Estructura floral de la palma neotropical del género Chamaedorea (Arecoideae, Arecaceae)

Male and female floral structure has been studied in 28 species of Chamaedorea, the largest palm genus present in the Neotropics. The taxa investigated represent all subgenera according to the most recent taxonomic revision of the group. Morphological, histological and cytological features that are known to be of importance for interactions with visiting insects were studied and their putative role in protecting the flowering parts assessed. The taxonomic distribution of selected characters is in some cases congruent with relationships inferred by recently published molecular studies within the group.Se ha estudiado la estructura de las flores masculinas y femeninas en 28 especies de Chamaedorea, el género de palmas con mayor número de especies en la región neotropical. Los táxones investigados representan a todos los subgéneros contemplados en la más reciente revisión taxonómica del grupo. Se han estudiado los caracteres morfológicos, histológicos y citológicos de mayor importancia en cuanto a la visita de insectos y se ha examinado su rol dentro de la protección de los órganos florales. La distribución taxonómica de caracteres seleccionados ha demostrado, en algunos casos, ser congruente con las relaciones inferidas por los más recientes estudios moleculares que incluyen al grupo

Chamaedorea castillo-montii (Arecaceae), a new species from Guatemala

Volume: 68Start Page: 397End Page: 40

Two new species of Chamaedorea (Arecaceae) from Guatemala

Volume: 68Start Page: 390End Page: 39

Three new species of Chamaedorea (Arecaceae) from Oaxaca, Mexico

Volume: 68Start Page: 401End Page: 40

Chamaedorea: Diverse species in diverse habitats

Abstract Remarkably diverse species occurring in equally diverse habitats characterize Chamaedorea, a genus of about 90 dioecious species restricted to the understory of neotropical rain and cloud forests from Mexico to Bolivia and Ecuador. A vast array of habits, stems, leaves, inflorescences, flowers, and fruits reflect the diversity of species. Although the genus is most species-rich in dense, moist or wet, diverse forests from 800-1,500 meters elevation, a few exceptional species occur in open and/or seasonally dry forests, on harsh substrates, or in other unusual habitats.Diverses espèces dans divers habitats Résumé Des espèces extraordinairement diverses se trouvant dans des habitats également divers caractérisent Chamaedorea, un genre qui compte environ 90 espèces dioïqucs limitées aux sous-bois des forêts néo-tropicales constamment dans la pluie et les nuages, du Mexique à la Bolivie et à l'Équateur. Une vaste gamme de formes biologiques, de tiges, de feuilles, d'inflorescences, de fleurs, et de fruits reflète la diversité des espèces. Bien que le genre soit plus riche en espèces dans les forêts denses et humides situées entre 800-1,500 mètres d'altitude, quelque espèces exceptionnelles se trouvent dans des forêts moins denses et/ou occasionnellement sèches, sur des substances dures ou dans d'autres habitats inhabituels.Diversas especies en diversos hábitats Resumen Especies notablemente diversas presentes en habitats igualmente diversos caracterizan a Chamaedorea, un género de aproximademente 90 especies dioicas limitadas al sotobosque de los bosques lluviosos y nubosos neotropicalcs desde México hasta Bolivia y Ecuador. Una amplia gama de formas biológicas, tallos, hojas, inflorescencias, flores, y frutos refleja la diversidad de las especies. Aunque el género es más rico en especies en los bosques densos y húmedos de 800-1,500 metros de altura, unas pocas especies excepcionales ocurren en bosques abiertos u ocasionalmente secos, en substrato severo o en otros habitats extraordinarios.Hodel Donald R. Chamaedorea: Diverse species in diverse habitats. In: Bulletin de l'Institut Français d’Études Andines, tome 21, N°2, 1992. Les palmiers des forêts tropicales. pp. 433-458

Two new species of Chamaedorea (Arecaceae)

Volume: 7Start Page: 35End Page: 3

Exceptional trees of Los Angeles, ten years after

Volume: 1997-1998:winterStart Page: 1End Page:

Once in a lifetime: celebrating a botanical grand finale

Volume: 2013:summer/fallStart Page: 12End Page: 1

A remarkable new species and additional novelties of Chamaedorea from Costa Rica and Panamá. Notables nuevas especies y novedades adicionales de Chamaedorea de Costa Rica y Panamá

Three of the four new spp. of Chamaedorea (Arecaceae) described here are endemic (as far as is known) to Costa Rica. The "remarkable" one is C. piscifolia Hodel, G. Herrera & Casc., with simple, apically bifid and long-caudate, "fish-shaped" leaf-blades and infls. arising from the prostrate, often buried proximal portion of the stem. This is compared with the Guatemalan C. tuerckheimii (Dammer) Burret and, like that sp., has significant commercial potential. Because of that fact, the geographic range of C. piscifolia (and two of the other spp. described here) is deliberately concealed. The other new Costa Rican endemics are Chamaedorea incrustata Hodel, G. Herrera & Casc., most similar to C. pittieri L.H. Bailey, and C. rosibeliae Hodel, G. Herrera & Casc., compared especially with the sympatric C. anemophila Hodel. The type locality of C. rosibeliae is provided (Alto Urén, on the Atlantic slope of the Cordillera de Talamanca), presumably because it is so difficult of access. The remaining novelty, Chamaedorea rossteniorum Hodel, G. Herrera & Casc., is superficially similar to and has been confused with C. stricta Standl. & Steyerm., of northern Mesoamerica. However, the recent discovery of male flowers reveals that it is quite unrelated, belonging to a different subgenus. Chamaedorea rossteniorum has also been collected in Panama. All of the spp. are illustrated with superb color and black-and-white photos, mostly (except C. rosibeliae) of living specimens in the fieldUCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Comparative hydraulic and anatomic properties in palm trees (Washingtonia robusta) of varying heights: implications for hydraulic limitation to increased height growth

As trees grow taller, the energetic cost of moving water to the leaves becomes higher and could begin to limit carbon gain and subsequent growth. The hydraulic limitation hypothesis states that as trees grow taller, the path length and therefore frictional resistance of water flow increases, leading to stomatal closure, reduced photosynthesis and decreased height growth in tall trees. Although this hypothesis is supported by the physical laws governing water movement in trees, its validation has been complicated by the complex structure of most tree species. Therefore, this study tested the hydraulic limitation hypothesis in Washingtonia robusta (H. Wendl.), a palm that, while growing to tall heights, is still structurally simple enough to act as a model organism for testing. There were no discernable relationships between tree height and stomatal conductance, stomatal densities, guard cell lengths, leaf dry mass per unit area (LMA) or sap flux, suggesting that these key aspects of hydraulic limitation are not reduced in taller palms. Taller palms did, however, have higher maximum daily photosynthetic assimilation rates, lower minimum leaf water potentials that occurred earlier in the day and fewer, smaller leaves than did shorter palms. Leaf epidermal cells were also smaller in taller palms compared with shorter ones. These findings are consistent with hydraulic compensation in that tall palms may be overcoming the increased path length resistance through smaller, more efficient leaves and lower leaf water potentials than shorter palms