Small Blue

Cupido minimus (kew-PY-doh MI-nim-uss)

Small Blue (m) Totternhoe Quarry, Beds; 2nd June 2010
Photo © millerd
 

Wingspan
18 - 27mm

Checklist Number
61.010

Family:LycaenidaeLeach, 1815
Subfamily:PolyommatinaeSwainson, 1827
Tribe:PolyommatiniSwainson, 1827
Genus:CupidoSchrank, 1801
Subgenus:CupidoSchrank, 1801
Species:minimus(Fuessly, 1775)

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Introduction

This is our smallest resident butterfly with a wing span that can be a little as 16mm. The sexes are similar in appearance, although the male upperside is almost black with a dusting of blue scales, whereas the female is more dark brown in colour. Both sexes have an underside that is silvery-grey in colour, and not unlike that of the Holly Blue. This butterfly has a large distribition, being found from northern Scotland to the south of England, with colonies also in Wales and Ireland. However, outside of its strongholds in the south of England, colonies are often isolated pockets, typically in coastal locations. Most colonies consist of less than 30 adults, although a few colonies consist of thousands of adults. This butterfly is absent from the western and northern Scottish isles, the Isle of Man and the Channel Islands.

Cupido minimus

This species was first defined in Fuessly (1775) as shown here (type locality: Switzerland).

Small Blue - Bishops Hill, Warwickshire 17.05.2014

Male
Photo © Neil Freeman

Small Blue, Male, MHD, 28/07/2014

Male Underside
Photo © Pauline

Small Blue, female, Kithurst Hill, West Sussex, 9 June 2012

Female
Photo © Colin Knight

Small Blue - imago - Martin Down - 31-May-06 (0195)

Female Underside
Photo © Pete Eeles

Photo Album ...


Conservation Status

The population trend of this dainty butterfly is considered relatively stable, whereas the distribution trend shows a distinct decline, with the butterfly completely disappearing from some areas. For example, this species is now considered extinct in Northern Ireland with the last sighting in 2001. This species is therefore considered a priority species for conservation efforts.

UK BAP StatusDistribution Trend (%)Population Trend (%)
Priority Species
Click here to access the Biodiversity Action Plan (BAP) for this species.
Stable-4
Increase+31

The table above shows the distribution and population trends of species regularly found in the British Isles. The distribution trend represents a comparison between data for the periods 1995-1999 and 2005-2009. The information provided is taken from the Butterfly Conservation report The State of the UK's Butterflies 2011. The UK BAP status is taken from the UK Biodiversity Action Plan (UK BAP) (2007 review).

Habitat

Suitable sites for this species are those that are sheltered and contain a good amount of Kidney Vetch, together with grasses and shrubs which are used for perching and roosting. A wide variety of habitats is used, including unimproved chalk and limestone grassland, abandoned quarries, road and railway embankments and woodland rides and clearings.

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 appear in early May in southern sites, reaching a peak at the end of May and start of June. This butterfly has a partial second generation each year, except in northern Scotland.

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 spend a large amount of time basking or resting. Males perch on small shrubs or grass stems which they leave when investigating passing insects or when searching out nectar sources. They are not territorial, however, and can often be found in small groups of 2 or 3. Both sexes take nectar from various flowers, with Kidney Vetch, Bird's-foot Trefoil and Horseshoe Vetch being particular favourites. Males will also take salts and minerals from damp mud, animal droppings and carrion.

Virgin females entering the perching sites are quickly mated without any elaborate courtship. Once mated, the female spends most of her time searching out suitable plants on which to lay and, once found, she lays a single egg between 2 florets on the flower head. She then rubs her abdomen over the flower head which is believed to deter other females from laying on the same plant since the larvae are cannibalistic in their first instar.

Adults feed primarily on Bird's-foot Trefoil (Lotus corniculatus), Kidney Vetch (Anthyllis vulneraria) and Vetches (Vicia spp.).

Cupido minimus

Small Blue male - Addington, Surrey 1-June-2012

Photo © Vince Massimo
01-Jun-2012

Small Blue Female - Addington, Surrey 14-June-10

Photo © Vince Massimo
14-Jun-2010

Small Blue Male - Durlston CP, Dorset 22-May-08

Photo © Vince Massimo
22-May-2008

Small Blue - imago - Martin Down - 31-May-06 (0195)

Photo © Pete Eeles
31-May-2006

Small Blue pair (Second Brood) - MHD - 1st August - 2014

Photo © Maximus
01-Aug-2014

Small-Blue- 5D31888. Beds, May 2015.

Photo © IainLeach

Small Blue males - Brighton, Sussex 8-May-2011

Photo © Neil Hulme
08-May-2011

Small Blue, Male, MHD, 28/07/2014

Photo © Pauline
28-Jul-2014

Small Blues - Bishops Hill Warwickshire 26.05.2013

Photo © Neil Freeman
26-May-2013

Small Blue - imago - Martin Down - 22-May-09 (1)

Photo © Pete Eeles
22-May-2009

Small Blue Male (with heavy blue scaling) - Addington, Surrey 1-June-2012

Photo © Vince Massimo
01-Jun-2012

Small-Blue- 5D32035. Beds, May 2015.

Photo © IainLeach

Small Blue - imago - Martin Down - 10-May-05 (11)

Photo © Pete Eeles
10-May-2005

Small Blue, Kithurst Hill, West Sussex, 4 June 2012

Photo © Colin Knight
04-Jun-2012

Small Blue - imago - Martin Down - 30-Apr-07 (4)

Photo © Pete Eeles
30-Apr-2007

Small Blue - imago - Martin Down - 21-May-08 (2)

Photo © Pete Eeles
21-May-2008

Small Blue Male - Addington, Surrey 4-June-06

Photo © Vince Massimo
04-Jun-2006

Small Blue (m) Totternhoe Quarry, Beds; 2nd June 2010

Photo © millerd
02-Jun-2010

Small-Blue - Dunstable May 2013 5D32830

Photo © IainLeach

Small Blue male - Bishops Hill Warwickshire 09.06.2012

Photo © Neil Freeman
09-Jun-2012

Photo Album ...


Ovum

Several eggs are occasionally found on the same inflorescence, although these will generally have been laid by different females. The eggs are quite easy to find at suitable sites, and hatch in 1 to 3 weeks depending on temperature.

Small Blue - ovum - Martin Down - Unknown Date (2) [Tim Norriss]

Photo © Tim Norriss

Small Blue - ovum - Martin Down - Unknown Date [Tim Norriss]

Photo © Tim Norriss

Small Blue Ovum - Eyemouth, Scottish Borders - May 2010

Photo © NickMorgan

Small Blue - ovum - Solalex, Gryon, Switzerland - 09-Jul-11

Photo © Pete Eeles

Small Blue - ovum - Solalex, Gryon, Switzerland - 09-Jul-11-1

Photo © Pete Eeles

Small Blue - ovum - Solalex, Gryon, Switzerland - 09-Jul-11-8

Photo © Pete Eeles

Small Blue - ovum - Magdalen Hill Down - 26-Jun-12

Photo © Pete Eeles

Small Blue - ovum - Magdalen Hill Down - 26-Jun-12-1

Photo © Pete Eeles

Small Blue ovum - Found at Durdle Door, Dorset - 16.06.14

Photo © Tony Moore
18-Jun-2014

Small Blue ova, Magdalen Hill Down, 27/05/2015

Photo © Pauline
27-May-2015

Small Blue ovum, Magdalen Hill Down, 27/05/2015

Photo © Pauline
27-May-2015

Small Blue - ovum - Magdalen Hill Down - 11-Jun-15-5

Photo © Pete Eeles
11-Jun-2015

Small Blue - ovum - Magdalen Hill Down - 11-Jun-15-6

Photo © Pete Eeles
11-Jun-2015

Small Blue - ovum - Magdalen Hill Down - 11-Jun-15-7

Photo © Pete Eeles
11-Jun-2015

Small Blue - ovum - Magdalen Hill Down - 11-Jun-15-8

Photo © Pete Eeles
11-Jun-2015

Small Blue - ovum - Magdalen Hill Down - 11-Jun-15

Photo © Pete Eeles
11-Jun-2015

Photo Album ...


Larva

The newly-hatched larva is less than 1mm in length and immediately burrows into a floret where it feeds on the developing seed. As the larvae grow they start to feed outside the floret with their head buried deep inside, with their back end exposed. The larva hibernates on the ground, often under moss or in a crevice in the soil. The larvae emerge in the spring and, without feeding further, wander off to find a suitable pupation site. There are 3 moults in total.

The primary larval foodplant is Kidney Vetch (Anthyllis vulneraria).

Small Blue - larva - Stockbridge Down - 24-Jul-88 [Tim Norriss]

Photo © Tim Norriss

Small Blue larvae being attended by the ant Lasius niger, near Burnmouth Berwickshire, Scotland. 21st July, 2011.

Photo © IAC

Small Blue - larva - Magdalen Hill Down - 11-Jul-12

Photo © Pete Eeles

Small Blue - larva - Magdalen Hill Down - 15-Jul-12

Photo © Pete Eeles

Small Blue - larva - Magdalen Hill Down - 21-Jul-12

Photo © Pete Eeles

Small Blue larva - Caterham, Surrey 2-Aug-2012 L1

Photo © Vince Massimo
02-Aug-2012

Small Blue larva - Caterham, Surrey 2-Aug-2012 L1

Photo © Vince Massimo
02-Aug-2012

Small Blue larva - Caterham, Surrey 2-Aug-2012 L1

Photo © Vince Massimo
02-Aug-2012

Small Blue larva - Caterham, Surrey 2-Aug-2012 L1

Photo © Vince Massimo
02-Aug-2012

Small Blue larva - Caterham, Surrey 2-Aug-2012 L1

Photo © Vince Massimo
02-Aug-2012

Small Blue (hibernating larva) - Caterham, Surrey 13-Aug-2012 L1

Photo © Vince Massimo
13-Aug-2012

Small Blue (hibernating larva) - Caterham, Surrey 13-Aug-2012 L2

Photo © Vince Massimo
13-Aug-2012

Small Blue (hibernating larva) - Caterham, Surrey 6-March-2013 L2

Photo © Vince Massimo
06-Mar-2013

Small Blue (post-hibernation larva) - Caterham, Surrey 28-May-2013 L2

Photo © Vince Massimo
28-May-2013

Small Blue larva, Magdalen Hill Down, 22/07/2015

Photo © Pauline
22-Jul-2015

Small Blue larva, Magdalen Hill Down, 22/07/2015

Photo © Pauline
22-Jul-2015

Small Blue larva, Magdalen Hill Down, 22/07/2015

Photo © Pauline
22-Jul-2015

Small Blue - larva - Magdalen Hill Down - 10-Jul-15

Photo © Pete Eeles
10-Jul-2015

Small Blue - larva - Magdalen Hill Down - 18-Jul-15

Photo © Pete Eeles
18-Jul-2015

Photo Album ...


Pupa

The pupa is attached to a grass blade, leaf, or other vegetation, where it is attached to a silk pad by a silk girdle and the cremaster. This stage lasts between 1 and 3 weeks, depending on temperature.

Cupido minimus - Pupa [Wolfgang Wagner]

Photo © Wolfgang Wagner
www.pyrgus.de

Photo Album ...


Aberrations

Description to be completed.

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

Similar Species

Holly Blue

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
Fuessly (1775) Fuessly, J.K. (1775) Verzeichniss Der Ihm Bekannten Schweizerischen Insekten.
Leach (1815) Leach (1815) In Brewster: The Edinburgh Encyclopaedia.
Schrank (1801) Schrank, F. (1801) Fauna boica. Durchgedachte Geschichte der in Baiern einheimschen und zahmen Thiere.
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.