A new species of Flacourtiaceae, Homalium palawanense, from Palawan, Philippines is described and illustrated.

The internal transcribed spacer (ITS) region of the nuclear ribosomalDNA was sequenced from 21 accessions of Viguiera from South America,including 14 from Brazil. Overall there was only a small amount of sequencevariation, less than 3.4% among South American samples and less than4.5% between the South American samples and the Mexican V. flava. Phylogenetic analysis revealed little divergence among the Braziliansamples of Viguiera. The low level of ITS sequence variation wasin striking contrast to the taxonomic diversity and chemical variability thathave been reported for Viguiera in Brazil. The low level of sequencevariation suggests that, despite its clear morphological and phytochemicaladaptations to the cerrado, Viguiera is probably a relatively recentaddition (less than 3 million years) to the flora of this area.

Rhododendron loranthiflorum was previously regarded as anarchipelagic endemic, with known stations in the Solomon Islands and New Britain.An exploratory survey of the Lakekamu Basin has now established the plant'spresence on the southern side of the New Guinea mainland. The Lakekamu provenancerepresents a geographical disjunction distinguishable as a separate subspecies,and is formally described as subsp. lakekamuensis.

Salsola cyrenaica subsp. antalyensis (Chenopodiaceae) from the S Anatolian coast near Finike is illustrated and describedas a new subspecies. Its anatomy, relationships, ecology and phytogeographyare discussed. The new subspecies differs from subsp. cyrenaica bythe reduced number of flowers per leaf axil, very dense axillary hairs, thesmaller size of most floral organs, mostly 3 instead of 2 stigmas and 5 not3 wings on the fruit. The new taxon grows in a narrow coastal strip of c.2kmonly, in open dwarf-shrub communities on limestone rocks from sea level toc.40m. It is the first representative of the S. longifolia group,sect. Coccosalsola, from Turkey and from the northern shores of theMediterranean.

Pinus halepensis and P. brutia hybridize extensively.The analysis of monoterpenoid and morphological variability of 122 pine treesat five sites showed that the within-site heterogeneity is high while theentire provenance diversity is comparable with that of a circum-Mediterraneanscale. Four morphotypes and four chemotypes were recognized. The congruencebetween morphological and monoterpenoid classification of pines was high (coefficientof contingency 89%) while thirteen family groups of genetically closelyrelated trees were found by means of a specifically designed sampling schemeof continuous classification – identification and re-sampling. Putativehybrids contributed substantially to the observed diversity and there is considerableheterogeneity between sites. Low-altitude sites, presumably susceptible tosea-level fluctuations, alluvial deposition and human influence, are in generalmore diverse at both levels of genetic complexity than inland sites. The hybridphenotypes were not merely intermediate forms of parental taxa, and in a multivariatesense they are located on a parabola in the space of morphological properties.The arrangement of hybrids in the monoterpenoid space did not reveal any clear-cutpattern except that three major composite axes can summarize 98.9%of the entire monoterpenoid variation. The observed pattern of variation wasinterpreted as a result of waves of introgressive influence of eastern P. brutia population on P. halepensis, which was caused by marinetransgressions in Pliocene and eustatic sea-level fluctuations in Pleistocene.The human influence on this introgression accelerated the process, and amplifiedthe resulted pattern, although it blurred in many instances the biogeographicroutes of germplasm mixing. Its bearing on the evolution of pines is discussed,and it was found that the ‘Eocene refugia hypothesis’ of C.I.Millar holds by analogy also in central Aegean pines.

Internal transcribed spacer (ITS) nrDNA sequences of 42 accessions(representing 28 species) of Aframomum revealed an unusually lowlevel of sequence variation, suggesting a recent radiation of the genus inAfrica. The sample of species analysed includes all the main morphologicalvariation and is based on wide geographical sampling. The Aframomumsequences varied from 187bp to 190bp (ITS 1) and 215bp to 216bp (ITS 2). Pair-wisesequence difference between accessions varied from 0% (e.g. A.luteoalbum and A. thonneri) to 2.74% (e.g. A. sp.nov. B to A. pseudostipulare). This contrasts with a comparabledata set for the SE Asian genus Alpinia in the same tribe (Alpineae) in which maximum pair-wise difference is six times greater (range 0.5–15.6%).A parsimony analysis of the in-group and out-group taxa supports the monophylyof the genus Aframomum, but does not resolve the relationships betweenthe in-group species. Four putative multi-species groups, however, have somejackknife support. The species sampled vary greatly in vegetative, floraland fruit characters. This morphological variation is not reflected in theITS sequence data. This may be a result of rapid radiation under conditionsof Pleistocene climatic change and effective dispersal of seeds by primates.

The following new species, subspecies and combinations are proposedfor plants occurring in the Flora of Bhutan area: Anaphalis cooperi Grierson & Springate, Artemisia bhutanica Grierson &Springate, Ixeridium beauverdianum (H.Lév.) Springate, Ligularia lancifera (J.R.Drumm.) Grierson, L. latiligulata (R.D.Good)Springate, Parasenecio chenopodifolius (DC.) Grierson, Saussureadonkiah C.B.Clarke ex Springate, S. pinnatiphylla Grierson &Springate, Tanacetum tatsienense var. tanacetopsis (W.W.Sm.)Grierson and Youngia silhetensis subsp. bhutanica Grierson &Springate. A description of Ligularia latiligulata is provided. Alectotype is designated for Saussurea obscura Lipsch.

Seven new species and one new subspecies in Scrophulariaceaefrom the Flora of Bhutan area are described. They include two newspecies of Euphrasia, E. chumbica R.R. Mill sp. nov. (Chumbi, Sikkim and C Bhutan) and E. melanosticta R.R. Mill sp. nov. (Sikkim, N Bhutan); one new species of Kickxia, K. papillosa R.R. Mill sp. nov. (E Bhutan); one new speciesof Lagotis, L. chumbica R.R. Mill sp. nov. (Chumbi);one new species of Neopicrorhiza, N. minima R.R. Mill sp. nov. (N Bhutan); two new species of Scrophularia, S.cooperi R.R. Mill sp. nov. (C Bhutan) and S. subsessilis R.R. Mill sp. nov. (N Bhutan); and a new subspecies of Ellisiophyllum pinnatum (Wall.) Makino, subsp. bhutanense R.R.Mill subsp. nov. (Bhutan). Alectra avensis (Benth.) Merr., Bacopa monnieri (L.) Pennell, Scrophularia himalayensis Royle, Striga asiatica (L.) Kuntze and S. densiflora Benth. are allrecorded from Bhutan and/or Sikkim for the first time. A brief argument isgiven for the continued use of hyphenated fel-terrae as the correctspelling of that epithet in Picria.

This study treats some structural aspects of a population of Callisthene fasciculata (Spr.) Mart. growing on a ridge in the Pantanalof Poconé, in Mato Grosso State, Brazil. The project was carried outin 1ha of cerradão (savanna forest) at Fazenda Retiro Campo Largo,Poconé. Callisthene fasciculata is a common species in thecerradão. Formations of C. fasciculata, regionally denominated`carvoeiro' and/or `carvoal', occur frequently. This species is of economicimportance because of its use for fence posts, charcoal and firewood. Dataon its population structure were analysed and are presented based on the circumferenceclass categories at breast height (cbh) and variation in height. The 869 individualtrees in the sample hectare included 17 families and 33 species, and weredominated by the 229 individuals of C. fasciculata.

The Pleistocenic Arc, which must have originated from the climaticshifts in South America during the late Pleistocene, ranges from the Caatingasof north-eastern Brazil through south-eastern Brazil to the Paraguay and Paranárivers confluence, into south-western Bolivia and north-western Argentina,and extends sporadically into dry Andean valleys of Peru or coastal westernEcuador. It is regarded as a new phytogeographic unit for South America, herenamed the Tropical Seasonal Forests Region, as it is characterized by a considerablenumber of endemic plant taxa at both generic and species level. The paradigmof the arc is the distribution pattern of Anadenanthera colubrina(Fabaceae), which, when superimposed on those of other woody speciesof seasonal forests, permits a reasonably accurate mapping of the new region,which might also have biogeographic implications for endemic bird taxa. Theplant communities of this newly recognized unit are unique in their natureand floristic composition, when compared with other floristic areas of thecontinent by means of classic phytosociological and numerical analyses (PCA).These ecosystems have remained submerged within other vegetation units inSouth American phytogeography (such as the Chaquenian or Amazonian regions),and have been particularly neglected in conservation policies. An urgent callis made for these areas to be preserved before they disappear, because theyare located in areas with some of the best agricultural soils of tropicalSouth America, and therefore subject to clearing for farming.