21 research outputs found
Sistemática del género Bdallophytum (Cytinaceae)
The genus Bdallophytum is comprised of root parasitic plants distributed in northern neotropics. In Mexico occur all the species of the genus, two of which are endemic. The genus has previously been positioned within the tribe Cytineae of the Rafflesiaceae, but based on results from molecular phylogenetic analyses, this tribe is currently recognized at the rank of family as Cytinaceae. Historically, one to four species have been accepted in the genus, and the most-recent taxonomic treatment for the genus was realized more than 70 years ago. In the present work, a principal coordinate analysis was conducted in order to evaluate the identity and number of species in this genus. The results of this analysis suggest the recognition of three species. A taxonomic study with a key to species is presented, along with bibliographic information, morphological descriptions, specimens examined, ecological information, distributional maps and photos of the species.El género Bdallophytum está integrado por plantas parásitas de raÃces y restringe su distribución a la parte septentrional del neotrópico. En México se presentan todas sus especies, dos de las cuales son endémicas. Anteriormente se le ubicaba en la tribu Cytineae de la familia Rafflesiaceae, pero según los estudios filogenéticos basados en datos moleculares, este grupo se reconoce ahora a nivel de familia como Cytinaceae. En su historia se han reconocido para Bdallophytum de uno a cuatro componentes y la última revisión taxonómica para el género fue realizada hace más de 70 años. El presente trabajo se apoya en un análisis de coordenadas principales para evaluar la identidad y número de miembros que lo integran, reconociéndose tres especies. Se proporciona una clave de su identificación, asà como datos bibliográficos, descripciones morfológicas, enumeración de los ejemplares estudiados, información ecológica, mapas de distribución y fotografÃas
Odontadenia macrantha (Apocynaceae; Apocynoideae): distribución y nuevos registros en México
Background and Objectives: Apocynaceae are one of the most species diverse groups of Mexico with numerous contributions to understand its systematics and distribution. However, some taxa are little known, as in the case of Odontadenia macrantha. A description, new distribution records, and conservation status of O. macrantha in Mexico are presented.Methods: Based on detailed observation of specimens from different herbaria and taxonomic literature, a description of the taxon and a key to morphologically and geographically close species is presented. In addition, an assessment of the conservation status of the species in Mexico, based on the IUCN criteria, and a distribution map are provided.Key results: The presence of this species in Tabasco and Veracruz extends its distribution further northwards. Additionally, these records provided new types of vegetation in which the species grows, such as tropical rain forest, tropical forest with Curatella, tropical deciduous forest and Quercus forest. Odontadenia macrantha is a taxon of variable morphology, which is corroborated here, because it has smaller corollas than the individuals of southern populations. Here is suggested to place this species in the category of Endangered (EN C2ai) for being restricted to a small tropical area with a high anthropogenic activity and few individuals in the observed populations.Conclusions: These new records suggest that the constant review of biological collections to maintain knowledge on taxa updated is needed. In addition, collection activities should be continued in the vegetation remnants of Tabasco and Veracruz.Antecedentes y Objetivos: Las Apocynaceae son uno de los grupos más diversos de México con numerosos aportes para entender su sistemática y distribución. No obstante, algunos taxones son poco conocidos, como es el caso de Odontadenia macrantha. Se presentan una descripción, nuevos registros de distribución y el estado de conservación de O. macrantha en México.Métodos: Con base en la observación detallada de especÃmenes de diferentes herbarios y la revisión de bibliografÃa taxonómica, se presenta una descripción del taxon y una clave de especies morfológicamente y geográficamente cercanas. Además, se proporciona una evaluación sobre el estado de conservación de la especie en México, de acuerdo a los criterios de la UICN, y un mapa de distribución.Resultados clave: La presencia de esta especie en Tabasco y Veracruz extiende su distribución a una zona más norteña. Además estos registros ofrecen nuevos tipos de vegetación en los cuales se encuentra la especie, como el bosque tropical perennifolio, bosque tropical con Curatella, bosque tropical caducifolio y bosque de Quercus. Odontadenia macrantha es un taxon de morfologÃa variable, lo cual se corrobora aquÃ, ya que presenta corolas más pequeñas que los individuos de poblaciones sureñas. Se sugiere ubicar esta especie en la categorÃa de En Peligro (EN C2ai) por estar restringida a una pequeña zona tropical con alta actividad antropogénica y pocos individuos en las poblaciones observadas.Conclusiones: Estos nuevos registros sugieren que es necesaria la constante revisión de las colecciones biológicas para mantener actualizado el conocimiento de los taxones. Además, debe continuarse el trabajo de recolecta en los remanentes de vegetación de Tabasco y Veracruz
Synopsis of the genus Spigelia (Loganiaceae) in North America, Central America, and the Caribbean
Antecedentes y Objetivos: Spigelia es un género neotropical con cerca de 90 especies distribuidas desde los Estados Unidos de América hasta Argentina. La diversidad del género presenta una separación espacial entre un grupo en Norte-Centroamérica/Caribe (NA) y otro en Sudamérica (SA), cada uno con un importante centro de diversificación. Sin embargo, el conocimiento sistemático del grupo no ha sido actualizado en los últimos 10 años, por lo que el objetivo de este trabajo es generar una sinopsis sistemática para el género distribuido en la región NA.
Métodos: El trabajo se realizó a través de la búsqueda de información bibliográfica para obtener la historia taxonómica, asà como trabajo de campo y revisión de material herborizado, a partir del cual se realizaron descripciones diagnósticas y mapas de distribución.
Resultados clave: Se encontraron 29 especies distribuidas en la región NA, lo que representa alrededor de 30% de la diversidad del género, en las zonas tropical y subtropical. En la región NA, Mesoamérica es una de las regiones en las que se concentra la diversidad vegetal, lo que la cataloga como hotspot. El trabajo incluye información novedosa sobre la morfologÃa del grupo, como descripciones de los caracteres polÃnicos y carpológicos, claves de identificación por regiones en NA y mapas de distribución en el área de estudio.
Conclusiones: Este estudio representa el primer tratamiento taxonómico para el género Spigelia que incluye todas las especies de la región central y norte del continente americano. La información recopilada en este trabajo puede ser útil para ser integrada en análisis filogenéticos que ayuden a resolver las relaciones intragenéricas del grupo. Asimismo, la aplicación de herramientas de modelado de distribución potencial que permitan ubicar áreas para futuras colectas, asà como el desarrollo de análisis biogeográficos que ayuden a comprender la distribución de la diversidad de Spigelia a lo largo del continente.Background and Aims: Spigelia is a Neotropical genus with about 90 species distributed from the United States of America to Argentina. The diversity of the genus presents a spatial separation with a group in North-Central America/ the Caribbean (NA) and another in South America (SA), each with an important center of diversification. However, the systematic knowledge of the group has not been updated in the last 10 years, so the objective of this work is to generate a systematic synopsis for the genus distributed in the NA region.
Methods: The work was carried out through the search for bibliographic information to obtain the taxonomic history, field work and review of herbarium material, based on which diagnostic descriptions and distribution maps were made.
Key results: Twenty-nine species distributed in the NA region were found, which represents about 30% of the diversity of the genus, distributed in the tropical and subtropical zones. In the NA region, Mesoamerica is one of the regions in which plant diversity is concentrated, which classifies it as a hotspot. This work includes novel information on the morphology of the group, such as descriptions of the pollen and carpological characters, identification keys for regions in NA and distribution maps in the study area.
Conclusions: This study represents the first taxonomic treatment for the genus Spigelia that includes all the species of the central and northern regions of the Americas. The information collected in this work may be useful to be integrated into phylogenetic analyzes that help resolve the infrageneric relationships of the group. Likewise, the application of potential distribution modeling tools that would allow locating areas for future collection, as well as the development of biogeographic analyzes that help us understand the distribution patterns of Spigelia diversity along the continent
Gonolobus gonzaleziarum (Apocynaceae), especie nueva de la ecorregión Madrense Tropical de la Sierra Madre Occidental, México
Background and Aims: Gonolobus comprises around 150 species in the world, with just over 40 of them distributed in Mexico. In the last two years, at least five new species have been described for this country. This paper describes a new species within the subgenus Pseudolachnostoma.Methods: Thirteen herbaria, three digital databases, and specialized literature were revised. Based on this, similar species were compared, and an identification key was generated. Field expeditions were made from 2019 to 2022 to gather botanical collections and monitor the phenology of the species of interest. The cohesive species concept was proposed as an explanatory hypothesis for the recognition of the taxa discussed here. Key results: The new species, Gonolobus gonzaleriarum, is described and located in two forests of Pinus-Quercus between the southeastern and southwestern limits of the states of Sinaloa and Durango, respectively. It differs from the species of the subgenus Pseudolachnostoma by having a gynostegium with a reduced stipe, lobes of the corolla and sepals of shorter length than the tube, citrus aroma, and a dense inflorescence. We included photographic plates, and an illustration with the distinctive characters, as well as a dichotomous key for the species of the subgenus Pseudolachnostoma. Based on its reduced range and impacted habitat, it is considered a threatened species, according to IUCN criteria.
Conclusions: With the present discovery, the genus Gonolobus reaches 45 species in Mexico with 24 endemics. Gonolobus gonzaleriarum has great ornamental potential considering its conspicuous inflorescences and pleasant citrus aroma, which could encourage strategies for its conservation, since it is found in a restricted distribution and threatened habitat.Antecedentes y Objetivos: Gonolobus comprende alrededor de 150 especies en el mundo, con poco más de 40 de ellas distribuidas en México. En los últimos dos años se han descrito al menos cinco nuevas especies de este paÃs. En el presente trabajo se describe una nueva especie dentro del subgénero Pseudolachnostoma.
Métodos: Se revisaron 13 herbarios, tres bases de datos digitales y literatura especializada. Con base en esto se compararon las especies similares y se generó una clave de identificación. Se realizaron expediciones a campo de 2019 a 2022 y se colectó y monitoreó la fenologÃa de la especie de interés. Se planteó como hipótesis explicativa el concepto cohesivo de especie para el reconocimiento de los taxones aquàtratados. Resultados clave: Se describe la especie nueva Gonolobus gonzaleriarum, conocida de dos localidades de bosques de Pinus-Quercus entre los lÃmites sureste y suroeste de los estados de Sinaloa y Durango, respectivamente. Se diferencia de las especies del subgénero Pseudolachnostoma por poseer ginostegio con un estÃpite reducido, lóbulos de la corola y sépalos de menor longitud que el tubo, aroma cÃtrico e inflorescencia densa. Se incluyen láminas fotográficas y una ilustración con los caracteres distintivos de la nueva especie, asà como una clave dicotómica con las especies del subgénero Pseudolachnostoma. Con base en su área de distribución reducida y hábitat impactado, se considera una especie amenazada de acuerdo con los criterios de la IUCN.Conclusiones: Con el presente descubrimiento, el género Gonolobus llega a 45 especies en México con 24 endémicas. Gonolobus gonzaleriarum se considera con gran potencial ornamental por sus inflorescencias conspicuas y agradable aroma cÃtrico, lo que motiva en fomentar estrategias para su conservación, ya que se encuentra en una distribución restringida y hábitat amenazado
The diversity and evolution of pollination systems in large plant clades: Apocynaceae as a case study
Large clades of angiosperms are often characterized by diverse interactions with pollinators, but how these pollination systems are structured phylogenetically and biogeographically is still uncertain for most families. Apocynaceae is a clade of >5300 species with a worldwide distribution. A database representing >10 % of species in the family was used to explore the diversity of pollinators and evolutionary shifts in pollination systems across major clades and regions.The database was compiled from published and unpublished reports. Plants were categorized into broad pollination systems and then subdivided to include bimodal systems. These were mapped against the five major divisions of the family, and against the smaller clades. Finally, pollination systems were mapped onto a phylogenetic reconstruction that included those species for which sequence data are available, and transition rates between pollination systems were calculated.Most Apocynaceae are insect pollinated with few records of bird pollination. Almost three-quarters of species are pollinated by a single higher taxon (e.g. flies or moths); 7 % have bimodal pollination systems, whilst the remaining approx. 20 % are insect generalists. The less phenotypically specialized flowers of the Rauvolfioids are pollinated by a more restricted set of pollinators than are more complex flowers within the Apocynoids + Periplocoideae + Secamonoideae + Asclepiadoideae (APSA) clade. Certain combinations of bimodal pollination systems are more common than others. Some pollination systems are missing from particular regions, whilst others are over-represented.Within Apocynaceae, interactions with pollinators are highly structured both phylogenetically and biogeographically. Variation in transition rates between pollination systems suggest constraints on their evolution, whereas regional differences point to environmental effects such as filtering of certain pollinators from habitats. This is the most extensive analysis of its type so far attempted and gives important insights into the diversity and evolution of pollination systems in large clades
The diversity and evolution of pollination systems in large plant clades: Apocynaceae as a case study
Background and Aims Large clades of angiosperms are often characterized by diverse interactions with pollinators, but how these pollination systems are structured phylogenetically and biogeographically is still uncertain for most families. Apocynaceae is a clade of >5300 species with a worldwide distribution. A database representing >10 % of species in the family was used to explore the diversity of pollinators and evolutionary shifts in pollination systems across major clades and regions. Methods The database was compiled from published and unpublished reports. Plants were categorized into broad pollination systems and then subdivided to include bimodal systems. These were mapped against the five major divisions of the family, and against the smaller clades. Finally, pollination systems were mapped onto a phylogenetic reconstruction that included those species for which sequence data are available, and transition rates between pollination systems were calculated. Key Results Most Apocynaceae are insect pollinated with few records of bird pollination. Almost three-quarters of species are pollinated by a single higher taxon (e.g. flies or moths); 7 % have bimodal pollination systems, whilst the remaining approx. 20 % are insect generalists. The less phenotypically specialized flowers of the Rauvolfioids are pollinated by a more restricted set of pollinators than are more complex flowers within the Apocynoids + Periplocoideae + Secamonoideae + Asclepiadoideae (APSA) clade. Certain combinations of bimodal pollination systems are more common than others. Some pollination systems are missing from particular regions, whilst others are over-represented. Conclusions Within Apocynaceae, interactions with pollinators are highly structured both phylogenetically and biogeographically. Variation in transition rates between pollination systems suggest constraints on their evolution, whereas regional differences point to environmental effects such as filtering of certain pollinators from habitats. This is the most extensive analysis of its type so far attempted and gives important insights into the diversity and evolution of pollination systems in large clades
Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study
Summary
Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally.
Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies
have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of
the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income
countries globally, and identified factors associated with mortality.
Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to
hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis,
exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a
minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical
status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary
intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause,
in-hospital mortality for all conditions combined and each condition individually, stratified by country income status.
We did a complete case analysis.
Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital
diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal
malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome
countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male.
Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3).
Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income
countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups).
Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome
countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries;
p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients
combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11],
p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20
[1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention
(ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety
checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed
(ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of
parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65
[0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality.
Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome,
middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will
be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger
than 5 years by 2030
Una especie nueva de Tabernaemontana (Apocynaceae: Rauvolfioideae) de México, seriamente amenazada en su hábitat A new species of Tabernaemontana (Apocynaceae: Rauvolfioideae) from Mexico, seriously threatened in its habitat
Se describe una especie nueva de Tabernaemontana L. (Apocynaceae; Rauvolfioideae) del estado de Oaxaca, México. El presente taxón se distingue de las demás especies mexicanas del género por presentar frutos muricados. Se proporciona un mapa de su distribución y comentarios relativos a su estado de conservación.A new species of Tabernaemontana L. (Apocynaceae; Rauvolfioideae), from the state of Oaxaca, Mexico, is described. The new taxon can be distinguished from the other Mexican species of the genus by the presence of muricate fruits. A distribution map and comments about its risk status are provided
A new tropical species of <em>Aphyllon</em> (Orobanchaceae: Orobancheae) from Chiapas, Mexico
Background: Aphyllon is a genus of 25 root-holoparasitic species restricted to the Americas. It has a disjunct distribution, with 21 species distributed in North America and four in South America. Aphyllon is divided into two sections: Aphyllonand Nothaphyllon. All species of the genus have host-specificity, make it a study model in the evolution of holoparasitic plants. Recently, observations of a putative new species of Aphyllon were detected on iNaturalist.
Questions: Are the alluded iNaturalist observations of Aphyllon supported as a new species? What characters distinguish this taxon from the other species of Aphyllon?
Studied species: Taxa of Aphyllon section Nothaphyllon.
Study site and dates: Mexico; 2020–2023.
Methods: Specimens were collected, dissected, measured, photographed and preserved. Herbarium specimens and literature on Aphyllon were reviewed. Comparisons of the taxon with species of section Nothaphyllon’s were performed.
Results: A new species of the holoparasitic Aphyllon (Orobanchaceae) is described and illustrated. It is the second species of tropical humid vegetation in Mexico, an atypical environment for most of the genus, and it is the only species of the section with racemes with narrowed to nearly closed corolla mouths, and straight, non-revolute lobes of the lower lip.
Conclusions: The records in the citizen science platform have been useful to illustrate the morphology and color of the organisms, as well as to propose new species of Aphyllon. The photographs provide information not found in herbarium specimens due to oxidation and discoloration that occurs when drying Orobanchaceae plants
Cascabela Rafinesque 1838
Key of the species of Cascabela 1 Leaves with inconspicuous secondary venation.................................................................................................................................2 - Leaves with conspicuous secondary venation....................................................................................................................................4 2 Leaves obovate to oblanceolate, membranaceous to subleathery, glabrous; flowers greenish-yellow................ Cascabela gaumeri - Leaves filiform, linear to lanceolate, membranaceous, glabrous or sparsely puberulent; flowers yellow or orange........................3 3 Leaves sessile, linear to filiform, sparsely puberulent on both surfaces; inflorescence peduncles 8–30 mm...... Cascabela pinifolia - Leaves petiolate, lanceolate to elliptic-lanceolate, glabrous on both surfaces; inflorescence peduncles 3–9 mm............................................................................................................................................................................................................. Cascabela thevetia 4 Leaves obovate to oblanceolate, leathery.................................................................................................................. Cascabela ovata - Leaves linear-lanceolate to elliptic-lanceolate, membranaceous to subcoriaceous............................................................................5 5 Leaves pubescent on both surfaces, lower corolla tube 8–12 mm.................................................................... Cascabela balsaensis - Leaves glabrous adaxially, sparsely tomentulose abaxially, lower corolla tube 20–30 mm........................... Cascabela thevetioidesPublished as part of Alvarado-Cárdenas, Leonardo O. & Núñez, José Carmen Soto, 2014, A new species of Cascabela (Apocynaceae; Rauvolfioideae, Plumerieae) from Michoacán, Mexico, pp. 163-170 in Phytotaxa 177 (3) on page 169, DOI: 10.11646/phytotaxa.177.3.4, http://zenodo.org/record/514469