Worldwide, there are 5,680 species of described Odonata (dragonflies and damselflies). A global sample of 1,500 species of dragonflies and damselflies was included in the SRLI process, and assessments were carried out by the IUCN Dragonfly Specialist Group, coordinated by Dr Viola Clausnitzer (Clausnitzer et al. (2009) Biological Conservation 142: 1864-1869) .
Odonata are widespread on all continents except Antarctica and are important as an indicator of habitat health. The larvae are a good indicator of water quality and aquatic habitat structure, while adult habitat selection is strongly dependant on vegetation structure. Some species disperse poorly, and so also indicate levels of habitat connectivity, while others thrive in recently disturbed habitats.
The Sampled Red List assessment of Odonata was completed in 2009 and estimated that more than half of the species were assessed as Least Concern and 13% were classed as threatened . Threatened species are mostly clustered in the Indonesian archipelago where large scale logging is prevalent, and in Australia where climate change effects are seriously impacting on freshwater systems. Other threats include water pollution, sedimentation and erosion.