A good friend of mine worked on this project.
A Small Dragonfly Is Found to Be the World's Longest-Distance Flyer
Pantala flavescens can be found around the world from the tropics to mid-temperate zones. It is even seen on islands in the middle of the Pacific Ocean. They often breed in temporary pools and their nymphs go through rapid development from egg to adult.
They do not over-winter at the northern and southern extremes of their range. Rather, they migrate north and south and breed during the warm seasons and disperse as soon as they emerge as adults.
Their sister species,
Pantala hymenaea, also is a widely dispersed species, but to a lesser extent than
P. flavescens.
The paper can be found here:
A Global Population Genetic Study of Pantala flavescens
These dragonflies have some interesting adaptations to a life spent almost entirely on the wing. Their wings are larger in surface area than most dragonflies of similar length and body weight. They use this to their advantage by gliding on the wind for long distances rather than expending more energy flapping the wings.
The thorax is enlarged to contain more well-developed flight muscles. The legs are very thin and spindly compared to dragonflies that perch a lot. The abdomen is reduced in size. The eyes make up more of the surface area of the head than many other dragonflies. This would aid in flying in the dark and also with capturing prey and spotting mates at breeding sites. Territorial behavior is not seen at breeding sites and mating behavior is not seen when groups of males and females are away from breeding sites.
Sometimes large groups of
Pantala will be seen in feeding swarms and in migratory flights.
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