There are four species of these beautiful Calopteryx damselflies belonging to the family Calopterygidae, in Europe, and two occur in Britain: the Beautiful and the Banded demoiselle (below). There are also a number of subspecies of each type. In this blog I am featuring a Spanish subspecies of Calopteryx virgo, called meridionalis, and Calopteryx splendens from Bedfordshire in England.
Demoiselles have quite complex courtship behaviours, where the male displays to the female, prior to the pair joining up in tandem. Depending on the species, the males display their gorgeous, purple/blue wing colours, and sometimes their abdomen colours, to the females, and finally they point out potential places where she might like to lay her eggs!
The females usually have clear (hyaline) wings (below) although some develop male (androchrome) wing characteristics. The androchromes are thought to be male mimics, mimics, which have adapted male colouration to try and escape the harassment of excessive male mating attempts.
The Calopteryx male damselflies establish territories along streams, at places that contain plant material at or near the water surface (see below), and territory owners court and mate with females that come to these sites to oviposit.
Both sexes engage in multiple matings. Suitable oviposition sites – emergent aquatic vegetation – are often in short supply, so males will have competed vigorously for their ownership. The females have a a pseudopterostigma, (not a true pterostigma) on their wings (below). The female Calopteryx virgo shown below has brown-tinted transparent wings.
Some females fly up in response to the male’s cross display (below), but most require at least a hovering courtship flight before leaving the stream with the male to copulate. The cross display is a preliminary courtship behaviour, which varies somewhat in duration, height (perched or hovering) and location, relative to the males’ territory.
Male calopterygid damselflies generally keep their wings closed and their abdomen raised when at rest, and attract females by displaying colourful patches – called ‘tail lights’ – on the underside of abdomen tip during courtship flights. Difficult to capture a photo of this behaviour!
Calopteryx virgo males are described as courting females with a hovering flight, whereas C. splendens males engage in more chasing behaviour.
When C. virgo females enter a male’s territory, the male drops down onto the water surface with his wings partly folded and turns the tip of the abdomen upwards to expose the underside. Again, no photo of this behaviour! But see here!
Male demoiselles habitually flick open their wings in display (below). Whether they are signalling to other males or to females (or both!), I am not sure.
Males also fly courtship arcs: bobbing up and down while moving in an arc around the female, facing her at all times. The durations and amplitudes of the arcs differ between species, and the overall length of courtship depends on the receptivity of the female: unreceptive ones spread their wings in a refusal display. Less than half of courtships result in successful copulations.
Copulation in calopterygid damselflies will usually only occur if the female is receptive, and willingly to allow the male to grasp hold of her on completion of courtship. However, forced copulations sometimes occur under conditions of high population density.
Capturing insect behaviour in a photograph is always challenging, and I only have some slightly blurred photographs in some cases, above. Room for improvement!
Cordero, A. & Andrés, J. A. (2002) Male coercion and convenience polyandry in a calopterygid damselfly. Journal of Insect Science, 2:14. https://doi.org/10.1093/jis/2.1.14
Córdoba-Aguilar, A., & Cordero-Rivera, A. (2005). Evolution and ecology of Calopterygidae (Zygoptera: Odonata): status of knowledge and research perspectives. Neotropical Entomology, 34(6), 861-879.
Gomez‐Llano, M. A., Bensch, H. M., & Svensson, E. I. (2018). Sexual conflict and ecology: species composition and male density interact to reduce male mating harassment and increase female survival. Evolution, 72(4), 906-915.
Guillermo-Ferreira, R., & Bispo, P. C. (2012). Male and female interactions during courtship of the Neotropical damselfly Mnesarete pudica (Odonata: Calopterygidae). acta ethologica, 15(2), 173-178.
Pajunen, V. I. (1966). Aggressive behaviour and territoriality in a population of Calopteryx virgo L.(Odon., Calopterygidae). Annales zoologici fennici, 3(3), 201-214.
Waage, J. K. (1973). Reproductive Behavior and Its Relation To Territoriality in Calopteryx maculata (Beauvois)(Odonata: Calopterygidae). Behaviour, 47(3-4), 240-256.
Waage, J. K. (1984). Female and male interactions during courtship in Calopteryx maculata and C. dimidiata (Odonata: Calopterygidae): Influence of oviposition behaviour. Animal behaviour, 32(2), 400-404.
Waage, J. K. (1988). Reproductive behavior of the damselfly Calopteryx dimidiata Burmeister (Zygoptera: Calopterygidae). Odonatologica, 17(4), 365-378.