Contents ] GreenHairstreak ] BrownHairstreak ] PurpleHairstreak ] SmallCopper ] [ SmallBlue ] CommonBlue ] HollyBlue ]

small blue   <>   cupido minimus   <>   gormán beag


© DHardiman 2003  

Habitat:  The Small Blue, Ireland's smallest butterfly, is quite scarce and local in Ireland.  It is found on coastal sand dunes and calcareous ground inland.  Its only larval food plant is Kidney Vetch.  
It appears to be single brooded in Ireland.
Larval Food Plant:  Kidney Vetch  Anthyllis vulneraria
Flight Time:   End of May to early July
Hibernation:  Overwinters as a larva.
The upperwings of the male is smokey-black with a silvery-blue colour near the body and the female is dark bronze-brown.

On the underside the forewings of the male are pale pearly-grey in ground colour with silvery-grey near the body.  They have an outer series of  7 white-ringed black spots at the outer margins and a small white-ringed black bar more medially.  
The hindwings have a series of  9 white-ringed black spots in an irregular arc towards the outer margins.  There is also a white-ringed blach bar and two more white-ringed spots closer to the body on each hindwing.

The underside of the female has a ground colour tinged pale-ocherous, otherwise it is similar to the male.

It should be noted that there is considerable variation in the colour of this adult butterfly.
A pale grey form of the male var. pallida is occasionally seen.


Small Blue butterfly


                                                                                Life Cycle of  the Small Blue


The tiny blue disc shaped eggs measure c. 0.45 mm in diameter and are laid singly among the flower  buds of 
Kidney Vetch from about late May to the end of June and hatch in c. 10 days.  There may be two or three on 
each flowerhead, laid by different females.

Eggs deposited among the woolly calyxes of  Kidney Vetch. 
Eggs deposited among the woolly
calyxes of  Kidney Vetch.
                                  © DHardiman 2001


The fully grown larva is short and stout measuring up to 10 mm in length and tapering towards the extremities.
The body is pale ochreous and sometimes tinged with green.  It has a  brown mediodorsal line and a white,
sometimes pink tinged, line on each side below the level of the spiracles.  The small head is shiny black and
can be retracted  into the body.  The body is covered with setae.

Small Blue Larva on Kidney Vetch
 Small Blue full-grown larva well
 camouflaged on Kidney Vetch.
                                 © DHardiman 2001

The young larva bores into the flower to feed on the developing seeds,  it  will also eats  other larvae of
its own species encountered.  By mid-July the adult lives openly on the seedhead and is fully grown
by mid - late July.  At this stage it  enters diapause,  overwinters  and  pupates the following spring .
The overwintering larva emerges about mid-April to early June and pupates without further feeding.


The pupa is attached to a silk pad produced by the larva on a moss stem,  blade of grass,  leaf or in a soil crevice.
It is suspended from the pad by its cremasteral hooks and supported by a silk girdle.  Pupation lasts from 6-18
days, depending on the temperature.


The adult emerges, after the overwintering phase, in May to early July.


DHardiman 2004   




 Contents ]

 GreenHairstreak ] BrownHairstreak ] PurpleHairstreak ] SmallCopper ] [ SmallBlue ] CommonBlue ] HollyBlue ] 

Hesperidae ] Pieridae ] Lycaenidae ] Nymphalidae ] Satyridae ] Migrants ] .