The Fauna of Sri Lanka - IUCN

The Fauna of Sri Lanka (2006)
endemic representatives to a total of 57 (47.5 %). Endemism is very high or almost exclusive in the
families Chlorocyphidae, Euphaeidae, Protoneuridae, Platystictidae, Gomphidae and Corduliidae (Fig. 1).
More than half of all endemic species are probably not closely related to the species occurring in India.
Some species, viz. Sinhalestes orientalis, Cyclogomphus gynostylus, Microgomphus wijaya and
Anisogomphus solitaris seem to be taxonomically isolated.
Figure 1: Endemism of dragonfly fauna of Sri Lanka. Total number of dragonfly taxa (grey columns) and
number of endemic dragonfly taxa (black columns), sorted by families.
To gain a better overview of the present knowledge of the dragonfly fauna of Sri Lanka all published data
for all species and subspecies were analysed in order to evaluate their research state. Also some of the
author’s unpublished data were included (Table 1). The analysis clearly shows that at present we know
very little about dragonflies of Sri Lanka. Most species in given categories are confined to Sri Lanka and
this fact definitely has also “global” importance from the biodiversity conservation point of view.
Category I: The species group known from one sex consists of only endemic taxa. Females are mostly
undescribed. The reason is that females are rarely seen at waters, their behaviour is less known, and they
are difficult to determine.
Category II: About one quarter of the species in Sri Lanka has been found on only a few localities and
the records are from a limited number of specimens. This category also consists of exclusively endemic
taxa. This information clearly indicates a poor faunistical research state of dragonfly fauna of Sri Lanka
and in some cases should not be interpreted as actual species rareness.
Category III: The group of species with unknown larval stages or larval skin, contains no less than 75
species and subspecies or more than 60 % of the odonate fauna of Sri Lanka. This information is important
because records of larvae and exuviae clearly indicate the development of the species in a particular habitat.
For the research of ecological requirements of individual species, which forms a basis for the effective
species conservation measures, the correct determination of larvae or exuviae is of crucial importance.
Category IV: Some species, e.g. Sinhalestes orientalis, Heliogomphus ceylonicus and Heliogomphus
nietneri, have not been found for more than 120 years since their original descriptions. All species in this
category appear rare and endangered or even extinct. They deserve special attention in the future.
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