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This study presents an evaluation of the currently accepted sectional classification of the genus Anthurium Schott (Araceae) in light of a recently published molecular phylogeny for the group. In general, disagreements between these two occur because many diagnostic morphological characters used in the sectional classification turned out to be highly homoplasious within Anthurium, with multiple independent gains or losses of seemingly similar morphologies in distantly related clades. A new sectional classification of Anthurium that more accurately represents species relationships and the evolutionary history of the genus is much needed, and here we propose the first steps toward it. Results from this study suggest that out of the 18 sections and two series recognized in Anthurium, only seven of these groups are monophyletic (i.e., sections Andiphilum (Schott) Croat, Calomystrium (Schott) Engl., Dactylophyllium (Schott) Engl., Leptanthurium (Schott) Engl., Polyphyllium Engl., Tetraspermium (Schott) Engl., and the newly recognized section Multinervia (Croat) Carlsen & Croat, previously a series within section Pachyneurium (Schott) Engl.). All other sections are either not monophyletic or their monophyly could not be accurately tested. A complete revision of the sectional classification of Anthurium will require a more comprehensive taxon sampling and a better supported molecular phylogeny. [ABSTRACT FROM AUTHOR]

Inferring interfamilial relationships within the eudicot order Ericales has remained one of the more recalcitrant problems in angiosperm phylogenetics, likely due to a rapid, ancient radiation. As a result, no comprehensive time-calibrated tree or biogeographical analysis of the order has been published. Here, we elucidate phylogenetic relationships within the order and then conduct time-dependent biogeographical and diversification analyses by using a taxon and locus-rich supermatrix approach on one-third of the extant species diversity calibrated with 23 macrofossils and two secondary calibration points. Our results corroborate previous studies and also suggest several new but poorly supported relationships. Newly suggested relationships are: (1) holoparasitic Mitrastemonaceae is sister to Lecythidaceae, (2) the clade formed by Mitrastemonaceae + Lecythidaceae is sister to Ericales excluding balsaminoids, (3) Theaceae is sister to the styracoids + sarracenioids + ericoids, and (4) subfamilial relationships with Ericaceae suggest that Arbutoideae is sister to Monotropoideae and Pyroloideae is sister to all subfamilies excluding Arbutoideae, Enkianthoideae, and Monotropoideae. Our results indicate Ericales began to diversify 110 Mya, within Indo-Malaysia and the Neotropics, with exchange between the two areas and expansion out of Indo-Malaysia becoming an important area in shaping the extant diversity of many families. Rapid cladogenesis occurred along the backbone of the order between 104 and 106 Mya. Jump dispersal is important within the order in the last 30 My, but vicariance is the most important cladogenetic driver of disjunctions at deeper levels of the phylogeny. We detect between 69 and 81 shifts in speciation rate throughout the order, the vast majority of which occurred within the last 30 My. We propose that range shifting may be responsible for older shifts in speciation rate, but more recent shifts may be better explained by morphological innovation. [ABSTRACT FROM AUTHOR]

Premise of research. Campyloneurum is entirely Neotropical with about 60 generally accepted species. Although a prominent, mostly epiphytic genus in Neotropical forests, no research has been done previously on its phylogeny or character evolution.Methodology. We obtained sequence data from four plastid markers (rbcL, trnG-trnR, trnL-trnF, and rps4-trnS) of 44 species of Campyloneurum, or 73% of the species in the genus. The sequence data were analyzed using Bayesian and maximum likelihood methods. Herbarium specimens were examined to code morphological characters, and spores were imaged with the scanning electron microscope. Growth form and five morphological character states were optimized on the trees using parsimony.Pivotal results. We confirm most previous studies that Campyloneurum forms a clade with Microgramma and Niphidium. The three genera are generally characterized by simple entire leaves, areolate venation, and included veins within the areoles. Within Campyloneurum, seven main clades were recovered, some of which were defined by distinctive geography or morphological characters such as pruinose rhizomes, long-creeping rhizomes, or one-pinnate leaves. The spores were uniform and did not provide any grouping information. The genus has its highest endemism and diversity in the Andes, with the mountains of Costa Rica and Panama being a secondary center. A map is given showing the estimated species richness and percent endemism of Campyloneurum in different geographical regions of the Neotropics.Conclusions. This study presents the first phylogenetic analysis of Campyloneurum. The genus forms a clade with Microgramma and Niphidium. Within the genus, seven main clades were recognized, some of which are supported by distinctive morphological synapomorphies. A clade of five species is endemic to southeastern Brazil. Our tree suggests that many undescribed species occur in the genus, indicating the need for more taxonomic studies at the species level. [ABSTRACT FROM AUTHOR]

The Andean mountains of South America are the most species-rich biodiversity hotspot worldwide with c. 15% of the world's plant species, in only 1% of the world's land surface. Orchids are a key element of the Andean flora, and one of the most prominent components of the Neotropical epiphyte diversity, yet very little is known about their origin and diversification., We address this knowledge gap by inferring the biogeographical history and diversification dynamics of the two largest Neotropical orchid groups (Cymbidieae and Pleurothallidinae), using two unparalleled, densely sampled orchid phylogenies (including more than 400 newly generated DNA sequences), comparative phylogenetic methods, geological and biological datasets., We find that the majority of Andean orchid lineages only originated in the last 20-15 million yr. Andean lineages are derived from lowland Amazonian ancestors, with additional contributions from Central America and the Antilles. Species diversification is correlated with Andean orogeny, and multiple migrations and recolonizations across the Andes indicate that mountains do not constrain orchid dispersal over long timescales., Our study sheds new light on the timing and geography of a major Neotropical diversification, and suggests that mountain uplift promotes species diversification across all elevational zones. [ABSTRACT FROM AUTHOR]

As a step towards a revision of the sectional classification of Neotropical species of Habenaria, we focus here on section Pentadactylae. In its current delimitation, this is the largest of the 14 New World sections and embraces a group of 34 morphologically heterogeneous species. We expanded the sampling of Neotropical species currently placed in this section and performed Bayesian, maximum likelihood and parsimony analyses using nucleotide sequences from one nuclear (internal transcribed spacer, ITS) and three plastid ( mat K, trn K intron, rps16- trn K) DNA regions. In addition, morphological features of these species were reassessed. Based on our analyses, we propose that Habenaria section Pentadactylae should be recircumscribed to include only seven species: H. pentadactyla (the type species of the section), H. dutrae, H. ekmaniana, H. exaltata, H. henscheniana, H. megapotamensis and H. montevidensis. Thirty-two species previously assigned to the section grouped within unrelated clades and are therefore excluded from the section. There are no unambiguous morphological synapomorphies for the section, but the group can be confidently recircumscribed and identified on the basis of a combination of diagnostic morphological vegetative and floral characters. Morphological floral features in Habenaria montevidensis are distinct from those of other species in the section, probably as a result of a shift to diurnal pollinators. Following a taxonomic revision of the group, H. crassipes is placed under the synonymy of H. exaltata and neotypes are designated for H. crassipes, H. montevidensis and H. recta (= H. ekmaniana). All species in the section live in marshes or wet grasslands from northern Argentina to central Brazil; most species are concentrated in southern Brazil. Most species are probably rare, and five may be threatened according to the World Conservation Union ( IUCN) criteria. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175, 47-73. [ABSTRACT FROM AUTHOR]

The phylogenetic relationships of some Neotropical plant groups have proved to be different from expectation assuming plate tectonics as the underlying model, and these unanticipated relationships (and their timing) have required further work to explain how they came into existence. Well-known Neotropical families, such as Bromeliaceae and Cactaceae, have one to a few species in Africa, but these can be explained by recent long-distance dispersals; the estimated ages of the Transatlantic crown and stem clades of these families are of relatively recent origin, so long-distance dispersal is the only possible explanation and plate tectonic explanations are not viable. Other families with a crown age appropriate to be explained by plate tectonics did not seem to have distributions indicating an involvement of long-distance dispersal, but the advent of molecular systematics and molecular clocks has shown this to be otherwise. Families exhibiting this pattern include Fabaceae and Lauraceae (and many others), and in spite of the unlikely dispersal qualities of their generally large seeds, they exhibit many instances of long-distance dispersal occurring throughout their evolutionary history; in fact, long-distance dispersal is the most probable explanation to account for the current distributions of the great majority of land plant families. One factor that sometimes is overlooked is the boreotropics hypothesis, which may explain more recent connections between American, African and Asian floristic components. However, in some old lineages with small propagules that appear well adapted to long-distance dispersal, such as Marattiaceae and Orchidaceae, we find a pattern suggesting that tectonics is the primary factor, with clades clearly restricted to one tropical region. These patterns appear to have little to do with dispersability and it is probable that their conforming to expected (tectonic) biogeographical patterns has to do with their specialized life-history strategies that have acted to make intercontinental establishment unlikely even though dispersal almost certainly occurs. Molecular studies have identified additional, unanticipated clades, and these fit into the relictual category with what may be an overlay of old long-distance dispersal events. Examples at the ordinal level are Crossosomatales and Huerteales, and we expect future studies to identify more of these relict and unexpected clades at many taxonomic levels. Overall, molecular systematic studies and molecular clocks have demonstrated that there are many more connections between the Neotropics and Palaeotropics, both Asia and Africa, than previously would have been thought under a plate tectonic model. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012,●●, ●●-●●. [ABSTRACT FROM AUTHOR]