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Aim: Palms are an iconic, diverse and often abundant component of tropical ecosystems that provide many ecosystem services. Being monocots, tree palms are evolutionarily, morphologically and physiologically distinct from other trees, and these differences have important consequences for ecosystem services (e.g., carbon sequestration and storage) and in terms of responses to climate change. We quantified global patterns of tree palm relative abundance to help improve understanding of tropical forests and reduce uncertainty about these ecosystems under climate change. Location: Tropical and subtropical moist forests. Time period: Current. Major taxa studied: Palms (Arecaceae). Methods: We assembled a pantropical dataset of 2,548 forest plots (covering 1,191 ha) and quantified tree palm (i.e., ≥10 cm diameter at breast height) abundance relative to co-occurring non-palm trees. We compared the relative abundance of tree palms across biogeographical realms and tested for associations with palaeoclimate stability, current climate, edaphic conditions and metrics of forest structure. Results: On average, the relative abundance of tree palms was more than five times larger between Neotropical locations and other biogeographical realms. Tree palms were absent in most locations outside the Neotropics but present in >80% of Neotropical locations. The relative abundance of tree palms was more strongly associated with local conditions (e.g., higher mean annual precipitation, lower soil fertility, shallower water table and lower plot mean wood density) than metrics of long-term climate stability. Life-form diversity also influenced the patterns; palm assemblages outside the Neotropics comprise many non-tree (e.g., climbing) palms. Finally, we show that tree palms can influence estimates of above-ground biomass, but the magnitude and direction of the effect require additional work. Conclusions: Tree palms are not only quintessentially tropical, but they are also overwhelmingly Neot

ForestGEO is a network of scientists and long-term forest dynamics plots (FDPs) spanning the Earth's major forest types. ForestGEO's mission is to advance understanding of the diversity and dynamics of forests and to strengthen global capacity for forest science research. ForestGEO is unique among forest plot networks in its large-scale plot dimensions, censusing of all stems ≥1 cm in diameter, inclusion of tropical, temperate and boreal forests, and investigation of additional biotic (e.g., arthropods) and abiotic (e.g., soils) drivers, which together provide a holistic view of forest functioning. The 71 FDPs in 27 countries include approximately 7.33 million living trees and about 12,000 species, representing 20% of the world's known tree diversity. With >1300 published papers, ForestGEO researchers have made significant contributions in two fundamental areas: species coexistence and diversity, and ecosystem functioning. Specifically, defining the major biotic and abiotic controls on the distribution and coexistence of species and functional types and on variation in species' demography has led to improved understanding of how the multiple dimensions of forest diversity are structured across space and time and how this diversity relates to the processes controlling the role of forests in the Earth system. Nevertheless, knowledge gaps remain that impede our ability to predict how forest diversity and function will respond to climate change and other stressors. Meeting these global research challenges requires major advances in standardizing taxonomy of tropical species, resolving the main drivers of forest dynamics, and integrating plot-based ground and remote sensing observations to scale up estimates of forest diversity and function, coupled with improved predictive models. However, they cannot be met without greater financial commitment to sustain the long-term research of ForestGEO and other forest plot networks, greatly expanded scientific capa

Based on morphological and molecular data, we have concluded that Acmena, Acmenosperma, Cleistocalyx, Piliocalyx and Waterhousea should be combined with Syzygium. The five genera are formally transferred to Syzygium and new names provided for those of their accepted representatives for which names are as yet not available in Syzygium, with the exception of the New Caledonian members of Piliocalyx as these currently are being revised.

Priorities of workers within the tropics are likely to substantially differ from those outside. Within much of the tropics, including Indonesia, Malaysia, and Papua New Guinea many biologists do not view logging, which is generally the primary cause of modification of residual primary forest, as a likely cause of extinction except when followed by immigration and cultivation as it so often is in the Philippines and Indochina (and also some parts of Indonesia). These workers therefore anticipate increasingly intensive and diversified use of the forest flora as the area of natural vegetation declines. They want better access to appropriate knowledge to this flora for users, in the form of manuals in simple language with good keys based on field characters, and with field descriptions and information about ecology as well as distribution, and known potential or actual useful attributes. This requires collection of extensive field knowledge beyond museum specimens.

Small or large resinous usually evergreen trees, usually buttressed, and often (if large trees) with flaky or fissured bark. Some or most parts with a tomentum of fascicled hairs, or sometimes single hairs, unicellular or multicellular glandular hairs, or multicellular, short or long lobed or peltate hairs. Leaves alternate, simple, margin entire or sinuate, not crenate, terminating ± abruptly at the ± prominent geniculate petiole, penninerved (in Dryobalanops and some Hopea nerves ~, dense and slender), often with domatia in axils between nerves and midrib or along midrib and (rarely) nerves; tertiary nerves scalariform or reticulate. Stipules paired, large or small, persistent or fugaceous, leaving small to amplexicaul scars. Inflorescence paniculate, racemose, rarely cymose, ± regularly, rarely irregularly, branched, terminal or axillary; bracts and bracteoles paired, small or large, persistent or fugaceous. Flowers secund or distichous, bisexual, actinomorphic, scented, nodding. Calyx persistent, 5-merous; 2-5 sepals usually greatly enlarging into wing-like lobes in fruit; sepals either free to base, imbricate in bud, remaining so or becoming valvate in fruit, or fused at base, forming a cup or tube ± enclosing the fruit, adnate to or free from it. Corolla 5-merous, contorted, base connate or free, usually partially or entirely unicellular hairy. Stamens 5-110, 1-3 verticillate or irregular, hypogynous or subperigynous, centrifugal; filaments compressed or filiform, free or connate, frequently cohering with petals on falling; anthers erect, 2-celled with (2-)4 pollen sacs, introrse or laterally dehiscent; tapetal cells binucleate, pollen grains 2-celled at anthesis; connective with short or prominent appendage. Ovary superior or semi-inferior, 3-, rarely 2-, locular; style ± thickened at base into a stylopodium, entire or trifid towards apex; stigma obscure or prominent, 3- or 6-lobed. Ovules 2(-3) in each loculus, axile, pendulous or laterally anatropous, biteg

Taxonomists working with material collected by the Sarawak Forest Department have often been hard put to decide how to quote numbers. Is the departmental series number preceeded by a letter S, or an F, or would it be best to quote only the collector and the number? I have tried to unravel the history of the Sarawak Forest Department herbarium number series in order to provide a guide to unequivocal citation. This has not been easy, as all collecting books previous to 1951 have disappeared, apparently during the second world war; many of the herbarium collections are now missing at Kuching and Kepong, where most were distributed, for the same reasons, though there seem also to have been large gaps in the series where numbers were never used. What has eventually been brought to light has been a masterpiece of confusion only vied with in complexity by its Sarawakian forbear, the remarkable numbering, or rather lettering, system of Haviland (explained in Kew Bull. 1907, 197— 198).

The taxonomy of the largely endemic dipterocarp flora of Ceylon is brought into line with that of the rest of the Asiatic subfamily, and a new species is described. Stemonoporus lewisianus Trimen ex Hook. f. finds its correct place at last in Cotylelobium. Balanocarpus brevipetiolaris (Thw.) Alston is transferred to Hopea. Shorea pallescens Ashton (sect., subsect., Shoreae) is described for the first time. Shorea stipularis Thw. is ascribed to sect. Anthoshorea Heim. Doona Thw. is reduced, as a separate section, to Shorea Roxb. ex Gaertn.f., necessitating 7 new combinations and 3 new names. Doona oblonga Thw. is united with Doona disticha (Thw.) Pierre under the name Shorea disticha (Thw.) Ashton. Doona nervosa Thw. is reduced to Doona cordifolia Thw., now named Shorea cordifolia Ashton. The description of the genus Stemonoporus is amplified; a key is provided to all species. Stemonoporus acuminatus (Thw.) Bedd. is further defined. Stemonoporus nervosus Thw. is reduced to Stemonoporus lancifolius (Thw.) Ashton. Shorea reticulata Thw. and Stemonoporus moonii Thw. (= Vateria moonii Thw.) are excluded from the family.