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Tribe Macadamieae (91 spp., 16 genera; Proteaceae) is widespread across the southern hemisphere on all major fragments of Gondwana except New Zealand and India. Macadamia is cultivated outside its natural range as a 'nut' crop (notably in Hawaii, where it is the principal orchard crop). We sampled seven DNA regions and 53 morphological characters from the tribe to infer its phylogeny and address the common assumption that the distribution of the extant diversity of the tribe arose by the rafting of ancestors on Gondwanan fragments. Macadamia proves to be paraphyletic with respect to the African genus Brabejum, the South American genus Panopsis, and the Australian species Orites megacarpus. We erect two new generic names, Nothorites and Lasjia, to produce monophyly at that rank. The earliest disjunctions in the tribe are inferred to be the result of long-distance dispersal out of Australia (with one possible exception), rather than vicariance. Evolution of tardy fruit dehiscence is correlated with these dispersals, and the onset of the Antarctic Circumpolar Current (ACC) precedes them. We suggest that the ancestors of extant diversity arrived on their respective continents via the ACC, and we recognize that this is a mechanism precluded, rather than facilitated, by Gondwana's terrestrial continuity. Key words: biogeography; fruit evolution; Gondwana; hydrochory; long-distance dispersal; Macadamia; relaxed-clock molecular dating; phylogenetics; Proteaceae; vicariance.

Sunken, covered, and encrypted stomata have been anecdotally linked with dry climates and reduced transpiration and therefore have been used to infer dry palaeoclimates from fossils. This study assesses the evolutionary and ecological associations of such stomatal protection in a model system--the diverse southern hemisphere family Proteaceae. Analyses were based on the morphology of over 1400 Australian, South African, New Caledonian, New Zealand, and South American species, anatomy of over 300 of these species, and bioclimatic data from all 1109 Australian species. Ancestral state reconstruction revealed that five or six evolutionary transitions explain over 98% of the dry climate species in the family, with a few other, minor invasions of dry climates. Deep encryption, i.e., stomata in deep pits, in grooves, enclosed by tightly revolute margins or strongly overarched by cuticle, evolved at least 11 times in very dry environments. Other forms of stomatal protection (sunken but not closely encrypted stomata, papillae, and layers of hairs covering the stomata) also evolved repeatedly, but had no systematic association with dry climates. These data are evidence for a strong distinction in function, with deep encryption being an adaptation to aridity, whereas broad pits and covered stomata have more complex relations to climate. Key words: ancestral state reconstruction; bioclimatic modeling; palaeoclimate; papillae; phyloclimatic analysis; Proteaceae; sclerophylly; stomatal encryption; water relations; xeromorphy.

Species of the major Southern Hemisphere family, proteaceae, have many scleromorphic anatomical structures in their leaves. Many of these structures (very thick cuticles and five anatomically distinct structures beneath the epidermis) are associated with the leaf surface exposed to direct light. These structures increase the path through which solar radiation must pass before reaching the mesophyll. In this study, such structures are proposed to protect the mesophyll from excess solar radiation, including photosynthetically active, ultraviolet, and possibly infrared radiation. Scleromorphic structures of the upper leaf surface and nonscleromorphic photoprotective structures (dense trichomes and papillae of the upper surface) occur almost exclusively in open vegetation. Open vegetation species of proteaceae occur in oligotrophic and/or cold and/or dry places, where protection from light in excess of photosynthetic capacity and damage from ultraviolet light should be most important. Data from 123 species and a supertree constructed from available molecular phylogenies are used to show that the proposed photoprotective structures evolved many times within proteaceae. In tests of correlated evolution, the proposed photoprotective structures are significantly associated with open vegetation, but not with dry habitats. Key words: anatomy; cuticle; photoprotection; proteaceae; scleromorphy; sclerophylly; ultraviolet; xeromorphy.

DNA sequence data from plastid matK and trnL-F regions were used in phylogenetic analyses of Diurideae, which indicate that Diurideae are not monophyletic as currently delimited. However, if Chloraeinae and Pterostylidinae are excluded from Diurideae, the remaining subtribes form a well-supported, monophyletic group that is sister to a 'spiranthid' clade. Chloraea, Gavilea, and Megastylis pro parte (Chloraeinae) are all placed among the spiranthid orchids and form a grade with Pterostylis leading to a monophyletic Cranichideae. Codonorchis, previously included among Chloraeinae, is sister to Orchideae. Within the more narrowly delimited Diurideae two major lineages are apparent. One includes Diuridinae, Cryptostylidinae, Thelymitrinae, and an expanded Drakaeinae; the other includes Caladeniinae s.s., Prasophyllinae, and Acianthinae. The achlorophyllous subtribe Rhizanthellinae is a member of Diurideae, but its placement is otherwise uncertain. The sequence-based trees indicate that some morphological characters used in previous classifications, such as subterranean storage organs, anther position, growth habit, fungal symbionts, and pollination syndromes have more complex evolutionary histories than previously hypothesized. Treatments based upon these characters have produced conflicting classifications, and molecular data offer a tool for reevaluating these phylogenetic hypotheses. Key words: Acianthinae; Chloraeinae; Codonorchis; Diurideae; DNA sequences; matK; Megastylis; molecular systematics; monocots; Orchidaceae; phylogenetic relationships; trnL-F.