Bornean Lymantriidae (297 species in 40 genera and 5 tribes) are described. For each species, a diagnosis and the geographical range are given and, where known, details of habitat preference and biology. Summary lists are provided of the new taxa described (3 tribes, 4 genera, 74 species and 1 subspecies) as well as of numerous other taxonomic changes. A checklist of all species summarises the fauna.
The family is defined and described, with comments on its position within the Noctuoidea and higher classification within it, and aspects of its biogeography and ecology are noted.
Attempts are made to resolve the generic status of taxa previously placed in Dasychira Hübner and Euproctis Hübner, and to circumvent the obstacle to progress in the genus Redoa Walker (= Arctornis Germar) presented by the unavailability of Toxopeus type material.
The family placement of the genus Allotoma Roepke is considered; it is probably bombycoid rather than noctuoid, but does not fall readily into any bombycoid family.