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While conducting phylogenetic analyses of sequence-capture data of Australian members of Asteraceae tribe Astereae, we found that Elachanthus pusillus F.Muell., Isoetopsis graminifolia Turcz. and Kippistia suaedifolia F.Muell. formed a clade with Minuria. We, therefore, conducted an analysis focused on this clade, but with replicate samples of the three smaller genera, and confirmed our results. Kippistia had been synonymised under Minuria between 1876 and 1980, when it was reinstated. Elachanthus and Isoetopsis had not previously been suggested to be part of Minuria , and, indeed, Isoetopsis had been considered so morphologically divergent that even its tribal affiliations were long controversial. However, on closer examination, Elachanthus and Isoetopsis are strikingly similar to Minuria , especially in cypsela and pappus morphology. The evolution of both genera from a common ancestor in Minuria appears plausible in the light of their overall similarity to annual species of that genus such as M. annua , their multiple uniform rows of herbaceous phyllaries with scarious margins, a pappus of scales v. the tendency of Minuria to form pappi with scale-like bases, female outer and male inner florets, and a cypsela indumentum shared with some species of Minuria. We propose the following three new combinations under Minuria : M. pusilla , M. glabra and M. graminifolia. We conducted a phylogenetic analysis of Minuria and related genera and found that Elachanthus , Isoetopsis , and Kippistia phylogenetically nested in Minuria. Before 1980, Kippistia had long been considered part of Minuria. Morphological examination showed many similarities between Eleachanthus , Isoetopsis , and annual species of Minuria. We publish new combinations for four species, synonymising the three smaller genera. (Image credit: Alexander Schmidt-Lebuhn.) This article belongs to the collection Genomics for Australian Plants. [ABSTRACT FROM AUTHOR]

The Senecio inaequidens – S. madagascariensis complex (Asteraceae: Senecioneae, subsequently "fireweed complex") is a group of six southern African species of Senecio, three of which are considered invasive in various parts of the world: S. madagascariensis in South America, Japan, Australia, and the Hawaiian Islands, S. skirrhodon in New Zealand, and S. inaequidens in Mexico and Europe. Morphological plasticity and historically limited access to reliable information in the introduced ranges have led to taxonomic confusion in many countries, where the weedy populations have been classified under changing names and sometimes erroneously considered to be native species. This confusion has hampered research into management options such as biological control. Recently, uncertainty has arisen about whether only one or two species of the fireweed complex are present in New Zealand. To resolve this question and test the utility of multi-locus sequence capture data for the understanding of the complex, we produced a first dataset of hundreds of genes for four of its species with a focus on S. madagascariensis and S. skirrhodon. Both species were found to be present in the North Island of New Zealand, with S. madagascariensis widespread in the Northland region and S. skirrhodon present at both sites sampled in the southern half of North Island. Our results show that sequence capture data provide high levels of confidence and resolution even at shallow phylogenetic levels, which will enable a greater understanding of the fireweed complex and its invasion history as the dataset is expanded. [ABSTRACT FROM AUTHOR]

Tribe Anthemideae (Asteraceae) is represented in Australia by only nine indigenous species of Cotula and Leptinella. The generic placement of Cotula alpina (Hook.f.) Hook.f. is considered problematic, because it shares the stoloniferous and scapose habit of Leptinella, but lacks corollas in female florets, a trait traditionally considered defining of Cotula. A previous phylogenetic analysis of Leptinella using ITS and chloroplast data showed that the species nested in that genus, but some uncertainty remained because of incomplete sequence data and missing cytological information, and no taxonomic change was made. Here, we use target-capture data from three different sequencing initiatives to reconstruct a phylogeny of Australian native and introduced Anthemideae to resolve this outstanding question. We confirm previous results with a high degree of support and formally transfer Cotula alpina to the genus Leptinella. A lectotype is selected for the basionym, Ctenosperma alpinum Hook.f. [ABSTRACT FROM AUTHOR]

Premise of research. Computer vision has the potential to become a transformative identification tool in biodiversity research and collections management, allowing high-throughput identification and removing the need for nonexpert end users to understand technical terminology. A major bottleneck for taxonomists is the generation of sufficient numbers of training images. Contemporary large-scale imaging projects of herbaria provide an increasing number of specimen photos, but whole-sheet images are not directly suitable for training image classification models targeted at individual taxonomically informative characters. Methodology. Here, we illustrate a time- and labor-efficient approach for generating training libraries for image classification from photos of herbarium sheets. It involves the annotation of specimen images with bounding boxes using open-source software and automated cropping of annotations with a custom script to produce the training library. We demonstrate the approach on the flower heads of a genus of Asteraceae comprising eight taxa, six species and two nontypus varieties. Pivotal results. After generating 816 training images from 33 specimen photos with a time investment of only ∼90 min, we trained an image classification model that achieved 98.2% precision and recall. Conclusions. The demonstrated approach allows taxonomists to use digitized herbarium specimens to produce training libraries for image classification models within hours. We expect that computer vision will increasingly become a part of taxonomic practice. [ABSTRACT FROM AUTHOR]