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Based on new studies on style morphology of basal subfamilies and tribes of Asteraceae (Barnadesioideae, Famatinanthoideae, Mutisioideae, Stifftioideae, Wunderlichioideae, Gochnatioideae, Hecastocleidoideae), we establish 15 style types in view of shape, bifurcation and distribution of stylar hairs and stigmatic tissue. From the stylar characters and observing different anthetic stages of the proterandrous flowers, we inferred the mechanisms of secondary pollen presentation. The high diversity of stylar shapes in the basal groups of Asteraceae is remarkable. In the most basal subfamily Barnadesioideae, the stylar surface is smooth or, at most, papillate and secondary pollen presentation is either a deposition/primitive brushing or a pump mechanism. Considering Calyceraceae (deposition mechanism) as sister group, we conclude that presumably a deposition/primitive brushing mechanism is the beginning of all secondary pollen presentations in Asteraceae. Whereas in the higher Asteraceae both the brushing and pump mechanisms function perfectly, in some lower Asteraceae, the mechanisms work less efficiently regarding pollen release. The subfamily Mutisioideae is well-defined by the occurrence of true stylar hairs and the tribe Mutisieae by its stigmatic tissue on the margins of the stylar arms, confluent at their tips. The early step from a continuous stigma covering the whole inner surface of the stylar branches (as in most basal members) to a stigma arrangement in two separate lines (as in most Asteroideae) is realized in two ways: either by adhesion of the median ventral tissues of the stylar branches (e.g. Onoseris , Wunderlichia ) or by receptivity loss of the median tissues (e.g. Mutisia ). Our study supports further DNA-based clades by style morphology (e.g. Famatinanthoideae).

Barnadesioideae (94 species) is the sister subfamily to the rest of the Asteraceae (23,000 species). Pollen grains in this subfamily are structurally and sculpturally distinctive and diverse. Although pollen morphology has contributed to the taxonomy of the subfamily, there is a gap of knowledge concerning the evolution of the exine structure. This study aims at exploring the systematic and phylogenetic significance of optimizing selected pollen characters of Barnadesioideae on the latest molecular phylogenetic tree. Transmission electron microscope (TEM) observations on pollen of selected species, some of them never explored so far, show that the exine probably evolved from a thin pattern (ca. 1–3 μm), with a well-developed foot layer and solid and free columellae, present in sister family Calyceraceae, towards a thicker (> 6–11 μm) and a more complex columellate-granulate bilayered exine in Barnadesioideae (with very delicate columellae). The particular exine structure observed in the monotypic Schlechtendalia luzulaefolia, which combines compact and independent columellae (common in more derived Asteraceae) with a granular internal tectum as the inner ectexine layer (as in Barnadesioideae), reinforces its distant phylogenetic position within Barnadesioideae. More derived lineages within Asteraceae (e.g. Mutisioideae) retained some ancestral exine features although evolved an even thicker exine and a columellate trilayered exine (with robust columellae), rare in the angiosperm pollen grains. Fil: Tellería, María Cristina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Sistemática y Biología Evolutiva; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Palazzesi, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina Fil: Barreda, Viviana Dora. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentina

A backbone phylogeny that fully resolves all subfamily and deeper nodes of Asteraceae was constructed using 14 chloroplast DNA loci. The recently named genus Famatinanthus was found to be sister to the Mutisioideae-Asteroideae clade that represents more than 99% of Asteraceae and was found to have the two chloroplast inversions present in all Asteraceae except the nine genera of Barnadesioideae. A monotypic subfamily Famatinanthoideae and tribe Famatinantheae are named herein as new. Relationships among the basal lineages of the family were resolved with strong support in the Bayesian analysis as (Barnadesioideae (Famatinanthoideae (Mutisioideae (Stifftioideae (Wunderlichioideae-Asteroideae))))). Ancestral state reconstruction of ten morphological characters at the root node of the Asteraceae showed that the ancestral sunflower would have had a woody habit, alternate leaves, solitary capitulescences, epaleate receptacles, smooth styles, smooth to microechinate pollen surface sculpturing, white to yellow corollas, and insect-mediated pollination. Herbaceous habit, echinate pollen surface, pubescent styles, and cymose capitulescences were reconstructed for backbone nodes of the phylogeny corresponding to clades that evolved shortly after Asteraceae dispersed out of South America. No support was found for discoid capitula, multiseriate involucres or bird pollination as the ancestral character condition for any node. Using this more resolved phylogenetic tree, the recently described Raiguenrayun cura+. Mutisiapollis telleriae fossil should be associated to a more derived node than previously suggested when time calibrating phylogenies of Asteraceae. Fil: Panero, Jose L.. University of Texas; Estados Unidos Fil: Freire, Susana Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Botánica Darwinion. Academia Nacional de Ciencias Exactas, Físicas y Naturales. Instituto de Botánica Darwinion; Argentina Fil: Ariza Espinar, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Crozier, Bonnie S.. P.O. Box 8315. Santa Fe; Argentina Fil: Barboza, Gloria Estela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Catolica de Córdoba. Facultad de Ciencias Químicas; Argentina Fil: Cantero, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Río Cuarto. Facultad de Agronomía y Veterinaria; Argentina

Much of our knowledge of the past distribution and radiation of Asteraceae and allied families depends on the fossil pollen record. In recent years, new discoveries are coming to light from southern Africa, Australia, New Zealand, and southern South America (Patagonia). Unequivocally assigned morphotaxa from accurately dated sediments have permitted for the first time a comprehensive review of the past distribution of the most important core of the sunflower alliance of families (Menyanthaceae, Goodeniaceae, Calyceraceae and Asteraceae). The main goal of this contribution is to explore the major evolutionary radiation of the basal lineages of Asteraceae (Mutisioideae and Barnadesioideae) and allied relatives (Menyanthaceae, Goodeniaceae and Calyceraceae) on the basis of the worldwide fossil pollen records. Several taxa, which today are restricted to isolated geographic regions, were widespread in the Southern Hemisphere during Paleogene times. Menyanthaceae, Goodeniaceae and Mutisioideae (Asteraceae), for example, had a wide distribution over Gondwanan landmasses in the Oligocene and are now drastically reduced in their geographic range. Early Neogene records, in contrast, suggest extinction and diversification events that progressively led to the present day configuration. In broad terms, the distribution of Miocene fossils assigned to this clade (Barnadesioideae, Nassauvieae, and Calyceraceae) agrees with that of their present distribution. The major floristic turnovers coincided with the final isolation of Antarctica, leading to cooler, drier, and more seasonal climates and forced the evolution and distribution of these Gondwanan elements. Fil: Barreda, Viviana Dora. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Palazzesi, Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentina Fil: Tellería, María Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Sistemática y Biología Evolutiva; Argentina Fil: Katinas, Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina Fil: Crisci, Jorge Victor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Laboratorio de Sistemática y Biología Evolutiva; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División de Plantas Vasculares; Argentina