A revision of Lachnodius Maskell (Hemiptera, Coccomorpha, Eriococcidae)

Lachnodius Maskell is a genus of three named species that are part of an Australian radiation of felt scale insects that induce galls on Eucalyptus and Corymbia (Myrtaceae). A female's gall usually consists of an open-top pit in swollen plant tissue. Depending on the species, galls can occur on a host's leaves, buds, stems, or trunk. Here, we redescribe the named species: L.eucalypti (Maskell), L.hirsutus (Froggatt) and L.lectularius (Maskell), and describe seven new species: L.brimblecombei Beardsley, Gullan & Hardy, sp. n., L.froggatti Beardsley, Gullan & Hardy, sp. n., L.maculosus Beardsley, Gullan & Hardy, sp. n., L.melliodorae Beardsley, Gullan & Hardy, sp. n., L.newi Beardsley, Gullan & Hardy, sp. n., L.parathrix Beardsley, Gullan & Hardy, sp. n., L.sealakeensis Gullan & Hardy, sp. n. Descriptions are based primarily on adult females, but for some species short diagnoses of nymphal stages also are provided. The taxonomic history of Lachnodius is reviewed, with notes on their biology and ecology. A key to species based on the morphology of adult females is provided, and lectotypes are designated for Dactylopiuseucalypti Maskell and Lachnodiuslectularius Maskell.