The origin and speciation of orchids Pérez‐Escobar, Oscar A.; Bogarín, Diego; Przelomska, Natalia A. S. ...
The New phytologist,
April 2024, Letnik:
242, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Summary
Orchids constitute one of the most spectacular radiations of flowering plants. However, their origin, spread across the globe, and hotspots of speciation remain uncertain due to the lack of ...an up‐to‐date phylogeographic analysis.
We present a new Orchidaceae phylogeny based on combined high‐throughput and Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, and c. 7% (1921) of the 29 524 accepted species, and use it to infer geographic range evolution, diversity, and speciation patterns by adding curated geographical distributions from the World Checklist of Vascular Plants.
The orchids' most recent common ancestor is inferred to have lived in Late Cretaceous Laurasia. The modern range of Apostasioideae, which comprises two genera with 16 species from India to northern Australia, is interpreted as relictual, similar to that of numerous other groups that went extinct at higher latitudes following the global climate cooling during the Oligocene. Despite their ancient origin, modern orchid species diversity mainly originated over the last 5 Ma, with the highest speciation rates in Panama and Costa Rica.
These results alter our understanding of the geographic origin of orchids, previously proposed as Australian, and pinpoint Central America as a region of recent, explosive speciation.
Se describe e ilustra una nueva especie del género Pleurothallis para la región Andina colombiana llamada P. villahermosae, perteneciente a la subsección Macrophyllae-Fasciculatae. La nueva especie ...es morfológicamente similar a Pleurothalis callosa, de la cual se diferencia por tener el sépalo dorsal y el sinsépalo ovado-elíptico; pétalos falcado-lanceolados, acuminados y el labelo cuadrangular-ovado con presencia de 2 callos basales que ocupan un tercio de la longitud del labelo (vs. sépalo dorsal elíptico y sinsépalo ampliamente ovado y labelo unguiculado con 2 callos basales que se extienden hasta la mitad de la longitud del labelo en P. callosa). Se proporciona información geográfica, características ecológicas y estado de conservación de la nueva especie.
Ampelocera percyhernandezii, a new tree species restricted to dry forest remnants located inside inter-Andean valleys in the upper Magdalena River basin (Cundinamarca and Tolima departments), is ...described and illustrated. The new taxon is proposed here based on a literature survey, examination of numerous herbarium exssicatae, and field observations. Ampelocera percyhernandezii is morphologically similar to A. albertiae, A. longissima and A. macphersoni. However, the differences between these species are contrasted in the diagnosis, discussion, Table 1, and the species key. The figures show fresh and dried material and a geographical distribution map based on occurrence records. Following the IUCN assessment tool, the conservation status of A. percyhernandezii is provisionally determined as endangered (EN). Additionally, habitat information, phenology, the vernacular names, and a key to the species of Ampelocera are provided. This new species raises to ten the number of Ampelocera taxa. Colombia has the highest diversity of the genus with seven species.
A new species of cedar (Cedrela gonzalopalominoi) is described and illustrated, and its morphological relationships with other similar species are discussed. C. gonzalopalominoi is found in dry ...forest remnants in the Western Andean foothills and on the slopes of the Central Cordillera of Colombia. This is a region composed of low hills and plains systems inside inter-Andean valleys in the upper Magdalena River in the Department of Tolima. The new species is a tree up to 20 m tall and shares features with two species, C. odorata and C. weberbaueri. However, it can be distinguished by the leaflet numbers, pubescence, size and shape, inflorescences, pedicels, calyx, fruit size, and corolla lobes that are short pilose externally and fused to the androgynophore from the middle up. A morphological description, taxonomic comments, an illustration, and information about its current conservation status are presented. An updated key of 21 neotropical species of Cedrela is provided. Una nueva especie de cedro (Cedrela gonzalopalominoi) es descrita, ilustrada y sus relaciones morfológicas con sus especies afines son discutidas. C. gonzalopalominoi, se encuentra en remanentes de bosques secos sobre pendientes y pie de monte del sector occidental de la Cordillera central de Colombia. Esta región posee un sistema de lomeríos y planicies situadas en los valles interandinos, en el alto río Magdalena, departamento del Tolima. Esta nueva especie es un árbol de hasta 20 m de altura, que presenta similitudes morfológicas con dos especies (C. odorata y C. weberbaueri). Sin embargo, se distingue de estas especies en el número, pubescencia, tamaño y forma de los folíolos, en el tamaño de las inflorescencias, pedicelos, calíz y frutos, los lóbulos de la corola son pilosos externamente, los cuales están fusionados al androginóforo arriba de la mitad. Se presenta una descripción morfológica, comentarios taxonómicos, una ilustración e información acerca de su estado actual de conservación. Se incluye una clave de las 21 especies de Cedrela presentes en el Neotrópico.
Abstract A new species of Pleurothallis that belongs to the Macrophyllae-Fasciculatae from the Colombian Andes region is described and illustrated. The new species is morphologically similar to ...Pleurothallis callosa from which it can be differentiated by having its ovate-elliptic dorsal sepal and synsepal; falcate-lanceolate, acuminate petals and the quadrangular-ovate lip with two bas al calli that extend up to a third the length of the lip (vs. dorsal sepal elliptic and synsepal widely ovate and unguiculate lip with two basal calli that extend up to half the length of the lip in P. callosa). Geographic information, ecological characteristics, and conservation status of the new species are provided.
Los bosques secos tropicales son ecosistemas complejos y frágiles con alta intervención antrópica y ciclos reproductivos restringidos. Albergan riqueza, diversidad estructural, fisiológica y ...fenológica únicas. Esta investigación se desarrolló en el valle del Alto Magdalena, en cuatro fragmentos de bosque con diferentes estados sucesionales. En cada fragmento se establecieron cuatro parcelas permanentes de 0.25 ha y se evaluó el hábitat lumínico asociado a la riqueza, abundancia relativa y rareza de especies, al igual que la dinámica del bosque que contempló mortalidad, reclutamiento y crecimiento diamétrico para un periodo de 5.25 años. En bosque ribereño maduro se encontró una riqueza de especies mayor a la reportada en otros estudios para áreas similares en el Valle del Cauca y la Costa Atlántica. Se evidencian valores de riqueza, heterogeneidad y rareza de especies mayores que los encontrados para zonas más secas del Tolima. La estructura, diversidad y dinámica del bosque se correlacionaron con el hábitat lumínico, mostrando diferencias en la arquitectura del dosel y su papel en la captura y absorción de radiación. Bosques con dosel denso presentan poca disponibilidad de radiación fotosintética activa en el sotobosque, relacionado con baja riqueza de especies, mientras que sotobosques iluminados son más ricos y heterogéneos.
Tropical dry forests are complex and fragile ecosystems with high anthropic intervention and restricted reproductive cycles. These have unique richness, structural diversity, physiological and ...phenological . This research was executed in the Upper Magdalena Valley, in four forest fragments with different successional stages. In each fragment four permanent plots of 0.25 ha were established and lighting habitat associated with richness, relative abundance and rarity of species. The forest dynamics included the mortality, recruitment and diameter growth for a period of 5.25 years. The species rischness found in the mature riparian forestis higher than that reported in other studies of similar areas in Valle del Cauca and the Atlantic coast. The values of richness, diversity and rarity species are more evidenced than the magnitudes found in drier areas of Tolima. The structure, diversity and dynamics of forests were correlated with the lighting habitat, showing differences in canopy architecture and its role in the capture and absorption of radiation. Forests with dense canopy have limited availability of photosynthetically active radiation in understory related low species richness, while illuminated undergrowth are richer and heterogeneous.
In Colombia, dry tropical forests represents one of the most degraded, fragmented and less studied ecosystems, constituting a priority research element, therefore, in this paper, we defined the list ...of plants for dry forests in the department of Tolima supported by TOLI Herbarium collections and records of the authors, which were obtained in botanical expeditions over the last 4 years at these forests. The best sampled municipalities and the places without collections were defined. For the first time for this ecosystem, we registered in Colombia and South America Ophellantha spinosa Standl in The Neme Reserve in Coello, in dry forest in Tolima to Anthodon decussatum Ruiz & Pav., Gustavia santanderiensis R.Knuth and Simira rubescens (Benth.) Bremek. ex Steyerm. During curatorial process of collection, two isotypes were found to be determined, corresponding to Trichilia oligofoliolata M. E. Morales and Trichilia carinata M. E. Morales, these were considered endemic to the dry forests of northern Tolima. We conclude that the best collected places are agricultural research centers and they have generally historical collections including mainly species associated with crops such as weeds and grassland. Thus, forests that are not part of large monocultures in the fertile terraces are partly unexplored and could harbor important and unknown species to the area.
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