Description of the final instar larva of Cephalaeschna risi Asahina, 1981 with notes on its semi-terrestrial lifestyle (Odonata: Aeshnidae)

Abstract

The final instar larva of Cephalaeschna risi Asahina, 1981 is described for the first time based on material from Taiwan. In Taiwan, the larva of C. risi can be separated from other aeshnid larvae by its relatively short antennae and presence of small protuberances on the legs. Diagnostic characters to distinguish it from other known larvae of Cephalaeschna are also discussed. A comprehensive description, detailed illustrations, bionomics and observations of the semi-terrestrial lifestyle of C. risi are presented. Finally, a key to the genera of Aeshnidae in Taiwan is proposed.