Physospermopsis siamensis Esser & M.F.Watson is described as a new species from material collected in northern Thailand. This is the first record of Physospermopsis (Umbelliferae, Apiaceae) from Thailand, and represents a significant southern extension of the geographic range of this largely Sino-Himalayan genus. Comparison is provided with P. shaniana, its closest morphological ally, and the key to genera given in the Flora of Thailand account for Umbelliferae is revised.

The fruits of two anomalous African woody Apiaceae, Polemanniopsis marlothii and Steganotaenia araliacea, differ in structure when mature though the ovaries are very similar, both being heteromorphic in young flower stage. This unexpected heteromorphism in S. araliacea has important implications for future studies of basal genera and the interpretation of fruit characters in general. Both taxa also have unique ‘intrajugal cavities’ in the ovaries and fruits, which supports the idea that the two genera are closely related, sharing some characters with the Hydrocotyloideae and Saniculoideae. This provides morphological and anatomical evidence to support the previous hypotheses on their relationship with Saniculoideae. Their basal position is also supported by characters shared with other basal genera previously included in Hydrocotyloideae, such as the lateral wings and slightly lignified endocarp in Polemanniopsis and Steganotaenia.

Recent trends in compilation of world consensus family classifications from existing floristic and monographic data, and demands for alpha-taxonomic and other traditional phenetic data for analysis with phylogenetic reconstructions derived from DNA sequences are discussed. Obstacles hindering the production of a meaningful, comprehensive data set for Apiaceae include: (1) the lack of comparable non-molecular phenetic data; (2) incomplete coverage of family accounts in recent Floras, particularly in the southern hemisphere; (3) large, artificial genera awaiting monographic treatment; and (4) the lack of database systems that handle differences in taxonomic opinion (alternative classifications). The use of electronic communication, particularly the Internet, can help to accelerate progress in these areas through promoting collaboration and information exchange. The contribution of the Apiales Resource Centre website (especially the umbellifer areas: www.umbellifers.com) is highlighted.

Australian Apiaceae, dominated by Hydrocotyloideae Link, are characterized by a number of enigmatic genera, the phylogenetic relationships of which are obscure. A cladistic analysis using morphological and anatomical data indicated that Apiaceae are monophyletic and Hydrocotyloideae form a grade between a paraphyletic Araliaceae and a monophyletic Apioideae Drude+Saniculoideae Burnett. Beyond this, there was no support for past suprageneric arrangements within the order. Hydrocotyleae Spreng. and their constituent subtribes were polyphyletic, as were the subtribes of Mulineae DC. The relationships between Australian genera were not well resolved although the analysis did provide a good indication of broad generic affinities.

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.

Of the 455 known genera in Apiaceae (Umbelliferae), 41% are monotypic and 26% comprise only two or three species each. Similarly, of the 16 genera constituting Scandiceae Spreng. subtribe Scandicinae Tausch, seven (Balansaea Boiss. & Reut., Kozlovia Lipsky, Krasnovia Schischk., Myrrhis Mill., Myrrhoides Fabr., Sphallerocarpus DC. and Todaroa Parl.) are monotypic, and two (Neoconopodium Pimenov & Kljuykov and Tinguarra Parl.) are bitypic. Phylogenetic analysis of the subtribe, using molecular (rDNA ITS), morphological and anatomical data, indicates that the number of genera may be reduced with only three, Todaroa, Sphallerocarpus and Myrrhis, retained as monotypic. Remaining taxa form eight clades that are supported by high bootstrap values and are morphologically distinct. Four of these clades (Anthriscus Pers., Geocaryum Coss., Osmorhiza Raf. and Scandix L.) are equivalent to currently recognized genera. Kozlovia, Krasnovia and Neoconopodium form a well-supported clade that may be recognized as the single genus Kozlovia, and Myrrhoides is grouped with Chaerophyllum L. Tinguarra and Athamanta L. form a monophyletic group that is well supported by analyses of morphology, fruit anatomy, and combined morphological, anatomical and ITS sequence data; however, this group is not maintained in separate analyses of ITS sequences. Similarly, the group formed by Conopodium W. D. J. Koch and Balansaea is monophyletic in morphological, anatomical, and combined analyses, but is not supported by the separate analyses of ITS sequence data. All of these groups are well delimited on the basis of fruit characters that have long been regarded as essential in umbellifer taxonomy. One new combination is proposed: Athamanta montana (Webb ex H. Christ.) Spalik, A. Wojew. & S. R. Downie.

Phylogenetic analyses of chloroplast gene (rbcL, matK), intron (rpl16, rps16, rpoC1) and nuclear ribosomal DNA internal transcribed spacer (ITS) sequences and chloroplast DNA restriction sites, with supplementary data from variation in size of the chloroplast genome inverted repeat, have been used to elucidate major clades within Apiaceae (Umbelliferae) subfamily Apioideae Drude. This paper summarizes the results of previously published molecular cladistic analyses and presents a provisional classification of the subfamily based on taxonomic congruence among the data sets. Ten tribes (Aciphylleae M. F. Watson & S. R. Downie, Bupleureae Spreng., Careae Baill., Echinophoreae Benth., Heteromorpheae M. F. Watson & S. R. Downie, Oenantheae Dumort., Pleurospermeae M. F. Watson & S. R. Downie, Pyramidoptereae Boiss., Scandiceae Spreng. and Smyrnieae Spreng.) are erected or confirmed as monophyletic, with Scandiceae comprising subtribes Daucinae Dumort., Scandicinae Tausch and Torilidinae Dumort. Seven additional clades are also recognized but have yet to be treated formally, and at least 23 genera examined to date are of dubious tribal or clade placement. The utility of these different molecular markers for phylogenetic inference in Apioideae is compared based on maximum parsimony analyses of subsets of previously published molecular data sets. Of the six loci sequenced, the ITS region is seen to be evolving most rapidly and rbcL is the most conservative. Intermediate in rate of evolution are matK and the three chloroplast introns; with rpl16 and rps16 evolving slightly faster than matK or rpoC1. The analysis of restriction sites, however, provided 2–4 times more parsimony informative characters than any single DNA locus sequenced, with estimates of divergence just slightly lower than that of the ITS region. The trees obtained from separate analyses of these reduced data sets are consistent with regard to the major clades inferred and the relationships among them. Similar phylogenies are obtained by combining data or combining trees, representing the supermatrix and supertree approaches to phylogenetic analysis, respectively. The inferred relationship among the tribes and informally recognized major clades within Apioideae is presented.

A broad overview of the current state of taxonomic knowledge on the Apiaceae of Sub-Saharan Africa and Madagascar is presented. Sub-Saharan Africa has about 69 indigenous genera in the family, with 38 of them endemic, while Madagascar has at least 16 genera, of which six are endemic. Many taxa are poorly known and show unusual combinations of character states. Generic delimitations have not yet reached stability but monographic work, in which morphological, anatomical and some chemical characters are rigorously analysed, is contributing steadily to an improved understanding of generic relationships. A preliminary cladistic analysis of some genera is presented, based on characters such as woodiness, leaf persistence, leaf type, dentate-serrate leaf margins, heteromorphous fruits and the co-occurrence of intrajugal and vallecular vittae. Despite poor resolution, the results consistently show that several African and Madagascan genera are basal to the rest of the Apiaceae. The subfamily Saniculoideae Burnett always appears in a basal position, in close association with anomalous genera such as Lichtensteinia Cham. & Schltdl., Polemanniopsis B. L. Burtt, Steganotaenia Hoscht. and Pseudocarum C. Norman. These genera are clearly central to a better understanding of the early evolution of the family and also to an ultimate improvement of Drude's (1898) classification system.

Recent molecular studies indicate that the araliaceous tribes Myodocarpeae R. Vig. (Delarbrea Vieill., Pseudosciadium Baill. and Myodocarpus Brongn. & Gris.) and Mackinlayeae R. Vig. (Apiopetalum Baill., Mackinlaya F. Muell. and several genera of Hydrocotyloideae Link (Apiaceae)) comprise basally branching lineages within Apiales, an interpretation consistent with data from morphology and wood anatomy. Comparison of selected features in these genera, and in close relatives of Apiales, suggests that ancestral character states for the order may include: simple leaves, inflorescences in panicles of umbellules, flowers with articulated pedicels and a bicarpellate gynoecium, an andromonoecious, duodichogamous sexual system, septate fibres, the absence of radial canals, and the presence of paratracheal axial parenchyma in the wood.

Two new Umbelliferae species from S Anatolia are described and illustrated: Chaerophyllum aksekiense A. Duran & Duman and Tordylium ketenoglui Duman & A. Duran.