Photo by Trevor Baker

Comma  Polygonia c-album (Linnaeus 1758 )  

 Family:  Nymphalidae, subgroup Nymphalinae (the “Nymphalids” or “Vanessids”)

Name Origin (Etymology) Polygonia, translated from latin is  "has manyl angles", refers to the very angular wings. The small C-shaped white comma, on the underside of the wings, has given it the latin name  c-album and in English the name, Comma. The Latin C derives from the 3rd letter of the greek alphabet "gamma" and "album" translated from latin means white 


The upperside  can look like a very tatty worn  Small Tortoiseshell, but with scalloped wings and a more even orange brown coloration and  lacks the blue spots its fairly easy to identify.  It can be confused with Silver-washed Fritillary which  flies in the same habitat.  The Comma’s undersides closely resembles a dried up leaf varying from dark brown to near black, with a marbling of ochre and bronze green, and the usually distinctive white C mark on the hindwing.  When seen, wings closed, on a dried bracken leaf everything makes sense as the mimicry with the scalloped edges and subtle marbling and colouration is perfection. Its no surprise that it is often seen in number where bracken abounds  in woodlands clearings.

Males and females are very similar, but females tend to be larger with less ragged edges and a more even dark coloration on the underside.  Up to half of the first brood have brighter, more golden orange upperparts and much paler underparts with less strongly scalloped wings. These are known as the hutchinsoni form, after Emma Hutchinson (b 1820/d 1906) who was first to breed them and discover that only this colour form produced the second brood. In July females can sometimes be seen searching and closely inspecting shoot tips of Elm branches with flight resembling an oversized White-letter hairstreak

Males establish territories aggressively investigating any species that come by,  sometimes causing a neighbouring male to spiral upwards in combat. The triuphant resident returns to his perch  Mating appears to take place unseen, high up in trees, perhaps at night. Many sources suggest it does not appear to migrate across areas of sea.  But  sightings on the Isle of Man and in Ireland, as well as a sighting 3.5km off the Cornish coast, and an occasional presence on the Isles of Scilly (Wacher et al 2003), suggest that sea crossings may be quite common.

Have you seen Hutchinsoni?

It can be noticeable in the last days of June many of the newly emerged Comma's you seeing are of the  pale, more golden form   As often as not you just see something very golden shoot past and I  must admit often confuse with Silver-washed Fritillary.  If your lucky enough to observe one nectaring or perched take a look at the 'tails' and colouration.

A variable proportion of the summer brood of Comma butterflies look, and behave differently from the rest. Known as the hutchinsonii form, they are a paler orange, with paler brown undersides too, and the projections on their wings are noticeably shorter than normal. But the really unusual thing is their behaviour. The "typical" Commas in the summer brood initially show no interest in mating, and feed up on nectar until late autumn before hibernating. They then sexually mature and mate in the spring after hibernation. Hutchinsoni butterflies mate straight away, then die, but produce a brood of "typical" offspring that emerge in autumn, and which hibernate and mate in the spring alongside butterflies that emerged at the same time as their parents (so about 3 months older). The appearance of hutchinsoni is largely governed by day length during the caterpillar stage.   They appear from mid-June into July (see explanation below)

Normal Dark Form  

With a dark underside and more pronounced 'tails'

Summer Pale Form 'Hutchinsoni'

With a pale underside brighter golden and short 'tails'

Habitat :    Woodland 

The species’ preferred habitat is sunny open woodlands, woodland rides, edges or clearings, or country lanes. The most widely used foodplant is Common nettle usually in partial shade. Other species used include Hops and Wych elms in Yorkshire but occasionally on Willow and Hazel. Circumstantial evidence suggests Wych Elm may be a  prefered foodplant where it occursObservations have been made in Northumberland and Durham where 50% of records have been specifically on Wych Elm (pers comm. Ian Waller).  Woods with more Elms tend to have larger populations of Comma.  Studies has shown that Elms are  the prefered  foodplant the further north you go but as temperatures rise survival rates on nettle are much  better.   

Status : Widespead and Common; Occupancy and Abundance increasing rapidly; a climate change winner with an all time high in 2023

Its distribution  has waxed and waned over the years corresponding to cooling/warming spells in our ever changing climate. It was well known in Yorkshire untill 1816 when biggest volcanic eruption ever by Tambura ment there was no summer  that year and almost all butterfly populations crashed.  Comma recovered strongly with a warm period in 1830's  up till the 1870's while spreading well up into Scotland  during this time. The UK population then crashed  after the Krakatoe  eruption and the following cold period 1879-1895 except  for Welsh border counties Gloucestershire and Hereford where it remained common in the counties hopyards. Hops were the prefered foodplant at this time,  however in Europe nettles are prefered.  It returned to Yorkshire in the warm period of the 1930 and 40's, and its foodplant changed to nettle suggesting that these might be europeans  taking advantage of the warming climate plus we know that nettles are favoured.  In the  later 50's and 60's it declined once again, as it became cooler reaching a modern day minimum in the mid 60's and was almost absent apart from early Autumn wanderers until about 1982 when the current expansion recommenced and continues at an ever increasing rate and in 2023  greatly outnumbered Small Tortoiseshell and even Peacock in the Vale of York to reach and all time high .  The contrast with Small Tortoiseshell is stark as that species  became almost absent in much of the Humberhead and south half of the Vale of York and  increasingly confined to cooler areas  above 100m during the current  run of hot summers. The Comma seems well adapted to deal with heat and this likely due to its flexability in producing a summer brood  which has become very difficult for Small Tortoiseshell which has been forced to hibernate in June.

World Status  

In the last decade it has crossed the channel and established in southern Ireland as well as now spreading up well into scotland reaching the great glen. Much of France and eastwards across Central Europe to south Finland, extremely local in north Spain. North Africa, and Asia. It is primarily a woodland butterfly, living in low-density forests in sunny spots and moist soil and usually occurs at low density. It is  most common in the woodland, country lanes, and garden areas of Norway, Sweden and UK.

Comma has been the fastest expanding UK species for some time  and in Yorkshire has nearly   doubled in occupation in the last 23 years as well ilustrated by the animated map above.  It also picks out their woodland  home areas of the limestone ridge, tabular hills and some of  river valleys  where it is the most abundant and a even lower level spread in the urban West and South Yorkshire. 

Abundance although dipping between 2006 and 2015 as many species did  due to a dip in temperatures was followed by a rapidly increasing trend with a run of warm years from 2017 with 2022 and 2023 being exceptional. An interesting contrast is  when Small Tortoiseshell boomed in the wet summers of 2020-21  Comma dipped to half  but then in the hot & dry early summers of 2022 and 23 Tortoiseshell collapsed while Comma boomed. What was the link?  We know that both Comma and Red admiral caterpilars are not only singular but also hide underneath leaves and make tents while gregarious caterpillars like the other vanessids who thermoregulate by getting closer together  may overheat in full sun.  In contrast Comma and Red admirals whose  singular larvae are at ambient temperature benefit a great deal more from a warming climate

Where and When to Find

In Spring you are most likely to find it in fair numbers in its favoured woodlands.  In particular Allerthorpe Common, Brockadale, Wykeham Causeway, Askham Bog and  Bishop Wood.  

Begins to emerge from hibernation in March and peaks in  late April but can be seen in lower numbers right through to the beginning of June. By the middle of June the first of the new generation begins with the hutchinsoni form in prominence  that peaks in mid July. The  slower developing regular dark form begins to emerge about 3 weeks after leading to a double hump you see in the flight curve and continuing till early August.  During this time there is much movement of the species away from its woodland home adults ranging widely through gardens or orchards in search of nectar plants and rotting fruit on which to feed up prior to hibernation.  They will also visit animal droppings, including half-dried dog faeces, probing for salts (pers obs.). The 2nd generation emerges in late Aug-Sept  and also ranges widely moving to nectaring on late flowers rotting  fallen fruit and Ivy flowers  while making their way back to their woodlands home  in late September/ October before hibernating quite often on tree branches.   Hibernated butterflies may awake on warm, winter days in Jan/Feb, and nectar on  Sallow ‘Pussy’ Willow  and other species of catkins, but the majority are more likely to emerge from early March onward.  As most Comma's hibernate and breed in woodland areas, they are not as evident in gardens in spring as they are in autumn. 

Life Cycle

The Comma spends most of its life pretending to be something else, larvae have a chalky stripe  half way down its back which makes it look uncanningly like the lime of a bird dropping while the adults underwings are practically indistinguishable from a dead leaf ; a master of mimicry. The Comma has a flexible life cycle, which allows it to capitalize on favourable weather conditions. The butterfly can be seen at any time of the year, occasionally awakening on warm winter days. The butterfly emerges from hibernation in March, giving rise to the next generation which appears between mid-June and start of July. 

Females lay 10 to 25 eggs on each suitable day, which hatch after 2 to 3 weeks and  after 3 black instars, become intrically marked in ginger and brown larvae have a white splodge with spines and rest tilted with its tail  up in the air making it look even more like pooh! at the final instar it looses the white stripe as it likely to moving longer distances to pupate and the mimicry wouldnt work.  

The 1st brood larval period lasts around 4 to 7 weeks depending on which colour form is involved; hutchinsoni being 3 weeks faster.  Pupae closely resemble withered leaves and hang from a pad of silk under a leaf or branch of the foodplant with a number of silver mirrors to indicate light shining through the dead leaf.

 Hibernation often takes place on tree trunks and branches, and occasionally in caves, hollows and open buildings.  The butterfly looks like a dead leaf with the comma mark appearing to be a crack in the leaf, whilst the white legs can merge into the mosaic of lichens found on the bark.

 Video of its life cycle in Poland. by Var Wild

Form Hutchinsoni

What causes Hutchinsoni?  

The proportion of the two forms seems to be determined by daylight length during the larval stage but also temperature and succulence of foodplant plays a part.  Food quality is important to all the vanessids; the more succulent the higher the fecundity while poor dry food wil cause death and inhibit  sexual maturity which triggers hibernation almost immediatly.   First brood larvae, which develop before the solstice, are likely to be hutchinsoni although you can still have hutchinsonni after the solstice if its very warm  and the nettles very succulent.  Those developing as daylength shortens after the solstice  grow more slowly and emerge 3 weeks later as the normal darker form whose prime purpose is to hibernate successfully in readiness to sexually mature and then mate the following spring. The proportion of hutchinsoni will vary from year to year according to weather conditions and latitude. An early emergence from hibernation is likely to increase chances of higher numbers of hutchinsoni as will a warm  May into June.  As one moves north or over 100m altitude (=1'C or 150 miles further north) the occurrence of a 2nd brood becomes more sporadic, and limited to exceptionally good summers. In contrast in most of southern europe  the majority of the 1st brood is hutchinsoni.  


Although major variation is rare, over 30 aberrations have been described.  Ground colour can vary considerably from almost white (ab albus Frohawk) or pale straw yellow (ab dilutus Frohawk), to examples where the dark markings join together (ab suffusa Tutt), or the hindwing is almost black (ab reichenstettenis Fettig).  The amount of ochre and metallic green on the underside may vary as can the ‘comma’ mark in size or shape.  More rarely it may even be missing (ab extincta Rebel).

Thanks for contributions by E Ingram