Extrafloral nectaries in Leguminosae: phylogenetic distribution, morphological diversity and evolution

Extrafloral nectaries (EFNs) mediating ecologically important ant-plant protection mutualisms are especially common and unusually diverse in the Leguminosae. We present the first comprehensively curated list of legume genera with EFNs, detailing and illustrating their systematic and phylogenetic distributions, locations on the plant, morphology and anatomy, based on a unified classification of EFN categories and a time-calibrated phylogeny incorporating 710 of the 768 genera. This new synthesis, the first since McKey (1989)?s seminal paper, increases the number of genera with EFNs to 152 (20% of legumes), distributed across subfamilies Cercidoideae (1), Detarioideae (19), Caesalpinioideae (87) and Papilionoideae (45). EFNs occur at nine locations, and are most prevalent on vegetative plant parts, especially leaves (74%) and inflorescence axes (26%). Four main categories (with eight subcategories) are recognized: formless, trichomatic (exposed, hollow), parenchymatic (embedded, pit, flat, elevated) and abscission zone EFNs (non-differentiated, swollen scars). Phylogenetic reconstruction of EFNs suggests independent evolutionary trajectories of different EFN types, with elevated EFNs restricted almost exclusively to Caesalpinioideae (where they underwent spectacular morphological disparification), flat EFNs in Detarioideae, swollen scar EFNs in Papilionoideae, and Cercidoideae is the only subfamily bearing intrastipular EFNs. We discuss the complex evolutionary history of EFNs and highlight future research directions.Fil: Marazzi, Brigitte. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina. Natural History Museum Of Canton Ticino; SuizaFil: González, Ana María. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Delgado Salinas, Alfonso. Universidad Nacional Autónoma de México; MéxicoFil: Luckow, Melissa A.. Cornell University; Estados UnidosFil: Ringelberg, Jens J.. Universitat Zurich; SuizaFil: Hughes, Colin E.. Universitat Zurich; Suiz

Hybrid capture of 964 nuclear genes resolves evolutionary relationships in the mimosoid legumes and reveals the polytomous origins of a large pantropical radiation

PREMISE Targeted enrichment methods facilitate sequencing of hundreds of nuclear loci to enhance phylogenetic resolution and elucidate why some parts of the “tree of life” are difficult (if not impossible) to resolve. The mimosoid legumes are a prominent pantropical clade of ~3300 species of woody angiosperms for which previous phylogenies have shown extensive lack of resolution, especially among the species‐rich and taxonomically challenging ingoids. METHODS We generated transcriptomes to select low‐copy nuclear genes, enrich these via hybrid capture for representative species of most mimosoid genera, and analyze the resulting data using de novo assembly and various phylogenomic tools for species tree inference. We also evaluate gene tree support and conflict for key internodes and use phylogenetic network analysis to investigate phylogenetic signal across the ingoids. RESULTS Our selection of 964 nuclear genes greatly improves phylogenetic resolution across the mimosoid phylogeny and shows that the ingoid clade can be resolved into several well‐supported clades. However, nearly all loci show lack of phylogenetic signal for some of the deeper internodes within the ingoids. CONCLUSIONS Lack of resolution in the ingoid clade is most likely the result of hyperfast diversification, potentially causing a hard polytomy of six or seven lineages. The gene set for targeted sequencing presented here offers great potential to further enhance the phylogeny of mimosoids and the wider Caesalpinioideae with denser taxon sampling, to provide a framework for taxonomic reclassification, and to study the ingoid radiation

Chromosome Studies in Asteraceae from the United States, Mexico, the West Indies, and South America

Chromosome counts of Asteraceae are reported from Mexico, the United States, the West Indies, Peru, and Bolivia. First counts are reported for 27 species, eight infraspecific taxa, and three interspecific hybrids in Brickellia , Chrysanthellum, Cirsium, Egletes, Erigeron, Flaveria, Gnaphalium, Heterotheca, Hieracium, Hymenothrix, Koanophyllon, Layia, Lessingia, Pectis, Sclerocarpus, Stuessya, Tagetes and Wedelia. Counts are also reported for 196 taxa or hybrids for which chromosome numbers have been published previously. Of these, nine are new numbers. Taxonomic implications of certain counts are discussed

CYMOPHORA (ASTERACEAE: HELIANTHEAE) RETURNED TO TRIDAX

Volume: 34Start Page: 354End Page: 35

Extrafloral nectaries in Leguminosae: phylogenetic distribution, morphological diversity and evolution

Extrafloral nectaries (EFNs) mediating ecologically important ant–plant protection mutualisms are especially common and unusually diverse in the Leguminosae. We present the first comprehensively curated list of legume genera with EFNs, detailing and illustrating their systematic and phylogenetic distributions, locations on the plant, morphology and anatomy, on the basis of a unified classification of EFN categories and a time-calibrated phylogeny, incorporating 710 of the 768 genera. This new synthesis, the first since Mckey (1989)’s seminal paper, increases the number of genera with EFNs to 153 (20% of legumes), distributed across subfamilies Cercidoideae (1), Detarioideae (19), Caesalpinioideae (87) and Papilionoideae (46). EFNs occur at nine locations, and are most prevalent on vegetative plant parts, especially leaves (74%) and inflorescence axes (26%). Four main categories (with eight subcategories) are recognised and include the following: formless, trichomatic (exposed, hollow), parenchymatic (embedded, pit, flat, elevated) and abscission zone EFNs (non-differentiated, swollen scars). Phylogenetic reconstruction of EFNs suggests independent evolutionary trajectories of different EFN types, with elevated EFNs restricted almost exclusively to Caesalpinioideae (where they underwent spectacular morphological disparification), flat EFNs in Detarioideae, swollen scar EFNs in Papilionoideae, and Cercidoideae is the only subfamily bearing intrastipular EFNs. We discuss the complex evolutionary history of EFNs and highlight future research directions

RELATIONSHIPS AMONG GENERA OF THE INFORMAL DICHROSTACHYS AND LEUCAENA GROUPS (MIMOSOIDEAE) INFERRED FROM NUCLEAR RIBOSOMAL ITS SEQUENCES

Abstract Previous attempts to elucidate sister group relationships among the genera of the informal Dichrostachys and Leucaena groups of the tribe Mimoseae have been hampered by incomplete taxon sampling, incomplete knowledge and poor circumscription of a number of the constituent genera, primary reliance on a limited set of morphological characters, and uncertainty about sister group relationships across the Mimoseae as a whole. Here we present a densely sampled informal Dichrostachys and Leucaena group analysis that includes all the constituent genera and 72 of the 91 species using a new DNA sequence data set from the nrDNA 5.8S and flanking internal transcribed spacer regions (ITS1 and ITS2). This analysis confirms the previously proposed realignment of the informal Leucaena group to include Leucaena, Desmanthus, Schleinitzia and Kanaloa, and the Dichrostachys group to include Dichrostachys, Gagnebina, Alantsilodendron and Calliandropsis, as well as the exclusion of Neptunia from these groups. The analysis also provides the first species-level molecular phylogeny for the genera of the Dichrostachys group, and species relationships within this group are discussed in relation to morphology and generic delimitation. The pattern of ITS variation within Desmanthus indicates incomplete sampling of ITS diversity limiting the usefulness of the current ITS gene tree to infer species relationships within the genus

Uhl, Charles H.

Also available as a printed booklet and from the Dean of Faculty website https://theuniversityfaculty.cornell.edu/Memorial Statement for Charles H. Uhl, who died in 2010. The memorial statements contained herein were prepared by the Office of the Dean of the University Faculty of Cornell University to honor its faculty for their service to the university

Uhl, Natalie W.

Also available as a printed booklet and from the Dean of Faculty website https://theuniversityfaculty.cornell.edu/Memorial Statement for Natalie W. Uhl, who died in 2017. The memorial statements contained herein were prepared by the Office of the Dean of the University Faculty of Cornell University to honor its faculty for their service to the university