Dr. James Stephen Boatwright

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Dr. James Stephen Boatwright


Position: Senior Lecturer
Department: Biodiversity and Conservation Biology
Faculty: Faculty of Natural Sciences
Qualifications: B.Sc., B.Sc. honours, M.Sc., Ph.D.
My publications in this repository
More about me: here, and here
Tel: 021 959 2264
Fax: 021 959 2312
Email: jboatwright@uwc.ac.za

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Now showing 1 - 9 of 9
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    An invasive alien Proteaceae lures some, but not all nectar-feeding bird pollinators away from native Proteaceae in South African fynbos
    (Plant Biology, 2021) Boatwrigh, James
    Invasive alien plants often influence pollinator visitation to native plants when sharing pollinator guilds. It is of conservation concern when the invasive alien plant is characterized by floral resources that attract pollinators, thereby reducing the reproductive success of native species. This is well studied for insects, but whether the same is true for bird pollinators is largely unknown. We address this by considering the impact of an invasive alien plant (Banksia speciosa) on visitation rates of nectar-feeding bird pollinators to native Protea compacta in the Cape Floristic Region of South Africa. We determined bird pollinator visitation rate to B. speciosa and P. compacta over 21 h of observation at three sites. We also quantified how visitation rate influenced reproductive success of both study species through different breeding experiments. • Sugarbird visitation to P. compacta was significantly lower in the presence of B. speciosa, while there was no effect for sunbirds as they mostly avoided B. speciosa. Protea compacta had higher nectar volumes and sucrose per flower than B. speciosa. Sucrose per hectare was higher in all P. compacta plots compared to B. speciosa. Neither study species is pollen limited and they are self-compatible to some extent. But pollinator visitation enhanced seed production in both species. We show here that the invasive alien B. speciosa flowers attract sugarbirds – but not sunbirds – away from native P. compacta. The long-term effect of reduced pollinator visitation may reduce the fitness of P. compacta, but the long-term demographic impact is unknown and would require further study.
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    Hitting the right target: taxonomic challenges for, and of, plant invasions
    (Oxford University Press, 2013) Pysek, Petr; Hulme, Philip E.; Meyerson, Laura A.; Smith, Gideon F.; Boatwright, James S.; Crouch, Neil R.; Figueiredo, Estrela; Foxcroft, Llewellyn C.; Jarosık, Vojtech; Richardson, David M.; Suda, Jan; Wilson, John R.U.
    This paper explores how a lack of taxonomic expertise, and by implication a dearth of taxonomic products such as identification tools, has hindered progress in understanding andmanaging biological invasions. It also explores how the taxonomic endeavour could benefit from studies of invasive species. We review the literature on the current situation in taxonomy with a focus on the challenges of identifying alien plant species and explorehowthis has affected the study of biological invasions. Biosecurity strategies, legislation dealing with invasive species, quarantine, weed surveillance and monitoring all depend on accurate and rapid identification of non-native taxa. However, such identification can be challenging because the taxonomic skill base in most countries is diffuse and lacks critical mass. Taxonomic resources are essential for the effective management of invasive plants and incorrect identifications can impede ecological studies. On the other hand, biological invasions have provided important tests of basic theories about species concepts. Better integration of classical alpha taxonomy and modern genetic taxonomic approaches will improve the accuracy of species identification and further refine taxonomic classification at the level of populations and genotypes in the field and laboratory. Modern taxonomy therefore needs to integrate both classical and new concepts and approaches. In particular, differing points of view between the proponents of morphological and molecular approaches should be negotiated because a narrow taxonomic perspective is harmful; the rigour of taxonomic decision- making clearly increases if insights from a variety of different complementary disciplines are combined and confronted. Taxonomy plays a critical role in the study of plant invasions and in turn benefits from the insights gained from these studies.
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    Towards a new classification system for legumes: Progress report from the 6th International Legume Conference
    (Elsevier, 2013) Borges, L.; Bruneau, Anne; Boatwright, James S.; and 29 other
    Legume systematists have been making great progress in understanding evolutionary relationships within the Leguminosae (Fabaceae), the third largest family of flowering plants. As the phylogenetic picture has become clearer, so too has the need for a revised classification of the family. The organization of the family into three subfamilies and 42 tribes is outdated and evolutionarily misleading. The three traditionally recognized subfamilies, Caesalpinioideae, Mimosoideae, and Papilionoideae, do not adequately represent relationships within the family. The occasion of the Sixth International Legume Conference in Johannesburg, South Africa in January 2013, with its theme “Towards a new classification system for legumes,” provided the impetus to move forward with developing a new classification. A draft classification, based on current phylogenetic results and a set of principles and guidelines, was prepared in advance of the conference as the basis for discussion. The principles, guidelines, and draft classification were presented and debated at the conference. The objectives of the discussion were to develop consensus on the principles that should guide the development of the classification, to discuss the draft classification's strengths and weaknesses and make proposals for its revision, and identify and prioritize phylogenetic deficiencies that must be resolved before the classification could be published. This paper describes the collaborative process by a large group of legume systematists, publishing under the name Legume Phylogeny Working Group, to develop a new phylogenetic classification system for the Leguminosae. The goals of this paper are to inform the broader legume community, and others, of the need for a revised classification, and spell out clearly what the alternatives and challenges are for a new classification system for the family.
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    Two new species of Trachyandra sect. Liriothamnus (Xanthorrhoeaceae, Asphodeloideae) from the Western and Eastern Cape Provinces of South Africa
    (2013) Boatwright, James S.; Manning, John C.
    Trachyandra eriocarpa and T. bulbosa are two new species from Northern and Eastern Cape Provinces of South Africa. They are placed in T. sect. Liriothamnus based on their wiry roots, the cataphylls not forming membranous collars, and the remains of the outer leaves forming a fibrous collar. Trachyandra eriocarpa from the Great Winterberg in Eastern Cape is recognised by its unusual, villous ovary and capsules; and T. bulbosa from north of Springbok in Northern Cape by the irregular, bulbous rhizome, microscopically puberulous leaves and maculate tepals.
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    Felicia douglasii (Asteraceae-Astereae), a distinctive new species from the Cape Floristic Region, South Africa
    (Elsevier, 2017) Manning, John C.; Magee, Anthony R.; Boatwright, James S.
    Felicia Cass. (Asteraceae) is the largest of the African members of tribe Astereae, and comprises ±90 species from southern and tropical Africa to Arabia. As currently circumscribed, it is rather weakly diagnosed by the herbaceous or shrubby habit, mostly radiate capitula with epaleate receptacle, ± concolorous rays, mostly bisexual disc florets, and eglandular cypselas with several scabrid or barbellate pappus bristles (Grau, 1973; Herman et al., 2000; Manning and Goldblatt, 2012).
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    A global infrageneric classification system for the genus Crotalaria (Leguminosae) based on molecular and morphological evidence
    (Botanischer Garten und Botanisches Museum, 2013) le Roux, Marianne M.; Boatwright, James S.; van Wyk, Ben-Erik
    Crotalaria is a large genus of 702 species with its centre of diversity in tropical Africa and Madagascar and secondary radiations in other parts of the world. The current infrageneric classification system is based on morphological and morphomet- ric studies of the African taxa only and is here re-evaluated using a phylogenetic approach. DNA sequences derived from the nuclear ITS and the plastid matK, psbA-trnH and rbcLa markers were analyzed using parsimony and model-based (Bayesian) approaches. The resultant molecular phylogeny allowed for a new interpretation of diagnostically important morphological characters, including specialisations of the calyx, keel, standard petal and style, which are variously convergent in several unrelated infrageneric groups. Of particular interest is the congruence between the new phylogeny and the distribution of stand- ard petal callosity types. A sectional classification system for the entire genus is proposed for the first time. The new system that is formalised here comprises eleven sections: Amphitrichae, Calycinae, Crotalaria, Geniculatae, Glaucae, Grandiflorae, Hedriocarpae, Incanae, Schizostigma, Borealigeniculatae and Stipulosae. Sectional limits of the Geniculatae, Calycinae and Crotalaria are modified. The subsections Stipulosae, Glaucae and Incanae are raised to sectional level, while some groups previously recognized as subsections are abandoned due to non-monophyly (subsections Chrysocalycinae, Hedriocarpae, Macrostachyae and Tetralobocalyx). Two new sections are recognized, Amphitrichae and Borealigeniculatae.
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    A taxonomic revision of the Pteronia camphorate group (Astereae, Asteraceae)
    (Elsevier, 2017) Bello, A.O.; Boatwright, James S.; Tilney, P.M.; Van der Bank, M.; Magee, Anthony R.
    As a first step towards a comprehensive revision of Pteronia (Asteraceae, Astereae), we present here a taxonomic treatment of the Pteronia camphorata group, in which we recognise three species. The group includes the type species P. camphorata (an important medicinal plant) and is easily distinguished from the rest of the genus by the glabrous rather than glandular or variously pilose cypselas. The lectotype of P. camphorata has involucral bracts with entire margins and long acuminate apices, both diagnostic characters for P. stricta. As such P. stricta is here reduced into synonymy with P. camphorata and the next available name, P. aspera Thunb, reinstated to accommodate the species heretofore treated as P. camphorata. Three varieties within Pteronia camphorata had been previously recognised (var. armata, var. laevigata and var. longifolia). The characters distinguishing var. armata were found to be continuous with the variation observed within var. longifolia. The third infraspecific taxon, var. laevigata, was however found to be distinct and is therefore recognised here as a new species, P. cederbergensis Bello, Magee & Boatwr. It is readily distinguished by the glabrous branches, opposite to sub-opposite somewhat succulent leaves, the 2-seriate pappus and larger, obclavate cypselas. Transverse sections of the leaves and cypselas were also examined and provide additional differences between the three recognised species.
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    Reconstructing the deep-branching relationships of the papilionoid legumes
    (Elsevier, 2013) Cardoso, D.; Pennington, R.T.; de Queiroz, L.P.; Boatwright, James S.; van Wyk, Brian Eduard; Wojciechowski, M.F.; Lavin, M.
    Resolving the phylogenetic relationships of the deep nodes of papilionoid legumes (Papilionoideae) is essential to understanding the evolutionary history and diversification of this economically and ecologically important legume subfamily. The early-branching papilionoids include mostly Neotropical trees traditionally circumscribed in the tribes Sophoreae and Swartzieae. They are more highly diverse in floral morphology than other groups of Papilionoideae. For many years, phylogenetic analyses of the Papilionoideae could not clearly resolve the relation- ships of the early-branching lineages due to limited sampling. In the eight years since the publication of Legumes of the World, we have seen an extraordinary wealth of new molecular data for the study of Papilionoideae phylogeny, enabling increasingly greater resolution and many surprises. This study draws on recent molecular phylogenetic studies and a new comprehensive Bayesian phylogenetic analysis of 668 plastid matK sequences. The present matK phylogeny resolves the deep-branching relationships of the papilionoids with increased support for many clades, and suggests that taxonomic realignments of some genera and of numerous tribes are necessary. The potentially earliest-branching papilionoids fall within an ADA clade, which includes the recircumscribed monophyletic tribes Angylocalyceae, Dipterygeae, and Amburanae. The genera Aldina and Amphimas represent two of the nine main but as yet unresolved lineages comprising the large 50-kb inversion clade. The quinolizidine-alkaloid-accumulating Genistoid s.l. clade is expanded to include Dermatophyllum and a strongly supported and newly circumscribed tribe Ormosieae. Sophoreae and Swartzieae are dramatically reorganized so as to comprise mono-phyletic groups within the Core Genistoid clade and outside the 50-kb inversion clade, respectively. Acosmium is excluded from the Genistoids s.l. and strongly resolved within the newly circumscribed tribe Dalbergieae. By providing a better resolved phylogeny of the earliest-branching papilionoids, this study, in combination with other recent evidence, will lead to a more stable phylogenetic classification of the Papilionoideae.
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    Phylogenetic placement and generic re-circumscriptions of the multilocular genera Arenifera, Octopoma and Schlechteranthus (Aizoaceae: Ruschieae): Evidence from anatomical, morphological and plastid DNA data
    (International Association for Plant Taxonomy (IAPT), 2016) Powell, Robyn F.; Boatwright, James S.; Klak, Cornelia; Magee, Anthony R.
    "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."