The final instar larva of Heliaeschna idae Brauer is described and figured for the first time based on the exuvia from an advanced female larva collected in Sarawak, Borneo (East Malaysia). It is compared with the known larvae of the genus and is concluded to be most closely allied to Heliaeschna simplicia Karsch, with which it shares a unique structure on the anterior margin of the prementum of the labium, along with several other distinctive characters. The dorsal structure of the head of H. uninervulata is re-examined and illustrated. It is shown to bear a prominent convexity and tuft of long setae on the vertex which is similar to a structure previously recorded only in H. simplicia, and which is only weakly developed in H. idae. The taxonomic implications of these partly conflicting observations are discussed and it is concluded the Oriental members of the genus Heliaeschna might be separated into two or three separate genera, which are as yet unnamed.