A morphological study of herbarium and field-collected specimens, using phenetic techniques of agglomerative classification, ordination and minimum spanning trees, and covering the geographic range of the Holly Grevillea, G. ilicifolia (R.Br.) R.Br. sensu lato, has resulted in the recognition of three species and four subspecies. The taxa are based on leaf form, noted by previous authors to be highly variable between populations.

Abstract. The holly grevilleas are an informal grouping of 15 species (19 taxa) of woody shrubs from south-eastern Australia, with a centre of distribution in central to western Victoria. Many of the species are narrowly endemic. The present study is the first molecular-phylogenetic analysis of the group, with the aim of providing an evolutionary framework for assessing species-level taxonomy and conservation priorities. Analyses using the nrDNA internal transcribed spacer (ITS) regions were complicated by the presence of divergent paralogues, including inferred pseudogenes; analyses restricted to presumed orthologous, functional ITS sequences were uninformative. Combined analyses of three chloroplast intergenic spacers (trnQ-5 0 rps16, trnL-trnF and rpoB-trnC) strongly support the monophyly of a core group of 16 taxa (the 'southern holly grevilleas') from Victoria and South Australia. However, nodes outside this group are poorly resolved and poorly supported, and the relationships of taxa from New South Wales and eastern Victoria (the 'northern holly grevilleas') are unclear. Among the southern holly grevilleas, the following four distinct and partly sympatric cpDNA clades are identified: the 'Grevillea ilicifolia', 'G. aquifolium', 'G. dryophylla' and 'G. repens' clades, among which the earliest and most strongly supported divergence is that of the western-most 'G. ilicifolia' clade. Variation in cpDNA is incongruent with current species-level taxonomy, especially for G. aquifolium (polyphyletic), G. montis-cole (polyphyletic, but the two subspecies each monophyletic) and G. microstegia (nested in G. aquifolium). The effects of incomplete chloroplast lineage sorting, gene flow through hybridisation or introgression, and inappropriate taxonomy are possible explanations for this incongruence. The formal conservation listing for some species within the holly grevillea group requires re-evaluation.

Trichomes of Tremandra R.Br. ex DC., Platytheca Steetz and Tetratheca Sm. (Elaeocarpaceae, former Tremandraceae), together with two outgroup species of Elaeocarpus L., are illustrated using Scanning Electron Microscopy, and their distribution on various plant organs is documented. Various trichomes types were identified that relate taxa: simple hairs, stellate hairs, short glandular trichomes, long glandular trichomes, and three forms of tubercules. Both outgroup and ingroup taxa have simple hairs. Stellate hairs are confirmed as unique to Tremandra. Prominent and sculptured multi-celled tubercules, some bearing a stout hair, are characteristic of Platytheca. Smaller multicelled tubercules occur in both Platytheca and Tetratheca, except for the Western Australian taxon Te. filiformis (possibly plesiomorphic). Unicellular tubercules (papilla) characterise two species of Tetratheca. Short glandular trichomes, usually found on the ovary, also occur in both of these genera but not in all species (possibly secondary losses), while long glandular trichomes, usually on stems and leaves, occur only in some groups of Tetratheca. Within Tetratheca, Western Australian taxa that have five-merous flowers fall into three 'groups': seven species (together with one from South Australia) that have short glandular trichomes but no long glandular trichomes; six species that have long glandular trichomes but no short glandular trichomes; and four species that have both trichome types. All other species of Tetratheca have four-merous flowers and form two 'groups': twelve eastern species (including one from South Australia) that have both short glandular trichomes and long glandular trichomes; four western species and six eastern species that lack short glandular trichomes. Based on these characters, a phylogenetic hypothesis for the three genera is presented.