Large Red Damselfly

Pyrrhosoma nymphula

Usually the first to emerge and not likely to be confused with anything else, seen as early as April some years but depends on the spring weather. Widespread and seen at most sites in varying numbers, but I find Thornley woods pond the best for observation and photographs, and had my latest record here of September 4th 2012.

Large Red Damselfly (mature male)
Often found perching openly from a vantage point to oversee their territory

Unmistakeable red abdomen tipped with black 

Close-up shows a cracking colour code, the eyes are like miniature
planets and the thorax is a superb combination of black, red and yellow. 

Large Red Damselfly (female)
Females have a much thicker abdomen than males and come in three
forms. This is the typica form showing two full black segments
in the second half of the abdomen, though is probably not yet fully mature
as the antehumeral stripes are yellow instead of red. 

This is the less common fulvica form, showing only one full black
segment in the second half of the abdomen.
 
The third and by far rarest form melanotum
Top of the abdomen is almost entirely black and will generally
show more yellow than red.


Immature individuals of both sexes contain a lot more yellow, and on average, the male takes 12 days to mature, the female 16, and sadly the mature individuals only live for another 5-7 days.

Teneral male\

Teneral female
Large Red Damselfly exuvia

Tandems are formed when a female wanders into a
territory held by a male. There is no courtship.

Copulation lasts 15-20 minutes then it's straight to the pond
for oviposition.

Unusually this female is ovipositing alone, it is
more usual to have the male still attached in
the sentinel position.

Eggs hatch after 2-3 weeks and larvae have a two year life-cycle. Larvae reaching their final stage in late summer lie dormant over their second winter, and lengthening days and rising temperatures trigger a synchronised emergence in early spring.

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