Sunday, February 21, 2016

Exploring the diversity of odonates: Are we done?

Among the billions of life forms around us, odonates or dragonflies and damselflies have been occupying only a small fraction of it with around 6,000 species currently known to science. The systematic study of odonates began with the birth of Linnaean taxonomy in 1758 and biologists and naturalists have been describing odonates around the world and assigning names for these species. 
So, after the 257 years, where do we stand now? 
Naming a species is the basic requirement in order to truly appreciate it and conserve it. Without giving a name to a species you can not study it, assess it for its conservation value or even discuss it. As odonates are wonderfully colourful, attractive, active, usually diurnal and comparatively large bodied insects, one might think that we already know enough of them after centuries of systematic studies and exploration. 
However, questioning this view, 60 new species of odonates were described from the continent of Africa by a single paper authored by K. D. B. Dijkstra, J. Kippings and N. Mézière just at the end of 2015. If you think about the total number of odonates known from around the world, this has increased the number of species from around 1% single handedly. A very interesting fact regarding these discoveries is that all of them have been made in the field, not inside a lab while studying the molecules. And some of them were not made from remote jungles but from places no one has cared to look intentionally before. 
The important point is, if that many African species were yet unknown to science until the last year, how many undescribed species might be there in the other regions? Especially, in the hottest biodiversity hotspots around the globe, including Madagascar, Indo-Burma, Sundaland, Philippines, Atlantic forests in Brazil and Western Ghats/Sri Lanka. 
As a biologist working in Sri Lanka I am well aware that only seven new species and two new subspecies have been described from Sri Lanka since the year 2000. According to the odonata checklist published by K. A. Subramanian in 2014 and a recent paper by C. G. Kiran, S. Kalesh and K. Kunte, this number is only six species in the whole of India with only two in the Western Ghats.

So, are we done? No, not even close.

You can read the interesting facts about the new discoveries from Africa here. 

Bedjanič, M., van der Poorten, N., Coniff, K. and Salamun, A. 2014. Dragonfly Fauna of Sri Lanka: distribution and biology with threat status of its endemics. Pensoft, Sofia. 321 pp.

Kiran, C.G., S. Kalesh & K. Kunte (2015). A new species of damselfly, Protosticta ponmudiensis (Odonata: Zygoptera: Platystictidae) from Ponmudi Hills in the Western Ghats of India. Journal of Threatened Taxa 7(5): 7146–7151; 

Klaas-Douwe B. Dijkstra, Jens Kipping & Nicolas Mézière (2015). Sixty new dragonfly and damselfly species from Africa (Odonata). Odonatologica 44: 447-607.

Subramanian, K.A. (2014). A Checklist of Odonata of India. Zoological Survey of India, Kolkata.