Plesioneuron crassum subsp. chromeanum Takeuchi (Thelypteridaceae) is described as a new subspecies from one of Papuasia's most isolated karst districts. The subspecies is distinguished by bifacially glabrous pinnae with revolute lobes, conspicuously raised aerophores, and glandular-setiferous sporangia. Distributional records for Helicia acutifolia (Proteaceae) and Loranthus odoratus (Loranthaceae) are also reported with the new fern.

Within Rhytidocaulon macrolobum Lavranos, which is a widespread stapeliad in Saudi Arabia and in the Yemen, the subspecies minimum Meve & Collenette is described as new. This taxon is restricted to SW Saudia Arabia; it can be easily recognized by its miniature flowers, which are conspicuously smaller than the diameter of the stems, and by its bright-coloured corona.

A new species, Rhinacanthus flavovirens Amarasinghe & Wijesundara (Acanthaceae), from Sri Lanka, is described and illustrated. It is compared with the closely allied Rhinacanthus nasutus and R. polonnaruwensis. A key to Rhinacanthus species in Sri Lanka is also presented.

Six new species of the Neotropical genus Tetrapterys (Malpighiaceae) are described and illustrated: T. amazonica C.E.Anderson (Brazil, Colombia and Peru), T. andersonii C.E.Anderson (Mexico), T. callejasii W.R.Anderson (Colombia), T. molinae W.R.Anderson (Honduras), T. rzedowskii W.R.Anderson (Mexico) and T. steyermarkii W.R.Anderson (Colombia and Venezuela). All have 4(–6)-flowered umbels as the ultimate inflorescence units, glabrous yellow petals, and samaras with a small dorsal wing in addition to the four large lateral wings.

A new species of Gesneriaceae, Ornithoboea emarginata D.J.Middleton & N.S.Ly, is described from Vietnam. A proposed IUCN conservation assessment is provided.

A detailed description of Nepenthes reindwardtiana Miquel is provided, and its distribution is reviewed. One new variety, N. reindwardtiana var. samarindaiensis Adam & Wilcock, from Kalimantan in Borneo is described.

Thesmophora scopulosa Rourke (Stilbaceae) a monotypic genus endemic to the Ceres mountains, South Western Cape Province, South Africa, is described. It is characterized particularly by its pendulous ovules and 4-lobed corolla.

A taxonomic revision of Begonia veitchii Hook.f. is presented. Two taxa are newly recognised as synonyms of Begonia veitchii: B. baumannii Lemoine and B. clarkei Hook.f. Addditionally, two infraspecific taxa are newly described and illustrated: Begonia veitchii var. machupicchuensis Tebbitt, which is endemic to the Cusco Department of Peru, and B. veitchii var. lanatifolia Tebbitt, which is endemic to Chuquisaca Department, Bolivia. Begonia veitchii, as well as four taxa recognised as synonyms of B. veitchii – B. baumannii, B. rosaeflora Hook.f., B. coriacea A.DC. and B. clarkei – are lectotypified. A key, descriptions, distribution map and illustrations are provided for all the recognised infraspecific taxa of Begonia veitchii.

Populations of a rare species of Lalhyrus (Vicieae, Leguminosae), Lathyrus hirticarpus Mattatia & Heyn were located in Tartous province, Western Syria. A description and discussion of the relationship between this and allied species from Lathyrus L. sect. Lathyrus are provided.

Plant conservation genetics has been hampered by a lack of markers for studies of levels and patterns of variation in rare species. We investigated the levels of variation in several rare and widespread species of the western North American genus Lomatium Raf. (Apiaceae) using two relatively new molecular markers: AFLPs and single-strand conformation polymorphisms (SSCPs). For each species, approximately 150 AFLP loci have been scored, yielding estimates of species-level percent polymorphic loci in rare species ranging from near zero to over 80%. Levels of AFLP diversity were similar in two of the rare species, L. bradshawii (Rose ex Mathias) Mathas & Constance and L. ochocense Helliwell & Constance, and the widespread species. The third rare species, L. cookii Kagan, which has small populations, has low levels of diversity based on AFLPs. We also examined nucleotide diversity at the single-copy nuclear-DNA locus glyceraldehyde 3-phosphate dehydrogenase (Gap-C). PCR-amplified segments were analysed for allelic variation using SSCPs, and intrapopulational nucleotide polymorphisms were identified in both L. bradshawii and L. cookii. In the 211bp segment of Gap-C analysed, five nucleotide sites were segregating within populations of L. bradshawii and two in L. cookii.

Distribution maps and IUCN threat categories for the 30 named species of Hieracium section Alpina (Asteraceae) in Britain are given, based on taxonomic and distribution studies by D.J. Tennant and others over the last 30 years. Twenty-seven taxa are endemic to Scotland, one to England, one to Britain and one also occurs in mainland Europe and the Arctic. There are three main centres of diversity in Scotland: the Eastern Highlands (especially the Cairngorm Mountains), the Western Highlands and the Northern Highlands. Under the IUCN threat categories, seven taxa are Critically Endangered, seven are Endangered, two are Vulnerable, ten are Near Threatened and seven are Nationally Scarce. The main threats are collecting, natural events such as rock falls and avalanches, global warming, acid rain, over-grazing and tourism. There is particular concern for the long-term survival of four taxa.

Dracaena fragrans (L.) Ker Gawler is revised, similar species are critically compared and several of them, notably D. deremensis Engl. and D. deisteliana Engl. are reduced into synonymy. A formal classification with standard specimens for cultivated material currently in commerce is proposed.

Twenty-two species of Alpinia hitherto placed in sections Psychanthus and Pleuranthodium are transferred to the genus Psychanthus Ridley. The justification for the acceptance of Psychanthus, which is based on the cup-shaped character of the labellum is discussed, and the necessary new combinations made.

A key is given to distinguish Jamesbrittenia, Camptoloma and Lyperia from Sutera, a genus with which they have hitherto usually been equated. Twenty one species and one subspecies of Jamesbrittenia are newly described, and 63 new combinations are made (two at varietal level).

Pterospermum mengii P.Wilkie (Dombeyoideae, Malvaceae/Sterculiaceae) from Cambodia and Vietnam is described as new to science and illustrated. It is most similar to Pterospermum pecteniforme Kosterm., sharing a distinctive wavy ridge at the margin of each locule of the capsular fruit, but differing by its larger leaves, oblong to obovate leaf shape, deeply cordate leaf base, and stellate indumentum on the undersurface of the leaves and fruit.