Citrine Forktail

Citrine Forktail, Ischnura hastata
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Odonata
Suborder:	Zygoptera
Family:	Coenagrionidae
Genus:	Ischnura
Species:	I. hastata
Binomial name
Ischnura hastata (Say, 1839)

The Citrine Forktail, Ischnura hastata, is a damselfly of the family Coenagrionidae.

Physical description

This species is 20–27 mm in length, and its hindwing is 11–15 mm long; it is thus considerably smaller than most European members of the genus Ischnura.

Adult males have a black head and thorax, with blue markings, and a largely yellow abdomen, with black markings on its upper surface. The term citrine refers to its yellowish colouration. Adult females are initially largely orange, marked with black above on the head and rear part of the abdomen. They undergo a colour change, through brown or olive to greyish, as they mature.

Male Citrine Forktails are the only damselflies in the world with the pterostigma situated away from the leading edge of the wing.

Distribution

It is native to North and South America, although there is also a population on the Azores. The Azorean population is likely to have been present since the late 19th Century; however, it was not identified as this species until 1990.

Life history

In North America, this species has a typical dragonfly life-history. However, the population on the Azores reproduces by parthenogenesis, making it the only population of Odonata anywhere in the world to reproduce by this means — parthenogenesis is unknown in the species' American populations. ^[1]

In the southern United States, adults are on the wing year-round, while further north the flight-season is from April to November, and in the Azores from May to August.

Gallery

• 

  Another male

References

1. ^ Lorenzo-Carballa, M O; Cordero-Rivera, A (10 June 2009). "Thelytokous parthenogenesis in the damselfly Ischnura hastata (Odonata, Coenagrionidae): genetic mechanisms and lack of bacterial infection". Heredity 103 (5): 377–384. doi:10.1038/hdy.2009.65. 

• Dijkstra, Klaas-Douwe B. and Richard Lewington (2006) Field Guide to the Dragonflies of Britain and Europe British Wildlife Publishing

External links

• A photo page about Citrine Forktail
• Info and Photos at BugGuide