New species of alderfly genus S ialis ( M egaloptera: S ialidae) from C hina and V ietnam, with a key to species of S ialis from A sia

The alderfly genus S ialis is the most species‐rich group of the family S ialidae. However, discovery of new S ialis species is becoming difficult because of previous good faunal exploration. In this paper, we describe two new S ialis species from the southern part of E ast A sia, S . australis and S . jiyuni , based on materials from historical and recent collections. These two species are closely related to the insular species S . kumejimae and are among the early diverged species within S ialis . Presently, 32 species of S ialis are recorded from A sia. A key to all the S ialis species from A sia is provided.