ZYvlAENA] 



ZYGAEN1DAE 



447 



Neuration of Zygaena trifolii. 



thickened from base to alxmt f or |, thence tapering to apex, 

 simple. Thorax densely hairy beneath. Abdomen hairy. 

 Femora more or less hairy beneath, 

 tibiae smooth - scaled, all spurs 

 present, short. Forewings : 8 and 

 9 stalked. Hindwings : 6 and 7 

 sometimes connate, upper margin 

 of cell angulated at connection. 



The genus is extensive, but con- 

 fined to Europe, N. and C. Asia, 

 Japan, and N. Africa, its range 

 coinciding exactly with the limits 

 of the Palaearctic region. Imago 

 with forewings elongate-triangular. 

 The species are very similar, often 

 interbreed, and are particularly 

 liable to form local races ; so that their study is excessively 

 difficult. The larvae are equally similar and variable. 



1. Forewings with upper basal spot reaching to be- 



yond J . .2. 



not reaching J 3. 



2. Forewings besides with four spots . 5. exulans. 



with two elongate blotches 6. pilosellae. 



3. Smaller, rather thinly scaled . . 4. meliloti. 

 Larger, not thinly scaled . . .4. 



4. Forewings six-spotted . . . \.filipendulae. 



five-spotted . . . .5. 



5. Termen of forewings slightly rounded, middle 



spots separate . 2. lonicerae. 

 ,, moderately rounded, middle 



spots usually confluent 3. trifolii. 



1. Z. filipendulae, L. 28-35 mm. Abdomen deep green or 

 indigo-blue. Forewings very deep green ; six deep crimson 

 spots, first pair subbasal, elongate, sometimes confluent, second 

 pair sometimes confluent, sixth sometimes small. Hindwings 

 deep crimson ; a slender green-blackish terminal streak ; cilia 

 blue-blackish. 



Britain to Caledonian Canal, Ireland, very common ; Europe, 

 Asia Minor, Syria ; 6, 7. Larva dull green ; a subdorsal series 

 of black transverse spots, one broader and one narrower on 

 each segment ; a lateral series of black crescentic or divided 

 spots ; between these two series a row of yellow marks ; head 

 black : on Trifolium, Lotus, Lathy rus ; 8-5. 



