White-legged Damselfly (Platycnemis pennipes)
These are known as one of the 'Blue Damselflies' of which Somerset has 7 species: Common, Variable, Azure, Blue-tailed, Red-eyed, Small Red-eyed and White-legged.  Identifying these species can be very complicated as they all have similar features and all have colour variations and changes in colour as they age. 
A slightly rarer and harder to find damselfly, also doesn't appear in such large numbers as some of the other species.
The key thing for both sexes is the significant white stripe down their legs and hence the name.
Males are blue and black damselflies.
Females are a pale greenish/yellowish colour with black markings.
Immature are white or a pink colour.

Male
Male
Male
Male
Male
Male
Male
Male
Male
Male
Male (Young)
Male (Young)
Male
Male
Female
Female
Female
Female
Female
Female
Female
Female
Female
Female
Female (Teneral / Newly Emerged)
Female (Teneral / Newly Emerged)
Want to See 
Harder to find these.
They like low-lying areas with slow-moving water, so the levels are the best places to look for them.

Especially Good
Langport (River Parrett / River Yeo) (End of May / June)

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