Molecular phylogeny and divergence time of Harpalyce (Leguminosae, Papilionoideae), a lineage with amphitropical diversification in seasonally dry forests and savannas.

Our knowledge of the systematics of the papilionoid legume tribe Brongniartieae has greatly benefitted from recent advances in molecular phylogenetics. The tribe was initially described to include species marked by a strongly bilabiate calyx and an embryo with a straight radicle, but recent research has placed taxa from the distantly related core Sophoreae and Millettieae within it. Despite these advances, the most species-rich genera within the Brongniartieae are still not well studied, and their morphological and biogeographical evolution remains poorly understood. Comprising 35 species, Harpalyce is one of these poorly studied genera. In this study, we present a comprehensive, multi-locus molecular phylogeny of the Brongniartieae, with an increased sampling of Harpalyce, to investigate morphological and biogeographical evolution within the group. Our results confirm the monophyly of Harpalyce and indicate that peltate glandular trichomes and a strongly bilabiate calyx with a carinal lip and three fused lobes are synapomorphies for the genus, which is internally divided into three distinct ecologically and geographically divergent lineages, corresponding to the previously recognized sections. Our biogeographical reconstructions demonstrate that Brongniartieae originated in South America during the Eocene, with subsequent pulses of diversification in South America, Mesoamerica, and Australia. Harpalyce also originated in South America during the Miocene at around 20 Ma, with almost synchronous later diversification in South America and Mexico/Mesoamerica beginning 10 Ma, but mostly during the Pliocene. Migration of Harpalyce from South to North America was accompanied by a biome and ecological shift from savanna to seasonally dry forest.

Underlying and proximate drivers of biodiversity changes in Mesoamerican biosphere reserves.

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas' effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a "winner and loser" species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.

Biogeographic regionalization by spatial and environmental components: Numerical proposal.

Regionalization through the analysis of species groups offers important advantages in conservation biology, compared to the single taxon approach in areas of high species richness. We use a systematic framework for biogeographic regionalization at a regional scale based on species turnover and environmental drivers (climate variables and soil properties) mainly of herbaceous plant species richness. To identify phytogeographic regions in the Balsas Depression (BD), we use Asteraceae species, a family widely distributed in Seasonally Dry Tropical Forest (SDTF) and the most diverse of the vascular plants in Mexico. Occurrence records of 571 species were used to apply a quantitative analysis based on the species turnover, the rate of changes in their composition between sites (ß-Simpson index) and the analysis of the identified environmental drivers. Also, the environmental predictors that influence species richness in the SDTF were determined with a redundancy analysis. We identified and named two phytogeographic districts within the SDTF of the BD (Upper Balsas and Lower Balsas). According to the multi-response permutation procedure, floristic composition of the two districts differs significantly, and the richness of exclusive species in Upper Balsas was higher (292 species) than in the Lower Balsas (32 species). The proportion of Mg and Ca in the soil and the precipitation of the driest three-month period were the environmental factors with greatest positive influence on species richness. The division of geographic districts subordinated to the province level, based on diverse families such as Asteraceae, proved to be appropriate to set up strategies for the conservation of the regional flora, since at this scale, variation in species richness is more evident. Our findings are consistent with a growing body of biogeographic literature that indicates that the identification of smaller biotic districts is more efficient for the conservation of biodiversity, particularly of endemic or rare plants, whose distribution responds more to microhabitats variation.

A molecular phylogeny reveals the Cuban enigmatic genus Behaimia as a new piece in the Brongniartieae puzzle of papilionoid legumes.

The papilionoid legume tribe Brongniartieae comprises a collection of 15 genera with disparate morphologies that were previously positioned in at least four remotely related tribes. The Brongniartieae displays a wide geographical disjunction between Australia and the New World and previous phylogenetic studies had provided conflicting results about the relationships between the American and Australian genera. We carry out phylogenetic analyses of (1) a plastid matK dataset extensively sampled across legumes to solve the enigmatic relationship of the Cuban-endemic monospecific genus Behaimia; and (2) multilocus datasets with focus on all genera ever referred to Brongniartieae. These analyses resulted in a well-resolved and strongly-supported phylogenetic tree of the Brongniartieae. The monophyly of all American genera of Brongniartieae is strongly supported. The doubtful position of the Australian genus Plagiocarpus is resolved within a clade comprising all Australian genera. Behaimia has been traditionally classified in tribe Millettieae, but our new molecular data and re-assessment of morphological traits have resolved the genus within the early-branching papilionoid tribe Brongniartieae. Characters including the pinnately multifoliolate (vs. unifoliolate) leaves, a sessile (vs. stipitate) ovary, and an indehiscent or late dehiscent one-seeded pod distinguish Behaimia from its closer relatives, the South American genera Cyclolobium and Limadendron.

Genetic diversity and structure of wild populations of the tropical dry forest tree Jacaratia mexicana (Brassicales: Caricaceae) at a local scale in Mexico.

The tropical dry forest is a greatly endangered ecosystem, from which Jacaratia mexicana is a native tree. With the aim to assess the levels of genetic variation and population structure, four wild populations of J. mexicana were studied in the Sierra de Huautla Biosphere Reserve, Morelos, Mexico. For this, DNA was extracted from 159 individuals and were amplified with six random primers using the Random Amplified Polymorphic DNA (RAPD). A total of 54 bands were obtained, of which 50 (92.6%) were polymorphic. The total genetic diversity found within the four populations was 0.451 when estimated by Shannon's index. An AMOVA analysis showed that 84% of the total genetic variation was found within populations and 16% was among populations. The UPGMA dendrogram showed that all individuals from one of the populations (Huaxtla) formed one distinct genetic group, while the rest of the individuals did not cluster according to population. A Mantel test did not show an association between genetic and geographical distances among populations (r=0.893, p=0.20). A Bayesian cluster analysis performed with STRUCTURE, showed that the most probable number of genetic groups in the data was four (K=4), and confirmed the distinctness of Huaxtla population. Our results showed that important genetic differentiation among populations can occur even at this small geographic scale and this has to be considered in conservation actions for this genetic resource.

Genetic diversity and structure of wild populations of the tropical dry forest tree Jacaratia Mexicana (Brassicales: Caricaceae) at a local scale in Mexico

The tropical dry forest is a greatly endangered ecosystem, from which Jacaratia mexicana is a native tree. With the aim to assess the levels of genetic variation and population structure, four wild populations of J. mexicana were studied in the Sierra de Huautla Biosphere Reserve, Morelos, Mexico. For this, DNA was extracted from 159 individuals and were amplified with six random primers using the Random Amplified Polymorphic DNA (RAPD). A total of 54 bands were obtained, of which 50 (92.6%) were polymorphic. The total genetic diversity found within the four populations was 0.451 when estimated by Shannon’s index. An AMOVA analysis showed that 84% of the total genetic variation was found within populations and 16% was among populations. The UPGMA dendrogram showed that all individuals from one of the populations (Huaxtla) formed one distinct genetic group, while the rest of the individuals did not cluster according to population. A Mantel test did not show an association between genetic and geographical distances among populations (r=0.893, p=0.20). A Bayesian cluster analysis performed with STRUCTURE, showed that the most probable number of genetic groups in the data was four (K=4), and confirmed the distinctness of Huaxtla population. Our results showed that important genetic differentiation among populations can occur even at this small geographic scale and this has to be considered in conservation actions for this genetic resource.

Jacaratia mexicana es un árbol nativo del bosque tropical seco, que es considerado el tipo de vegetación en mayor riesgo de desaparecer completamente. Se utilizaron polimorfismos de ADN amplificados al azar (RAPD, Random Amplified Polymorphic DNA), para evaluar los niveles de variación y estructura genética en cuatro poblaciones silvestres de J. mexicana en la Reserva de la Biósfera Sierra de Huautla (Morelos, México). Se amplificó el ADN de 159 individuos utilizando seis oligonucleótidos (“primers”) aleatorios. Se obtuvieron en total 54 bandas, de las cuales 50 (92.6%) fueron polimórficas. La diversidad genética total que se encontró en las cuatro poblaciones de J. mexicana fue de 0.451 de acuerdo con el índice de Shannon. Un análisis de varianza molecular (AMOVA) mostró que el 84% de la variación genética total se encuentra dentro de las poblaciones y el 16% entre las poblaciones. Un dendrograma construido mediante el algoritmo UPGMA mostró que los individuos de una población (Huaxtla) formaron un grupo, mientras que el resto de los individuos no se agruparon de acuerdo a su población de origen. Una prueba de Mantel no mostró una asociación entre las distancias genéticas y geográficas entre las poblaciones (r=0.893, p=0.20). Un análisis de agrupamiento Bayesiano realizado mediante STRUCTURE mostró que el número más probable de grupos genéticos es cuatro (K=4) y confirmó la diferenciación de la población Huaxtla. Nuestros resultados muestran que una considerable diferenciación genética entre poblaciones puede existir incluso a esta escala geográfica, lo cual es de interés para la conservación de este recurso genético.

Dermatitis perioral por anticonceptivos orales: presentación de 1 caso / Perioral dermatitis due to oral contraceptives: a case report

Se presentó el caso de una mujer de 20 años de edad que padecía lesiones de dermatitis perioral de varios meses de evolución y había utilizado una variada gama de medicamentos tópicos sin mejoría. Se comprobó, por prueba de parche, la sensibilización a medicamentos anticonceptivos orales que utilizaba diariamente desde igual período de aparición del cuadro dermatológico. Se corroboró el diagnóstico por estudio anatomopatológico de la biopsia de piel

Dermatitis perioral por anticonceptivos orales: presentación de 1 caso / Perioral dermatitis due to oral contraceptives: a case report

Se presentó el caso de una mujer de 20 años de edad que padecía lesiones de dermatitis perioral de varios meses de evolución y había utilizado una variada gama de medicamentos tópicos sin mejoría. Se comprobó, por prueba de parche, la sensibilización a medicamentos anticonceptivos orales que utilizaba diariamente desde igual período de aparición del cuadro dermatológico. Se corroboró el diagnóstico por estudio anatomopatológico de la biopsia de piel(AU)