Debdon Forest, Northumberland 06-05-2014

Photo © Graham Beckwith
06-May-2014

Dark Green Fritillary (01) (early instar larva on violet) 7.5.15 nr.Beachy Head, East Sussex

Photo © downland boy
07-May-2015

Dark Green Fritillary (02) (early instar larva on violet) 7.5.15 nr.Beachy Head, East Sussex

Photo © downland boy
07-May-2015

Dark Green Fritillary - Larva - 06-05-15 - Dorset [REARED]

Photo © Coopera

Photo Album (12 photos) ...


1st Instar

"The larva directly after emergence is 2.12 mm. long; it is rather stout in proportion, very sluggish in its movements and rolls into a ring when touched. The colour is pale ochreous, with a darker ochreous sub-dorsal area, and a similar coloured band on the ventral surface just above the claspers. There are eight longitudinal rows of shining black warts, each bearing a long hair; those on the dorsal surface are long, moderately thick, and terminate in a slight knob and are serrated throughout; each wart is situated on a brown disc. All the dorsal hairs curve forward and are of a deep amber colour. The two central dorsal rows of warts are united at their base, the anterior one is the smallest, and the hair only half the length of the posterior one. The warts forming the sub-spiracular series are four in number on each segment, three are united and the fourth nearly so; these each bear a straight, finely pointed, serrated hair directed downwards, excepting the one immediately below the spiracle, which is slightly upturned; a few other smaller hairs occur on the ventral surface. The head is black and covered with a number of paler warts and hairs, similar to those on the body. The legs are black and ochreous and the claspers pale ochreous. On the first segment is a dark brown, coronet-shaped dorsal blotch. The larvae enter into hibernation immediately after leaving the egg, therefore they feed on nothing (except the portion of the egg-shell which they eat out to emerge) until after hibernation. Towards the end of March, 1893, the larva awoke from hibernation, and commenced feeding on the younger leaves of dog violet on the 28th, thus living without food for 228 days." - Frohawk (1924)

Dark Green Fritillary - larva - Unknown location - Unknown date [REARED] [Reg Fry]

Photo © Reg Fry

Dark Green Fritillary - L1 - Thatcham - 19-Jul-17 [REARED]-6

Photo © Pete Eeles
19-Jul-2017

Dark Green Fritillary - L1 - Thatcham - 07-Aug-17 [REARED]

Photo © Pete Eeles
07-Aug-2017

Photo Album (3 photos) ...


2nd Instar

"The first moult took place on April 9th, 1893. Soon after it measures 3.2 mm. in length. The ground colour is an ashy-grey with a slight ochreous tinge. There are six longitudinal rows of shining black spines, each furnished with a number of black spinelets; the greyish ground colour between the rows gives the larva a striped appearance; the spines are sub-dorsal, super-spiracular and sub-spiracular; the latter are situated on an ochreous stripe; the medio-dorsal grey stripe is conspicuous and is finely divided by a darker line. The head is black and shining, beset with warts and black hairs. Just before second moult it is 4.8 mm. long." - Frohawk (1924)

3rd Instar

"The second moult occurred on April 21st, 1893, remaining twelve days in second stage. After the second moult the colours are more clearly defined, the grey ground colour being replaced by white, forming longitudinal white stripes; the sub-spiracular band is composed of a large circular blotch of pale amber i colour on each segment, in the centre of each is a spine; in other respects it is similar to previous stage. When fixed for third moult it measures 7.6 mm. in length. For moulting the larva spins a thin web of silk upon the under surface of the leaf and thereon fixes itself for the process (at each moult)." - Frohawk (1924)

4th Instar

"The third moult was on April 28th, 1893, the third stage lasting seven days. After the third moult it measures 12.7 mm. long. The ground colour is deep lilac-grey. The sub-dorsal and super-spiracular spines are situated on black longitudinal bands. Below the lateral series of spines, which have orange-tawny bulbous bases, there is a dilated lateral stripe of a cream colour; this is sharply defined against the deep olive colour of the under surface; the segmental divisions are clearly defined by fine white bands; the sides are also checkered with white markings; in other respects it is the same as the previous stage. The larva are active in the sunshine, when they feed and bask in its warmth; in the shade they remain quiet. If disturbed they run with great activity. Frequently after feeding they crawl from the plant into the open and there bask in the sun, or else lie at full length on the upper surface of the leaves fully exposed to the sunshine." - Frohawk (1924)

5th Instar

"The fourth moult took place on May 5th, 1893, the fourth stage also occupying seven days. Four days after the fourth moult it measures 16 mm. long while at rest. Excepting the general colouring, which is deeper, and the lateral series of orange spots are now deep orange, the whole of the larva appearing much darker, it is similar to the former stage." - Frohawk (1924)

6th Instar

"The fifth and last moult occurred on May 15th, 1893, remaining ten days in the fifth stage. After fifth moult, fully grown, it measures 38 mm. in length. The head is narrower than the first segment; the body tapers at each end, especially the anterior. There are six longitudinal rows of spines, which are placed sub-dorsally, super-spiracular and sub-spiracular, from the fourth to eleventh segments inclusive. On the third segment in place of the sub-spiracular spines are warts only; the first two super-spiracular spines are situated between the segments and lower down than the rest. The anal segment has only four spines, and it terminates in a blunt conical point. All the spines and warts are shining black, and covered with sharply pointed, stiff spinelets. The ground colour of the dorsal surface is velvety-black, shading into purple-brown on the sides and ventral surface. It is slightly speckled with ashy-white; the segmental divisions are plainly defined by a series of transverse ashy-white marks; on each segment from the fourth to eleventh inclusive is a fairly large deep orange blotch adjoining the sub-spiracular spine. The head is dull olive-black, rather thickly covered with short and long hairs; the legs are black and finely haired, the claspers black and ochreous. The larvae feed by day, especially during sunshine, and are very active, and when disturbed run very rapidly. The larva above described (the same individual all through) spun up for pupation on May 29th, 1893, and pupated on June ist, remaining fourteen days in the last stage." - Frohawk (1924)

Dark Green Fritillary - larva - Thatcham - 28-May-06 (0142) [REARED]

Photo © Pete Eeles
28-May-2006

Dark Green Fritillary - larva - Thatcham - 28-May-06 (0143) [REARED]

Photo © Pete Eeles
28-May-2006

Dark Green Fritillary - larva - Thatcham - 09-Jun-12 (1) [REARED]

Photo © Pete Eeles

Dark Green Fritillary - larva - Thatcham - 17-Jun-13 (1) [REARED]

Photo © Pete Eeles
17-Jun-2013

Dark Green Fritillary - larva - Thatcham - 17-Jun-13 (2) [REARED]

Photo © Pete Eeles
17-Jun-2013

Dark Green Fritillary larva, Near Noar Hill, 19 May 2015

Photo © Pauline
19-May-2015

Dark Green Fritillary - L6 - Thatcham - 22-May-17 [REARED]

Photo © Pete Eeles
22-May-2017

Photo Album (7 photos) ...


Pupa

The larva creates a loose tent by drawing together several leaves and other pieces of vegetation together. The pupa is formed upside down, secured to the top of the tent by the cremaster. This stages lasts between 3 and 4 weeks, depending on the weather.

"The pupa is 19 mm. long, exclusive of the terminal segments, which are abruptly curved under, and 8.5 mm. wide across the middle (lateral view), its greatest diameter. Lateral view: The head is rounded; the thorax is lobed and keeled dorsally, and strongly concave between the thorax and abdomen; the second abdominal segment rises abruptly; the abdomen is acutely curved, so much so that the anal segment almost touches the apex of the wings; the latter are rather bulging along the costal margin, and keeled along the inner margin. Dorsal view: The head is tri-lobed in front, the base of the wings angular and projecting, and the basal half of the inner margin is convex, then sunken, and the abdomen is swollen at the fourth segment and then tapering. There are two sub-dorsal rows of small conical points running the entire length of the pupa: the first pair on the head, the second on the thorax, and a pair on each abdominal segment, and on the third, fourth and fifth segments are very much smaller super-spiracular points. The ground colour is ochreous on the head, thorax and wings; the abdomen is tawny or orange-ochreous. The head and thorax are heavily blotched with brown-black, and a large triangular patch of the same colour spreads over the greater area of the apical half of the wings; the anal segment is black and the next is almost so; the spiracles are surrounded by black, and deep purplish-brown blotches encircle the body at each segmental division, and the ochreous colouring of the wing is reticulated with the same dark colour; the legs are mottled and very finely reticulated with black and ochreous. The anal segment is shining, but the rest of the pupa is less so. The general colouring of the pupa has exactly the appearance of being scorched or burnt. It is attached by the cremastral hooks to a pad of silk spun on the stem of a plant or leaf stalk, with the surrounding leaves or stems drawn together, forming a tent-like shelter. The above is a description of the pupa, when six days old. The imagines emerged at the end of June and beginning of July, 1893." - Frohawk (1924)

Dark Green Fritillary - pupa - Thatcham - 09-Jun-06 (0234) [REARED]

Photo © Pete Eeles
09-Jun-2006

Dark Green Fritillary - pupa - Thatcham - 29-Jun-13 (1) [REARED]

Photo © Pete Eeles
29-Jun-2013

Dark Green Fritillary - Pupa - 22-05-15 - Dorset [REARED]

Photo © Coopera
22-05-2015

Dark Green Fritillary pupa, (reared) Liphook 30/05/2015

Photo © Pauline
30-May-2015

DGF larva, reared, 19/06/2015

Photo © Pauline
19-Jun-2015

Photo Album (5 photos) ...


Aberrations

Description to be completed.

Click here to see the aberration descriptions and images for this species.

Similar Species

High Brown Fritillary

The Dark Green Fritillary and High Brown Fritillary are most easily distinguished by their undersides, since only the High Brown Fritillary has a row of "ocelli" just inside the outer margin. In addition, as the name suggests, the High Brown Fritillary has a predominately brown hue to the underside, whereas the Dark Green Fritillary is predominately green.


Dark Green Fritillary (left) and High Brown Fritillary (right)

It is much more difficult to distinguish the Dark Green Fritillary from the High Brown Fritillary based on their uppersides. However, the first row of dots from the outside edge of the forewing upperside do give a clue - the 3rd dot from the apex of the forewing is in line with the other dots in the Dark Green Fritillary, but indented toward the body in the High Brown Fritillary.


Dark Green Fritillary (left) and High Brown Fritillary (right)

Queen of Spain Fritillary

Description to be completed.

Silver-washed Fritillary

Description to be completed.

Videos


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The following links provide additional information on this butterfly.

References

The species description provided here references the following publications:

ReferenceDetails
Brown (1832) Brown, T. (1832) The book of butterflies, sphinxes and moths.
Buddle (1700) Buddle, Revd. A. (1700) [Herbarium, preserved in the Botany department of the Natural History Museum, London].
Dennis (1977) Dennis, R.L.H. (1977) The British Butterflies - Their Origin and Establishment.
Emmet (1990) Emmet, A.M. and Heath, J. (1990) The Moths and Butterflies of Great Britain and Ireland.
Fabricius (1807) Fabricius, J.C. (1807) Magazin für Insektenkunde, herausgegeben von Karl Illiger.
Frohawk (1924) Frohawk, F.W. (1924) The Natural History of British Butterflies.
Harris (1766) Harris, M. (1766) The Aurelian. Edition 1.
Haworth (1803) Haworth, A.H. (1803) Lepidoptera Britannica.
Lewin (1795) Lewin, W. (1795) The Papilios of Great Britain.
Linnaeus (1758) Linnaeus, C. (1758) Systema Naturae. Edition 10.
Nash (2012) Nash, D., Boyd, T. and Hardiman, D. (2012) Ireland's Butterflies: A Review.
Rafinesque (1815) Rafinesque, C.S. (1815) Analyse de la nature ou Tableau de l'univers et des corps organisés.
Reuss (1926) Reuss, T. (1926) Systematischer Überblick der Dryadinae T. Rss. mit einigen Neubeschreibungen (Lep. Rhopal). Deutsche Entomologische Zeitschrift.
Riley (2007) Riley, A.M. (2007) British and Irish Butterflies: The Complete Identification, Field and Site Guide to the Species, Subspecies and Forms.
Swainson (1827) Swainson, W. (1827) A Sketch of the Natural Affinities of the Lepidoptera Diurna of Latreille. The Philosophical magazine : or Annals of chemistry, mathematics, astronomy, natural history and general science.
Thomson (1980) Thomson, G. (1980) The Butterflies of Scotland.
Watkins (1923) Watkins, H.T.G. (1923) A new Argynnis Race. The Entomologist.
Wilkes (1742) Wilkes, B. (1742) Twelve New Designs of English Butterflies.