Advances in Legume Systematics 14. Classification of Caesalpinioideae. Part 2: Higher-level classification.

Caesalpinioideae is the second largest subfamily of legumes (Leguminosae) with ca. 4680 species and 163 genera. It is an ecologically and economically important group formed of mostly woody perennials that range from large canopy emergent trees to functionally herbaceous geoxyles, lianas and shrubs, and which has a global distribution, occurring on every continent except Antarctica. Following the recent re-circumscription of 15 Caesalpinioideae genera as presented in Advances in Legume Systematics 14, Part 1, and using as a basis a phylogenomic analysis of 997 nuclear gene sequences for 420 species and all but five of the genera currently recognised in the subfamily, we present a new higher-level classification for the subfamily. The new classification of Caesalpinioideae comprises eleven tribes, all of which are either new, reinstated or re-circumscribed at this rank: Caesalpinieae Rchb. (27 genera / ca. 223 species), Campsiandreae LPWG (2 / 5-22), Cassieae Bronn (7 / 695), Ceratonieae Rchb. (4 / 6), Dimorphandreae Benth. (4 / 35), Erythrophleeae LPWG (2 /13), Gleditsieae Nakai (3 / 20), Mimoseae Bronn (100 / ca. 3510), Pterogyneae LPWG (1 / 1), Schizolobieae Nakai (8 / 42-43), Sclerolobieae Benth. & Hook. f. (5 / ca. 113). Although many of these lineages have been recognised and named in the past, either as tribes or informal generic groups, their circumscriptions have varied widely and changed over the past decades, such that all the tribes described here differ in generic membership from those previously recognised. Importantly, the approximately 3500 species and 100 genera of the former subfamily Mimosoideae are now placed in the reinstated, but newly circumscribed, tribe Mimoseae. Because of the large size and ecological importance of the tribe, we also provide a clade-based classification system for Mimoseae that includes 17 named lower-level clades. Fourteen of the 100 Mimoseae genera remain unplaced in these lower-level clades: eight are resolved in two grades and six are phylogenetically isolated monogeneric lineages. In addition to the new classification, we provide a key to genera, morphological descriptions and notes for all 163 genera, all tribes, and all named clades. The diversity of growth forms, foliage, flowers and fruits are illustrated for all genera, and for each genus we also provide a distribution map, based on quality-controlled herbarium specimen localities. A glossary for specialised terms used in legume morphology is provided. This new phylogenetically based classification of Caesalpinioideae provides a solid system for communication and a framework for downstream analyses of biogeography, trait evolution and diversification, as well as for taxonomic revision of still understudied genera.

To converge or not to converge in environmental space: testing for similar environments between analogous succulent plants of North America and Africa.

BACKGROUND AND AIMS: Convergent evolution is invoked to explain similarity between unrelated organisms in similar environments, but most evaluations of convergence analyse similarity of organismal attributes rather than of the environment. This study focuses on the globular succulent plants of the Americas, the cacti, and their counterparts in Africa in the ice-plant, spurge and milkweed families. Though often held up as paragons of convergent morphological evolution, the environmental similarity of these plants has remained largely unexamined from a quantitative perspective. METHODS: Five hotspots (centres of high species diversity of globular succulents) were selected, two in Mexico and three in South Africa. Their environments were compared using niche modelling tools, randomization tests of niche similarity and multivariate analyses to test for environmental similarity. KEY RESULTS: Although the sites selected have 'similar' but unrelated life forms, almost all our results highlighted more climate differences than similarities between the hotspots. Interprediction of niches within and between continents, a niche equivalence test, and MANOVA results showed significant differences. In contrast, a niche similarity test showed that the comparisons of Cuatrociénegas-Richtersveld, Huizache-Knersvlakte and Huizache-Richtersveld were similar. CONCLUSIONS: Differences in rainfall and temperature regimes and the potential effect of edaphic factors may be involved in the differences between the hotspots. In addition, differences in structure, morphology and physiology of the globular succulents may coincide with some of the climatic dissimilarities; i.e. given convergence as the evolution of similar morphologies under similar conditions, then it may be that differing environments diagnose inconspicuous morphological differences. Moreover, although fine-scale differences between sites were found, a coarser perspective shows that these sites are clearly similar as drylands with relatively moderate drought and mild temperatures, illustrating how all studies of convergence must address the issue of how similar two entities must be before they are considered convergent.

Phylogenetic relationships and evolution of growth form in Cactaceae (Caryophyllales, Eudicotyledoneae).

PREMISE OF THE STUDY: Cactaceae is one of the most charismatic plant families because of the extreme succulence and outstanding diversity of growth forms of its members. Although cacti are conspicuous elements of arid ecosystems in the New World and are model systems for ecological and anatomical studies, the high morphological convergence and scarcity of phenotypic synapomorphies make the evolutionary relationships and trends among lineages difficult to understand. METHODS: We performed phylogenetic analyses implementing parsimony ratchet and likelihood methods, using a concatenated matrix with 6148 bp of plastid and nuclear markers (trnK/matK, matK, trnL-trnF, rpl16, and ppc). We included 224 species representing approximately 85% of the family's genera. Likelihood methods were used to perform an ancestral character reconstruction within Cactoideae, the richest subfamily in terms of morphological diversity and species number, to evaluate possible growth form evolutionary trends. KEY RESULTS: Our phylogenetic results support previous studies showing the paraphyly of subfamily Pereskioideae and the monophyly of subfamilies Opuntioideae and Cactoideae. After the early divergence of Blossfeldia, Cactoideae splits into two clades: Cacteae, including North American globose and barrel-shaped members, and core Cactoideae, including the largest diversity of growth forms distributed throughout the American continent. Para- or polyphyly is persistent in different parts of the phylogeny. Main Cactoideae clades were found to have different ancestral growth forms, and convergence toward globose, arborescent, or columnar forms occurred in different lineages. CONCLUSIONS: Our study enabled us to provide a detailed hypothesis of relationships among cacti lineages and represents the most complete general phylogenetic framework available to understand evolutionary trends within Cactaceae.

Burden of influenza-associated respiratory hospitalizations in the Americas, 2010-2015.

BACKGROUND: Despite having influenza vaccination policies and programs, countries in the Americas underutilize seasonal influenza vaccine, in part because of insufficient evidence about severe influenza burden. We aimed to estimate the annual burden of influenza-associated respiratory hospitalizations in the Americas. METHODS: Thirty-five countries in the Americas with national influenza surveillance were invited to provide monthly laboratory data and hospital discharges for respiratory illness (International Classification of Diseases 10th edition J codes 0-99) during 2010-2015. In three age-strata (<5, 5-64, and ≥65 years), we estimated the influenza-associated hospitalizations rate by multiplying the monthly number of respiratory hospitalizations by the monthly proportion of influenza-positive samples and dividing by the census population. We used random effects meta-analyses to pool age-group specific rates and extrapolated to countries that did not contribute data, using pooled rates stratified by age group and country characteristics found to be associated with rates. RESULTS: Sixteen of 35 countries (46%) contributed primary data to the analyses, representing 79% of the America's population. The average pooled rate of influenza-associated respiratory hospitalization was 90/100,000 population (95% confidence interval 61-132) among children aged <5 years, 21/100,000 population (13-32) among persons aged 5-64 years, and 141/100,000 population (95-211) among persons aged ≥65 years. We estimated the average annual number of influenza-associated respiratory hospitalizations in the Americas to be 772,000 (95% credible interval 716,000-829,000). CONCLUSIONS: Influenza-associated respiratory hospitalizations impose a heavy burden on health systems in the Americas. Countries in the Americas should use this information to justify investments in seasonal influenza vaccination-especially among young children and the elderly.

High proportion of cactus species threatened with extinction.

A high proportion of plant species is predicted to be threatened with extinction in the near future. However, the threat status of only a small number has been evaluated compared with key animal groups, rendering the magnitude and nature of the risks plants face unclear. Here we report the results of a global species assessment for the largest plant taxon evaluated to date under the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, the iconic Cactaceae (cacti). We show that cacti are among the most threatened taxonomic groups assessed to date, with 31% of the 1,478 evaluated species threatened, demonstrating the high anthropogenic pressures on biodiversity in arid lands. The distribution of threatened species and the predominant threatening processes and drivers are different to those described for other taxa. The most significant threat processes comprise land conversion to agriculture and aquaculture, collection as biological resources, and residential and commercial development. The dominant drivers of extinction risk are the unscrupulous collection of live plants and seeds for horticultural trade and private ornamental collections, smallholder livestock ranching and smallholder annual agriculture. Our findings demonstrate that global species assessments are readily achievable for major groups of plants with relatively moderate resources, and highlight different conservation priorities and actions to those derived from species assessments of key animal groups.

Endangered Cacti in the Chihuahuan Desert: I. Distribution Patterns.

We mapped the geographical distributions of 93 endangered species of cacti from the Chihuahuan Desert Region. We divided the region into grids of 30 minutes latitude by 30 minutes longitude and calculated species frequencies for each grid. The grids with the highest species richness values are aggregated in areas of moderate elevation, particularly towards the southeastern and to a lesser extent, the eastern margins of the Chihuahuan Desert Region, in northern San Luis Potosi and the southern portions of Coahuila, Nuevo Leén, and Tamaulipas. This vast area constitutes the most important nucleus of cactus species concentration in the continent. Species richness decreases toward the western segment of the Chihuahuan Desert Region and from the Cuatro Ciénegas region to the north and northwest. Another important area is the Queretaroan-Hidalgoan Arid Zone, where several grids containing an important assemblage of endangered species occur. Climatic factors, such as minimum temperatures and mean annual precipitation, explain the current distribution patterns of these plants, and the recent Pleistocene climatic episodes appear to have played a determinant role in the existence of areas of high species concentration and in the proliferation of narrow endemics. Special actions are urgently needed to conserve the endangered Cactaceae of this region. We propose that a carefully selected network of small areas would be an appropriate approach for the conservation of these plants. But species richness cannot be taken as the sole criterion in the determination of protected areas. Additional criteria, such as degree of endemicity, degree of threat to species and areas, habitat diversity, and biogeographic congruence with other plant and animal groups, should be analyzed before these areas are selected. Propagation in botanical gardens using scientific criteria and commercial propagation would be additional methods of conservation. Cactáceas Amenazadas en el Desierto Chihuahuense: I. Patrones de Distribución.

Resumen: Se integraron las distribuciones geográficas de 93 especies de cactáceas amenzadas de la Región del Desierto Chihuahuense. Esta región se subdividió en cuadros de 30 minutos de latitud por 30 minutos de longitud y se calcularon las frecuencias de especies para cada uno de los cuadros. Los cuadros con los mayores valores de riqueza de especies están agregados en áreas de altitud moderada, ubicados particularmente hacia los márgenes sureste, y en menor medida, este de la Región del Desierto Chihuahuense, en el norte de San Luis Potosí, y en el sur de Coahuila, Nuevo León y Tamaulipas. Esta vasta área constituye el núcleo de concentración de especies de cactáceas amenazadas más importante del continente. A partir de esta área, la riqueza de especies decrece hacia el segmento oeste de la Región del Desierto Chihuahuense y de la región de Cuatro Ciénegas hacia el norte y noroeste. Además, en la Zona Arida Queretano-Hidalguense, la cual es considerada como una disyunción del Desierto Chihuahuense, se localizan varios cuadros con un importante contingente de especies amenazadas. Algunos factores climáticos, tales como temperaturas mínimas y precipitación promedio anual, explican los patrones de distribución actuales de estas plantas, y los eventos climáticos del Pleistoceno parecen haber jugado un papel determinante en la existencia de áreas de alta concentración de especies y en la proliferación de endemismos restringidos. Se requieren acciones especiales para protegar a las cactáceas amenazadas de la Región del Desierto Chihuahuense. Se propone que un enfoque apropiado para la conservación de estas plantas podria ser la selección cuidadosa de una red de pequeñas áreas. Sin embargo, la riqueza de especies no es el único criterio en la determinación de áreas protegidas. Existen criterios adicionales tales como la frecuencia de endemismos, el grado de amenaza de áreas y especies en particular, la diviersidad de hábitats y la congruencia biogeográfica con otros grupos de plantas y antimales, los que deberán ser analizados antes de que estas áreas sean seleccionadas. La propagación en jardines botánicos con criterios científicos, así como la propagación comercial, podrían ser métodos adicionales de conservación.

DNA barcodes for Mexican Cactaceae, plants under pressure from wild collecting.

DNA barcodes could be a useful tool for plant conservation. Of particular importance is the ability to identify unknown plant material, such as from customs seizures of illegally collected specimens. Mexican cacti are an example of a threatened group, under pressure because of wild collection for the xeriscaping trade and private collectors. Mexican cacti also provide a taxonomically and geographically coherent group with which to test DNA barcodes. Here, we sample the matK barcode for 528 species of Cactaceae including approximately 75% of Mexican species and test the utility of the matK region for species-level identification. We find that the matK DNA barcode can be used to identify uniquely 77% of species sampled, and 79-87% of species of particular conservation importance. However, this is far below the desired rate of 95% and there are significant issues for PCR amplification because of the variability of primer sites. Additionally, we test the nuclear ITS regions for the cactus subfamily Opuntioideae and for the genus Ariocarpus (subfamily Cactoideae). We observed higher rates of variation for ITS (86% unique for Opuntioideae sampled) but a much lower PCR success, encountering significant intra-individual polymorphism in Ariocarpus precluding the use of this marker in this taxon. We conclude that the matK region should provide useful information as a DNA barcode for Cactaceae if the problems with primers can be addressed, but matK alone is not sufficiently variable to achieve species-level identification. Additional complementary regions should be investigated as ITS is shown to be unsuitable.

Characterization of microsatellite loci for the critically endangered cactus Ariocarpus bravoanus.

Ariocarpus bravoanus is common in trade but critically endangered in its natural habitat. With the ultimate aim of developing a certification scheme to aid in the conservation of this species, we have isolated A. bravoanus microsatellites from a nonenriched library. Fifty-four sequences contained a microsatellite array, of which eight were polymorphic among 23 individuals, 20 from one population and three plants from trade.

Measuring scientists’ performance: a view from organismal biologist / Midiendo el desempeño de los científicos: un punto de vista de biólogos organísmicos / Medindo desempeenho dos cientistas: um ponto de vista de biólogos organísmioss

Increasingly, academic evaluations quantify performance in science by giving higher rank to scientists (as well as journals and institutions) who publish more articles and have more citations. In Mexico, for example, a centralized federal agency uses such bibliometric statistics for evaluating the performance of all Mexican scientists. In this article we caution against using this form of evaluation as an almost exclusive tool of measuring and comparing scientists’ performance. We argue that from an economic viewpoint, maximizing the number of journal articles and their citations does not necessarily correspond to the preferences and needs of society. The traditional peer review process is much better suited for that purpose, and we propose "rule-based peer review" for evaluating a large number of scientists.

En la ciencia hay una fuerte tendencia global de cuantificar el desempeño de los científicos (así como a las revistas e instituciones), dando mayor jerarquía a aquellos científicos que publican más artículos y son más citados. En México, por ejemplo, una institución federal centralizada usa tales estadísticas bibliométricas para evaluar el desempeño de todos los científicos del país. En este artículo advertimos sobre los inconvenientes de esta forma de evaluación como una herramienta casi única para medir y comparar el desempeño de los científicos. Argumentamos que, desde un punto de vista económico, la maximización del número de artículos científicos y de la frecuencia de sus citas no necesariamente corresponde a las preferencias y necesidades de la sociedad en general. El proceso tradicional de arbitraje por pares es más adecuado para este propósito, y proponemos el "arbitraje por pares basado en reglas" para evaluar a un número alto de científicos.

Há uma forte tendência global para avaliações acadêmicas que quantifiquem o desempenho nas ciências através de ranquear os cientistas (assim como revistas e instituições) que publicam mais artigos e têm mais citações. No México, por exemplo, um órgão centralizado do governo utiliza tais estatísticas bibliomêtricas para avaliar o desempenho de todos os cientistas mexicanos. No presente artigo, chamamos atenção ao uso desta forma de avaliação como ferramenta quase que exclusiva para medir e comparar o desempenho dos cientistas. Argumentamos de um ponto de vista econômico que maximizar o número de artigos e as suas citações não corresponde necessariamente às preferências e necessidades da sociedade. O processo tradicional de avaliação pelos pares é mais apropriado para esta finalidade, e propomos um sistema baseado em "avaliação pelos pares seguindo regras", que podem avaliar um grande numéro de cientistas.