A.R. Magee

Generic delimitations and relationships of the Cape genera Capnophyllum, Dasispermum, and Sonderina, the North African genera Krubera and Stoibrax, and a new monotypic genus of the subfamily Apioideae (Apiaceae)

Abstract Generic circumscriptions and phylogenetic relationships of the Cape genera Capnophyllum, Dasispermum, and Sonderina are explored through parsimony and Bayesian inference analyses of nrDNA ITS and cpDNA rps16 intron sequences, morphology and combined molecular and morphological data. The relationship of these genera with the North African genera Krubera and Stoibrax is also assessed. Analyses of both molecular data sets place Capnophyllum, Dasispermum, Sonderina, and the only southern African species of Stoibrax (S. capense) within the newly recognized Lefebvrea clade of tribe Tordylieae. Capnophyllum is strongly supported as monophyletic and is distantly related to Krubera. The monotypic genus Dasispermum and Stoibrax capense are embedded within a paraphyletic Sonderina. This complex is distantly related to the North African species of Stoibrax in tribe Apieae, in which the type species, Stoibrax dichotomum, occurs. Consequently, Dasispermum is expanded to include both Sonderina and Stoibrax capense. New combinations are formalized for Dasispermum capense, D. hispidum, D. humile, and D. tenue. An undescribed species from the Tanqua Karoo in South Africa is also closely related to Capnophyllum and the Dasispermum—Sonderina complex. The genus Scaraboides is described herein to accommodate the new species, S. manningii. This monotypic genus shares the dorsally compressed fruit and involute marginal wings with Capnophyllum, but is easily distinguished by its erect branching habit, green leaves, scabrous umbels, and fruit with indistinct median and lateral ribs, additional solitary vittae in each marginal wing, and parallel, closely spaced commissural vittae. Despite the marked fruit similarities with Capnophyllum, analyses of DNA sequence data place Scaraboides closer to the Dasispermum—Sonderina complex, with which it shares the erect habit, green (nonglaucous) leaves, and scabrous umbels.

A Taxonomic Revision of the Woody South African Genus Notobubon (Apiaceae: Apioideae)

Abstract A comprehensive taxonomic revision of the genus Notobubon (Apiaceae) is presented. Twelve woody evergreen species are recognised, all (with the exception of N. laevigatum) endemic to the Cape Floristic Region of South Africa. The taxonomy of these prominent, though poorly collected, species has until now been problematic. They are distinguished from one another by their habit (size and branching pattern), the overall shape, size, and colour of the ultimate leaflet segments, the inflorescence structure (peduncle length, number, and length of rays in the primary umbel), the fruit morphology (fruit size, presence or absence of wings), and the fruit anatomy (symmetry of the mericarps, presence or absence of additional rib vittae, size of commissural vittae). Species relationships are assessed in the form of a cladistic analysis of 26 morphological characters, resulting in a well-resolved phylogenetic hypothesis. A comprehensive key to the species, their correct nomenclature, and typification, together with descriptions and known geographical distribution for all the species are presented and illustrated.

A Taxonomic Revision Of the South African Endemic Genus Arctopus (Apiaceae, Saniculoideae)1

Abstract The genus Arctopus L. is revised. It is an anomalous member of the family Apiaceae, with several unusual morphological characters such as the prostrate spiny leaves, thick resinous tuberous roots, sessile female flowers with a homochlamydeous perianth, and pseudanthia formed by distinctive bracteoles. The three species of Arctopus were found to differ mainly in their reproductive morphologies, being easily distinguishable by the large involucral bracteoles that surround the female pseudanthia. The anatomy of the petiole as well as the morphology of the inflexed spines and leaf margins were also found to be useful diagnostic characters and are illustrated and discussed. Possible phylogenetic relationships were explored using both morphological and DNA sequence data (ITS). A formal taxonomic treatment is presented, including a key to the species, correct nomenclature, typification, descriptions, illustrations, and distribution maps.

Ezosciadium (Apiaceae): a taxonomic revision of yet another early diverging South African apioid genus

The hitherto poorly known Cape endemic genus Ezosciadium (Apiaceae) is revised. This genus is highly distinctive and can be distinguished from other annual genera of the region by its pilose vegetative and reproductive organs, the sessile compound umbels with conspicuously unequal rays, the non-inflexed petal tips, the relatively small, highly-inflexed stamens which appear almost sessile, and the prominent carpophores which persist on the plant. The fruit are unusual in the presence of druse crystals around the carpophore and tanniniferous substances in the epidermal cells of the ribs. The phylogenetic position of the genus within the subfamily Apioideae was assessed using rbcL, rps16 intron (2 new accessions) and nrITS (1 new accession) sequence data. Ezosciadiumcapense was found to form part of an early diverging lineage within the subfamily, sister group to the Annesorhiza clade and possibly also closely related to the genera Molopospermum and Astydamia. A comprehensive taxonomic revision, including typification, detailed descriptions, geographical range and illustrations, is presented.

A Taxonomic Revision of the Annesorhiza triternata Group (Apiaceae, Apioideae): The Transfer of Peucedanum triternatum and P. filicaule and the Description of Five New Species

Abstract A taxonomic revision of the Annesorhiza triternata group is presented. The group is composed of seven species all endemic to the Cape Floristic Region of South Africa. Two of the species had previously been assigned to the genus Peucedanum, as P.filicauk and P. triternatum, based on the marginally winged and dorsally ribbed homomericarpic fruits. They are here transferred to the genus Annesorhiza based on the periodically replaced fleshy roots, hysteranthous leaves, and fruits that have an oblong, more or less isodiametric body, a narrow commissure, and druse crystals scattered throughout the mesocarp. In addition, five new species clearly allied to A.filicaulis and A. triternata are described herein, viz. A. bracteosa, A. elsiae, A. laticostata, A. radiata , and A. refracta. The group is distinguished from other species in the genus by less sturdy synflorescences, ternate leaves with linear ultimate leaflets (except A. refracta), distinctly branched resin ducts in the petals (except A. filicaulis, A. laticostata and A. radiata), and mericarps with marginal wings and dorsal ribs (except A. elsiae). A comprehensive key to the seven species is provided together with an updated taxonomy with detailed morphological descriptions, a lectotypification, diagnostic illustrations, and maps of known geographical distributions.

Billburttia, a new genus of Apiaceae (tribe Apieae) endemic to Madagascar.

The genus Billburttia is described to include two new species endemic to Madagascar, B. capensoides and B. vaginoides. Both species were tentatively placed within the problematic genus Peucedanum L. (as Peucedanum sp. A and Peucedanum sp. B) based on their dorsally compressed fruits lacking prominent dorsal ribs and with winged marginal ribs. Recently, however, the African members of Peucedanum have been shown to be only distantly related to the type of the genus and have therefore been segregated into six African endemic genera. While the Malagasy species appear superficially similar to members from one of these segregate genera, viz. Notobubon, they differ markedly in their fruit anatomical characters, notably a narrower commissure, six commissural vittae, vascular tissue in the tip of the ribs and sphaerocrystals distributed in and around the epidermis. The latter two characters apparently represent apomorphies for Billburttia. The non-peucedanoid affinity of the genus, as suggested by the fruit anatomical data, was confirmed using ITS and rps16 intron sequences. Both parsimony and Bayesian analyses of these data place Billburttia within the tribe Apieae of subfamily Apioideae and not closely related to either Peucedanum (Selineae) or the African peucedanoid genera (Lefebvrea clade of Tordylieae).

Producing a plant diversity portal for South Africa

The National Research Foundation (grant reference number: UID92629) and Royal Society (grant reference number: SA140038) are thanked for the funding that was awarded to host an e-Flora workshop in South Africa.

Lasiosiphon esterhuyseniae (Thymelaeaceae: Thymelaeoideae), a new species from Northern Cape (South Africa), and the transfer of two additional southern African species to the genus

SummaryWe describe a new species, Lasiosiphon esterhuyseniae Magee & J. C. Manning, for a rigid, densely branched shrublet from the Kalahari Region, Northern Cape, South Africa. Due to the relatively restricted range, the lack of recent records (the most recent from 1940) and the lack of information regarding its palatability we recommend an IUCN status of Data Deficient. Two additional southern African taxa with the inflorescence and floral morphology diagnostic for Lasiosiphon, but currently still included in Gnidia, were encountered and new combinations for these species are provided, viz. Lasiosiphon microcephalus (Meisn.) J. C. Manning & Magee and L. rubescens (B. Peterson) J. C. Manning & Magee. As a result 29 species of Lasiosiphon are now recognised in southern Africa and a complete listing of these species is provided.

Phylogenetic placement and generic re-circumscriptions of the multilocular genera Arenifera, Octopoma and Schlechteranthus (Aizoaceae: Ruschieae): Evidence from anatomical, morphological and plastid DNA data

Ruschieae is the largest tribe in the highly speciose subfamily Ruschioideae (Aizoaceae). A generic-level phylogeny for the tribe was recently produced, providing new insights into relationships between the taxa. Octopoma and Arenifera are woody shrubs with multilocular capsules and are distributed across the Succulent Karoo. Octopoma was shown to be polyphyletic in the tribal phylogeny, but comprehensive sampling is required to confirm its polyphyly. Arenifera has not previously been sampled and therefore its phylogenetic placement in the tribe is uncertain. In this study, phylogenetic sampling for nine plastid regions (atpB-rbcL, matK, psbJ-petA, rpl16, rps16, trnD-trnT, trnL-F, trnQUUG-rps16, trnS-trnG) was expanded to include all species of Octopoma and Arenifera, to assess phylogenetic placement and relationships of these genera. Three phylogenetic analyses were carried out, maximum parsimony, maximum likelihood and Bayesian inference. Leaf anatomical sections were studied to further inform generic circumscriptions. The phylogenies showed Octopoma to be polyphyletic, with the type, O. octojuge, and the related O. nanum, resolved as sister to Zeuktophyllum and Smicrostigma, while the other species were placed in the Conophytum-clade. Arenifera was also shown to be polyphyletic, with the type, A. pillansii, placed in the xeromorphic-clade, and the remainder of the species recovered among the Octopoma species in the Conophytum-clade (forming the Octopoma subglobosum–Arenifera spinescens subclade). Generic affinities of the O. subglobosum–A. spinescens subclade were assessed in relation to the sister taxon Schlechteranthus. The leaf anatomy was found to be informative within the study group. Bladder cells were observed in Arenifera pillansii, a hypodermis in Little Karoo Octopoma (O. octojuge, O. nanum, O. quadrisepalum) and epidermal cells forming blunt papillae in Schlechteranthus and the O. subglobosum–A. spinescens subclade. Upon assessment of the anatomical, morphological and phylogenetic data, Schlechteranthus is here expanded to include the species in the O. subglobosum–A. spinescens subclade. Eight new combinations are made in Schlechteranthus. As a result, Arenifera is again monotypic and the circumscription of Octopoma is refined to include three species restricted to the Little Karoo. Two subgenera within Schlechteranthus s.l. (subg. Schlechteranthus, subg. Microphyllus) are erected to accommodate differences in leaf size, capsule size, closing body size and locule number.

Decoding Ice-plants: challenges associated with barcoding and phylogenetics in the diverse succulent family Aizoaceae

Aizoaceae is the largest succulent plant family in the world, including in excess of 1800 species. Despite its richness, a large proportion of its taxa are listed as data deficient and as such, has been identified as the top priority for taxonomic research in South Africa. Limitations to accurate taxonomic identification of taxa in the family may be partly attributed to the degree of technical knowledge required to identify taxa in the Aizoaceae. DNA barcoding may provide an alternative method of identification; however, the suitability of commonly used gene regions has not been tested in the family. Here, we analyse variable and parsimony informative characters (PIC), as well as the barcoding gap, in commonly used plastid regions (atpB-rbcL, matK, psbA-trnH, psbJ-petA, rpl16, rps16, trnD-trnT, trnL-trnF, trnQ-rps16, and trnS-trnG) and the nuclear region ITS (for Aizooideae only) across two subfamilies and two expanded clades within the Aizoaceae. The relative percentage of PIC was much greater in subfamilies Aizooideae and Mesembryanthemoideae than in Ruschioideae. Although nrITS had the highest percentage of PIC, barcoding gap analyses identified neither ITS nor any chloroplast region as suitable for barcoding of the family. From the results, it is evident that novel barcoding regions need to be explored within the Aizoaceae.