D.A.L. DAVIES & P. TOBIN (1984, The dragonflies of the world, a systematic list of the extant species of Odonata, Vol. 1: Zygoptera, Anisozygoptera, Soc. Int. Odonatol., Utrecht) introduced the new family, Diphlebiidae, to house a single genus Diphlebia Selys, 1896. Presently in some publications, e.g. in G. BECHLY (1996, Petalura Special-Volume 2), G. THEISCH1NGER & J. HAWKING (2006, The complete field guide to dragonflies of Australia, Collingwood) and in World Odonala list by SCHORR et al., available on internet at http://www.ups. edu/x6140.xml, two genera Diphlebia and Philoganga Kirby, 1890 are included in the family called Diphlebiidae. R. NOVELO-GUTIERREZ (1995, Odonulologica 24: 73-87) included also Lestoidea Tillyard, 1913 in this family (but in a separate subfamily Lestoideinae). As already pointed out by J. VAN TOL (1995, Odonatologica 24: 245-248) there exist available family-group names introduced on all three genera Diphlebia, Philoganga and Lestoidea, viz. (in chronological order) Lestoidinae [sic!] by MUNZ (1919, Mem. am. ent. Soc. 3: 1-78), Philoganginae (by C.H. KENNEDY, 1920, Ohio J. Sci. 21: 19-29) and Diphlebiidae (DAVIES & TOBIN, 1984, see above). Based on the principles of nomenclature, Van Tol concluded as follows ’’The correct family-group name for a group made of Diphlebia, Philoganga and Lestoidea is thus based on Lestoidea, introduced by MUNZ (1919): Lestoideidae. Novelo-Gutierrez also distinguishes two subfamilies, one including Diphlebia and Philoganga, the other Lestoidea only. Their correct names are Philoganginae and Lestoideinae respectively.” Consequently, if the two genera Diphlebia and Philoganga alone are ranked as a family, its correct name is Philogangidae Kennedy, 1920.