Lankesteriana

Relación Fenología-Clima De Cuatro Especies De Orquídeas En Un Bosque Altoandino De Colombia

ResumenEl objetivo de esta investigación fue caracterizar, durante un ciclo anual, la relación fenología-clima de cuatro especies comunes de orquídeas en un bosque altoandino de la Cordillera Oriental colombiana. Se monitoreó mensualmente la floración y la fructificación de 30 individuos adultos de Cyrtochilum revolutum, Malaxis excavata, Ponthieva diptera y Stelis pulchella. El número de flores en botón, flores abiertas, frutos inmaduros (cápsula cerrada) y el número de frutos maduros (cápsula abierta) se correlacionaron con las variables climáticas precipitación media mensual, temperatura media, mínima y máxima mensuales y humedad relativa mensual del mismo período de estudio. Los resultados mostraron que las cuatro especies de orquídeas presentaron actividad reproductiva durante el año de seguimiento. C. revolutum sólo floreció y se correlacionó de forma positiva con la precipitación. El pico de floración de S. pulchella, ocurrió en los meses más fríos y con menor humedad relativa. En contraste, la producción de frutos verdes se presentó en los momentos de mayor humedad y mayor temperatura, mientras que la apertura de las cápsulas ocurrió en los meses más secos. M. excavata presentó un patrón de floración y de fructificación extendido y el mayor número de flores abiertas se correlacionó de forma positiva con la precipitación. La producción de frutos verdes se correlacionó con la humedad relativa y la precipitación de dos meses atrás. Aunque P. diptera mostró pocos individuos en flor y en fruto, la actividad reproductiva se correlacionó con la precipitación y con la temperatura. A pesar de que la relación entre las variables climáticas y la fenología es diferente entre las especies, para tres de las cuatro especies estudiadas (C. revolutum, M. excavata y P. diptera) fue consistente la ocurrencia de la mayor floración durante la época de lluvias con correlaciones positivas significativas, aspecto que se discute a la luz de estudios previos.

AbstractThe objective of this research was to characterize, during an annual cycle, the relationship between weather and the phenology of four common orchid species in a high-Andean forest of the Eastern Cordillera of Colombia. Flowering and fruiting of 30 adult individuals of Cyrtochilum revolutum, Malaxis excavata, Ponthieva diptera and Stelis pulchella were monitored on a monthly basis. The number of flowering buds, open flowers, unripe and ripe fruits (closed and open capsule, respectively) were correlated to climatic variables (i.e. mean monthly precipitation, mean, minimum and maximum monthly temperature and, relative humidity) obtained during the same time period. The results showed that all orchid species exhibited reproductive activity during the studied year. C. revolutum only flowered, and was positively correlated with rainfall. The flowering peak of S. pulchella, occurred during the coldest months when relative humidity was also low. In contrast, the peak of unripe fruits was recorded when both the relative humidity and mean temperature were the highest, while capsules opened during the driest months. Flowering and fruiting of M. excavata were extended, lasting more than four months. The greatest number of open flowers was positively correlated to precipitation, while the number of unripe fruits was correlated with relative humidity and rainfall of twomonths prior. Few individuals of P. diptera flowered and fruited during the studied year, while reproductive activity was correlated to rainfall and temperature. Although the relationship between climatic variables and phenology is differential between species, our findings consistently showed that three out of four of the studied species (C. revolutum, M. excavata y P. diptera) flowered during the rainy season with significant positive correlations, which is discussed in light of literature findings.

Orchid Distribution and Bioclimatic Niches as a Strategy to Climate Change in Areas Of Tropical Dry Forest In Colombia

AbstractClimate change projections in Colombia predict an average increase in temperature of 2.6°C and in precipitation of 20% by the end of the century. These changes would directly affect the tropical dry forest (TDF) and its biodiversity. Epiphytic orchids, more exposed to the atmosphere than the terrestrial biota, remain dependent on climatic variables, making them particularly susceptible to climate change. We studied the spatial and temporal changes of a focal group of 12 orchid species typical of the TDF in Colombia, and the future conservation areas to this ecosystem. The algorithm used by MaxEnt was employed for modelling. A total of 439 records: direct observations (276); herbaria collections (159) and bibliographical sources (4) collected since September 2009 to April 2015 were considered for use in training the model. The actual potential niche was compared to the SRES 8.5 climate change emissions scenario for two periods: 2020-2049 (2030) and 2040-2069 (2050). The results indicate an altitudinal displacement compared to the present, conditioned by variables such as temperature, accessibility and precipitation. Mid-mountain areas (1300-1700 m) increased their idoneity in future potential niche models (2030 and 2050) to the detriment of the lowlands (0-1000 m). Other variables analysed, such as distance thresholds of pollinators (Euglossini), availability of phorophytes, and distances to TDF cover and protected areas, all suggest an improving connectivity between the lowland and mid-mountain areas. Consequently, bioclimatic niches (BN) are proposed as a new landscape management unit. Throughout the country, 69 of these BN were located as an adaptation-conservation strategy against climate change in the TDF in Colombia.

ResumenLas proyecciones del cambio climático en Colombia, indican en promedio un incremento en 2.6°C de temperatura y 20% de la precipitación para el fin del siglo. Estos cambios afectarán directamente al bosque seco tropical (Bs-T) y su biodiversidad. Las orquídeas epífitas, más expuestas a la atmósfera que la biota terrestre mantienen dependencia de variables ligadas al clima. Esta condición las hace particularmente susceptibles al cambio climático. Nosotros estudiamos los cambios espacio-temporales de un grupo focal de 12 especies de orquídeas típicas del Bs-T en Colombia y las futuras áreas de conservación de este ecosistema. El algoritmo usado por MaxEnt fue empleado para el modelamiento. Un total de 439 registros: observaciones directas (276); registros de herbario (159) y fuentes bibliográficas (4), colectadas desde septiembre de 2009 hasta abril 2015 fueron consideradas para entrenar el modelo. El nicho potencial actual fue comparado con el escenario de emisiones de cambio climático SRES 8.5 para dos periodos: 2020-2049 (2030) y 2040-2069 (2050). Los resultados indican un desplazamiento altitudinal respecto al presente, condicionado por variables como: temperatura, accesibilidad, y precipitación. Las áreas de montaña media (1300-1700 m) incrementarán su idoneidad en los modelos de nicho potencial futuro (2030 y 2050) en detrimento de las tierras bajas (0-1000 m). Otras variables analizadas como umbrales de distancia en polinizadores (Euglossini), disponibilidad de forófitos, distancias a coberturas de Bs-T y áreas protegidas, sugieren mejorar la conectividad entre tierras bajas y áreas de montaña media. En consecuencia, los nichos bioclimáticos (BN) son propuestos como nueva unidad de manejo del paisaje. En todo el país, 69 de ellos fueron localizados como estrategia de adaptación-conservación frente al cambio climático en áreas de Bs-T en Colombia.

Porroglossum Raoi , a New Species of Pleurothallidinae (Orchidaceae) From Ecuador

AbstractA new species of Porroglossum (Pleurothallidinae), Porroglossumraoi Baquero & Iturralde, apparently endemic to a cloud forest close to Chical, is described here. Porroglossumraoi is compared to known species within the genus growing close to the area where it was discovered. The big white flower, the thick, subclavate and brown-purple lateral sepal tails, a single subacute angle on the lower margin of the petals and a strong cinnamon and clove smell, immediately separates this from other species in Porroglossum. Taxonomical and ecological notes are given.

A Showy New Platystele (Pleurothallidinae: Orchidaceae) From Northwest Ecuador

AbstractA new species of Platystele (Pleurothallidinae: Orchidaceae) is described from foothill forest in the province of Carchi in northwestern Ecuador. The species has relatively large flowers for the genus, with long slender sepaline tails. It resembles Platystele caudatisepala, but is distinguished from that species by the partially connate lateral sepals, the convex lip with reflexed tip and margins, the deflexed petals, sometimes with their tips touching behind the flower, the sepals with recurved margins, and the leaves long-petiolate.

ResumenSe describe una nueva especie de Platystele (Pleurothallidinae: Orchidaceae) de los bosques piemontanos de la provincia de Carchi en el noroccidente de Ecuador. Esta especie presenta flores relativamente grandes en relación a la mayoría de las especies del género, cuyas caudas de los sépalos son largas y delgadas. Es similar a Platystele caudatisepala pero se distingue de esa especie por sus sépalos laterales parcialmente connados, el labio convexo con la punta y márgenes reflexos, los pétalos deflexos, a veces tocando sus puntas hacia atrás de la flor, los sépalos con márgenes recurvados y las hojas largamente pecioladas.

Precursors of the Botanical Exploration of South America. Wilhelm Piso (1611-1678) and Georg Marcgrave (1610-1644)

AbstractThe Dutch colonization of northeastern Brazil from 1630 to 1654 is described, with emphasis on the years 1636-1644, when the colony was under the administration of Johan-Maurits Prince of NassauSiegen (1604-1679). During his rule, the Company sent the geographer and astronomer Georg Marcgrave (1610-1644) and the physician Willem Piso (1611-1644) to Recife. Both explored northern Brazil and made rich botanical and zoological collections, which were published in Amsterdam in 1648, after Pisos’s return, under the title Historia naturalis Brasiliae; a second edition followed in 1658. In this work Piso mentions for the first time the orchid Vanilla in its current spelling. Both Piso and Marcgrave collected and illustrated Catasetum maculatum L.C.R., whilst a third orchid species, Trigonidium acuminatum Batem., can be found in Marcgrave’s herbarium.

Novelties in the Orchid Flora of the Municipality Of Benedito Novo, Santa Catarina, Brazil, and an Updated Checklist

AbstractIn 2013, Caetano and colleagues published two lists of the Orchidaceae of the Municipality of Benedito Novo, Santa Catarina, totalling 99 species. Between January 2014 and September 2016, additional field trips were made and new species were found in the region. Thus, in this paper an updated checklist of the Orchidaceae of Benedito Novo is presented based on herbarium collections and field surveys. A total of 184 species distributed in 66 genera are registered, comprising about 35% of the species and 60% of the genera cited for Santa Catarina. The richest genera are Acianthera Scheidw. (18 species), Pabstiella Brieger & Senghas (14), Epidendrum L., Gomesa R.Br., and Maxillaria Ruiz & Pav. (13 each). A new combination and a lectotypification in the genus Pabstiella are proposed.