The genus Phellodendron (Rutaceae) is revised. This work is based on herbarium collections and field observations in eastern Asia. Two species are recognized: Phellodendron amurense Rupr. and Phellodendron chinense C.K.Schneid. All other specific and infraspecific names published in the genus are reduced to synonymy or excluded from the genus. Detailed morphology, character variability, an identification key, a distribution map, line drawings, and taxonomic treatments and lists of specimens examined are provided.

A new species from Sardinia occurring on the Gennargentu massif, Ruta lamarmorae (Rutaceae), is described and illustrated. Its relationships with R. corsica, a species widespread in the Corsican mountains, are examined.

Berlinia Sol. ex Hook.f. (Leguminosae – Caesalpinioideae) is under investigation with two main goals: (i) to delimit and describe the species, and (ii) to elucidate their relationships. Delimitation and description is now largely completed and is presented in this synopsis. The genus Berlinia is assessed as comprising 18 species. Keys to the species are presented and for each species a brief description, selected synonymy and specimen citations are given. A monograph of Berlinia including a full taxonomic treatment and the results of the phylogenetic investigation will be published later by the senior author.

Two new species of Ormosia (Leguminosae – Papilionoideae, Sophoreae) are described: Ormosia carinata N.Zamora and Ormosia intermedia N.Zamora.

Four new species of Begonia (Begoniaceae) are described from the Indonesian island of Sulawesi. All four species (Begonia chiasmogyna M.Hughes, Begonia macintyreana M.Hughes, Begonia mendumae M.Hughes and Begonia stevei M.Hughes) belong to Begonia section Petermannia, and they increase the number of Begonia species known from the island to 30.

Three new species of Chilocarpus (Apocynaceae – Rauvolfioideae) from Malesia are described: Chilocarpus hirtus D.J.Middleton, Chilocarpus pubescens D.J.Middleton and Chilocarpus sarawakensis D.J.Middleton. Preliminary conservation assessments are proposed.

Nineteen miscellaneous species of Bornean Cyrtandra are dealt with. Cyrtandra atrichoides, C. congestiflora, C. crockerella, C. dulitiana, C. kanae, C. libauensis, C. plicata, C. vaginata and C. disparoides subsp. inconspicua are newly described. Descriptions and discussion are provided for C. erythrotricha and C. poulsenii, originally published with diagnoses only. Cyrtandra axillaris, C. longicarpa and C. microcarpa are also described, while C. borneensis, C. dajakorum, C. glomeruliflora, C. latens and C. prolata are reduced to synonymy.

Until recently the genus Didymocarpus Wall. (Gesneriaceae) was used in an unwarrantably wide sense and included more than 180 species. It has now been remodelled and restricted to around 70 species. Of these, 18 species and one variety are known to occur in Thailand. To clarify the relationships among Thai species of Didymocarpus we sequenced the internal transcribed spacers (ITS) of nuclear ribosomal DNA (nrDNA) from a sample of 23 taxa, including 15 from Thailand, four from China, three from Malaysia and one from Bhutan. Seventeen morphological characters were coded for all 23 taxa and optimized onto a retention index (RI) reweighted maximum parsimony (MP) tree. The phylogenetic analyses suggested that Didymocarpus taxa formed a strongly supported monophyletic clade, with several supported subclades. The combination of molecular phylogeny and optimization of morphological characters suggests the presence of three distinct groups: the first, corresponding to Didymocarpus sect. Elati Ridl., includes plants with tall stems, yellow or white flowers and one-celled conoid or two-celled headed pigment glands; the other two groups, which represent Didymocarpus sect. Didymocarpus, both contain plants with dwarfed stems and violet or purple flowers, but are distinguished by the presence of both four-celled conoid or onecelled globose glands in one, and the absence in the other. Optimization of geographical locality onto the phylogeny led us to propose the hypothesis that, based on this sample, the geographical origin of Didymocarpus is the Malay Peninsula, and the ancestral corolla colour is white/yellow. Subsequent dispersal northward through southern and northern Thailand to China and Bhutan was accompanied by the evolution of a purple/violet corolla colour.

The new species Drypetes bakembei D.J.Harris & Wortley (Putranjivaceae), from tropical forest in the south west Central African Republic, is described and illustrated.

Recent studies on molecular phylogeny of complex thalloid liverworts (Marchantiopsida) have revealed the need to recognize four new higher taxa: Family Neohodgsoniaceae, Order Neohodgsoniales, Order Lunulariales and Family Dumortieraceae. These are formally described along with notes on their differences from other complex thalloid liverworts.

Caudella bipolaris sp. nov. (Microthyriaceae), found on leaves of the liana Bredemeyera floribunda Willd. (Polygalaceae) from the Brazilian cerrado, is described and illustrated. This is the fourth known Caudella species and the first reported on a member of the family Polygalaceae. Unique within the genus are the species' bipolar ascospore appendages.

Covering an area of 177,000 hectares, the region known within Belize as the Chiquibul Forest comprises the country's largest forest reserve and includes the Chiquibul Forest Reserve, the Chiquibul National Park and the Caracol Archaeological Reserve. Based on 7047 herbarium and live collections, a checklist of 1355 species of vascular plant is presented for this area, of which 87 species are believed to be new records for the country. Of the 41 species of plant known to be endemic to Belize, four have been recorded within the Chiquibul, and 12 species are listed in The World Conservation Union (IUCN) 2006 Red List of Threatened Species. Although the Chiquibul Forest has been relatively well collected, there are geographical biases in botanical sampling which have focused historically primarily on the limestone forests of the Chiquibul Forest Reserve. A brief review of the collecting history of the Chiquibul is provided, and recommendations are given on where future collecting efforts may best be focused. The Chiquibul Forest is shown to be a significant regional centre of plant diversity and an important component of the Mesoamerican Biological Corridor.

A study was made of the transition between the cerrado and Amazonian forest biomes on the Serra do Roncador in the northeast of Mato Grosso State, Brazil. The transition was sampled by recording the species and circumference at breast height (cbh) of all woody species ≥ 15 cm cbh on five 20 × 10 m plots in each of the following four communities: ecotonal vegetation (Cerradão areas 1 and 2), and forest (Forest areas 1 and 2); while in the Cerrado sensu stricto a more rapid method had to be used because of time constraints. A total of 138 species was recorded and the results were analysed using Sørensen and Morisita Indices, TWINSPAN and DCA. In addition, comparisons were made with data from studies undertaken in 1968 in the same area by the Xavantina-Cachimbo Expedition. No species was common to all communities sampled but a seral succession of important species occurs along the transition. The Sørensen and Morisita Indices demonstrate this, with the Cerrado s.s. and Forest 2 at the two extremes showing no species in common (zero similarity) and Cerradão 1 and 2 giving the very high figures of Sørensen 0.64 and Morisita 0.84. The ecotonal cerradão is a very characteristic Dystrophic facies cerradão with Hirtella glandulosa, Emmotum nitens, Sclerolobium paniculatum and Vochysia haenkeana as its typical indicator species. The ecotone studied in the present work represents the comparatively abrupt transition from cerrado to the peripheral form of Amazonian forest (dry forest, mata seca) on flat terrain with a uniform very dystrophic soil. Other workers have suggested that this type of transition may be restricted to the headwaters of the Xingu basin, but one of the present authors has seen similar vegetation at localities in Maranhão, Rondônia, and on the Mato Grosso–Rondônia border. Comparison of the present vegetation with the survey made in 1968 shows that in this area the advancing face of the Amazonian forest has extended about 7 km southwards into the cerrado. However, in the majority of places this process has been obscured by forest clearing for agriculture. The study draws attention to the urgent need for the establishment of conservation areas in this extremely threatened and very little studied ecotone.

The floristic composition of campo limpo úmido, a moist savanna grassland vegetation of the cerrado biome, is still little described, even though its herbs and subshrubs form a major component of the cerrado vegetation. The objective of this study was to characterize the floristic richness of the herbaceous and subshrub layer of a moist grassland at the Água Fria Farm, Alto Paraíso, Goiás State (14°04′8.83″S, 47°30′33.1″W). The principal use of such grasslands is to graze cattle; in addition, local people collect vast numbers of selected species of wild plants to sell for the decorative dried plant trade, or for their medicinal qualities. Little is known, however, about the sustainability of this extractivism. A survey of a 21 ha area, with intensive quarterly collections of herbarium specimens, was made from April 2000 to March 2001. Despite the small size of the study site it proved to be very rich floristically. A total of 207 species in 90 genera and 33 families was registered in the area. Thirty-one species not yet recorded in the checklist of the flora of the cerrado biome were found in this study, plus three that seem to be new to science. The richest families were Cyperaceae (30 species), Poaceae (28), Xyridaceae (23), Eriocaulaceae (20), Asteraceae (18), and Orchidaceae and Melastomataceae with 10 species each. These results suggest the need for more research on the moist grassland to provide overall estimates for the plant species richness of this widespread vegetation type and as a basis to help guide conservation and management policies.