T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Damselfly (Red) Xanthocnemis zealandica

Kingdom: Animalia 
Phylum: Arthropoda 
Class: Insecta 
Order: Odonata 
Family Coenagrionidae
Scientific name: Xanthocnemis zealandica
Common name: Red Damselfly, Red Coat Damselfly

The red damselfly is the most common damselfly found in a New Zealand. It is a native found throughout New Zealand. They are expert hunters - adults take small insects on the wing and their nymphs are pretty impressive aquatic predators. 
You can tell a damselfly from a dragonfly thanks to the way they hold their wings - damselflies fold them up over their body when they land while dragonflies hold them open.

The photo below is of a mating pair with a male onlooker. Copulation involves the male grasping the female behind the head with appendages on his abdomen.  She will then bends her abdomen underneath his thorax to recover a packet of sperm that he has placed there. Adults may be seen flying in this tandem position.



A female red damselfly (heterochrome coloured, there are two versions of their colouration) - 

An androchrome female. Androchrome refers to the colouring of a female whose colour scheme is similar to that of the male of the species. 


Female Xanthocnemis zealandica carrying water mites.  See text below photo.

Scientists Jose Andres and Adolfo Cordero of the Universidade de Vigo, Pontevedra, Spain, took a close look at parasitism in their research “Effect of Water Mites on the Damselfly, Ceriagrion tenellum,” published in a 2002 edition of Ecological Entomology.
They pointed out:
1. "Water mite parasitism is expected to have an important effect on damselfly survivorship and reproductive success because mites drain considerable amounts of body fluids from their hosts," they wrote in their abstract. "This study tests the effect of water mite parasitism in a marked population of the damselfly Ceriagrion tenellum during 1995 (individuals marked as mature adults) and 1996 (individuals marked as tenerals)."
2. "Almost all teneral individuals were parasitized (98%) and mites were aggregated strongly on some individuals. Parasite load increased during the season."
3. "Parasites had no effect on the probability of recapture of hosts as mature adults. The average daily survival rate of lightly- and heavily-parasitized individuals, estimated with Jolly's stochastic method, did not differ significantly."
4. "In 1995 parasites had a significant effect on host mating success. The probability of mating was about 25% lower for heavily parasitised males than for lightly parasitized males. Lightly parasitized males also mated more times than heavily parasitised males, even if heavily parasitized males lived longer. In 1996, parasitism did not have an effect on male mating success. In both years mites had no effect on female lifetime mating success."
In conclusion, they found that "water mite parasitism does not reduce damselfly survivorship, but it could reduce male mating success in some circumstances. Further long-term studies are needed, especially in populations with a lower incidence of parasitism."  

Thanks to Wikipedia for text and information http://creativecommons.org/licenses/by-sa/3.0/