Ceroxylon weberbaueri Burret, a poorly known species, is recollected from its type locality. An amended des- cription is provided and the species is neotypified.

This article presents an inventory of South American palms including 457 species and 50 genera. The distribution of palms within seven phytogeographical entities is analyzed. Factors which influence the evolution of palms in South America are discussed.

The genus Hexopetion was described by Burret to accommodate a single species, H. mexicanum. We reinstate the genus on the basis of morphological and anatomical data, and enlarge it to include a second species, Astrocaryum alatum, for which a new combination is made.

The genus Attalea (Arecaceae) is distributed in continental habitats of the Neotropical region and in some Caribbean islands. Life forms of Attalea species vary from small acaulescent palms to tall and massive palms, always solitary. The ecological range of the genus encompasses most of the Neotropical ecosystems, from coastal sand dunes to sub-Andean forests up to 1600 m in elevation, lowland wet to dry forests, savannas, swamps, etc. The taxonomy of the genus has been poorly understood due to conflicting genus and species concepts that exist since the last decades. Taxonomical problems have been caused by the lack of adequate material, especially species of large size, loss of many types and difficulties in interpreting hybrids. In this article, I review the most recent taxonomic literature on Attalea. The number of species in Attalea varies from 29 to 67 depending on different authors...

Ceroxylon weberbaueri Burret, a poorly known species, is recollected from its type locality. An amended des- cription is provided and the species is neotypified.

This article presents an inventory of South American palms including 457 species and 50 genera. The distribution of palms within seven phytogeographical entities is analyzed. Factors which influence the evolution of palms in South America are discussed.

The genus Hexopetion was described by Burret to accommodate a single species, H. mexicanum. We reinstate the genus on the basis of morphological and anatomical data, and enlarge it to include a second species, Astrocaryum alatum, for which a new combination is made.

The genus Attalea (Arecaceae) is distributed in continental habitats of the Neotropical region and in some Caribbean islands. Life forms of Attalea species vary from small acaulescent palms to tall and massive palms, always solitary. The ecological range of the genus encompasses most of the Neotropical ecosystems, from coastal sand dunes to sub-Andean forests up to 1600 m in elevation, lowland wet to dry forests, savannas, swamps, etc. The taxonomy of the genus has been poorly understood due to conflicting genus and species concepts that exist since the last decades. Taxonomical problems have been caused by the lack of adequate material, especially species of large size, loss of many types and difficulties in interpreting hybrids. In this article, I review the most recent taxonomic literature on Attalea. The number of species in Attalea varies from 29 to 67 depending on different authors...

With the aim of testing the evolutionary relationships between Oenocarpus bataua (formerly Jessenia bataua) and other Oenocarpus species (Arecaceae), a phylogenetic study of tribe Euterpeae (Arecaceae) was conducted using 3,6 kb of non-coding chloroplast DNA sequence data. The results of maximum parsimony analysis support the monophyly of Euterpeae and the inclusion of O. bataua within the Oenocarpus clade. Our results show substantial molecular divergence between O. bataua var. bataua and var. oligocarpus suggesting that, according to their original description, these two taxa may indeed represent different species. However, our phylogenies should be considered as tentative due to low statistical support.

This study identifies a parapatric contact zone between Astrocaryum macrocalyx and Astrocaryum urostachys at the boundary between the Marañón-Pastaza flood plain and the Iquitos Arch, in the northern Peruvian Amazon. The area sampled covers 35,5 ha in the form of 9 transects 1-3 km long × 20 m wide. All Astrocaryum individuals were recorded within the transects, and their size was measured as well as topographical data of the environment. The results show that the two species meet only in a small area in the confluence zone of Marañón and Tigre rivers near the southwest basement of the Iquitos Arch. A total of 1133 Astrocaryum individuals were recorded, mostly in the 0—3,90 m size classes, with only 9,2% of the individuals exceeding 12 m in high. Within the three topographical positions considered (slope, valley bottom and ridge), most individuals were found in the lower slopes an...

With the aim of testing the evolutionary relationships between Oenocarpus bataua (formerly Jessenia bataua) and other Oenocarpus species (Arecaceae), a phylogenetic study of tribe Euterpeae (Arecaceae) was conducted using 3,6 kb of non-coding chloroplast DNA sequence data. The results of maximum parsimony analysis support the monophyly of Euterpeae and the inclusion of O. bataua within the Oenocarpus clade. Our results show substantial molecular divergence between O. bataua var. bataua and var. oligocarpus suggesting that, according to their original description, these two taxa may indeed represent different species. However, our phylogenies should be considered as tentative due to low statistical support.

This study identifies a parapatric contact zone between Astrocaryum macrocalyx and Astrocaryum urostachys at the boundary between the Marañón-Pastaza flood plain and the Iquitos Arch, in the northern Peruvian Amazon. The area sampled covers 35,5 ha in the form of 9 transects 1-3 km long × 20 m wide. All Astrocaryum individuals were recorded within the transects, and their size was measured as well as topographical data of the environment. The results show that the two species meet only in a small area in the confluence zone of Marañón and Tigre rivers near the southwest basement of the Iquitos Arch. A total of 1133 Astrocaryum individuals were recorded, mostly in the 0—3,90 m size classes, with only 9,2% of the individuals exceeding 12 m in high. Within the three topographical positions considered (slope, valley bottom and ridge), most individuals were found in the lower slopes an...

Detailed distribution of Astrocaryum sect. Huicungo (Arecaceae) in Peru is presented and discussed. Twelve out of the 15 species that compose this section are found in the Peruvian territory from North to South in the eastern Andean foothills and western Amazonian lowlands. All these species have a parapatric distribution, except for Astrocaryum macrocalyx and A. urostachys, which share a very limited area. Limits of distribution areas may be related to geographical, geomorphological and ecological barriers (river, geological rising, soil drainage). In some cases, however, the contact between species is almost contiguous; no natural barrier could be detected in the field.

The anatomy of fruit and perianth is described for 12 Peruvian species of the genus Astrocaryum. The fruit displays three well-defined layers: exocarp with fiber boundles and sclereids, free or grouped; mesocarp with parenchyma and schizogenous cavities; and heavily sclerified endocarp. Density of vascular bundles of the calyx is higher in the two species of subgenus Astrocaryum and lower in the ten species of subgenus Monogynanthus. Several structures exhibit useful characters for distinguishing subsections and species in the Huicungo section. Such characters include the form and location of fiber packages of the calyx, density of brachysclereids in the distal zone of the exocarp, form of vascular bundles of the corolla, raphides in the mesocarp, presence or absence of trichomes, structure of trichomes, presence or absence of laminar colenchyma in the exocarp, staminodial ring free or a...

Detailed distribution of Astrocaryum sect. Huicungo (Arecaceae) in Peru is presented and discussed. Twelve out of the 15 species that compose this section are found in the Peruvian territory from North to South in the eastern Andean foothills and western Amazonian lowlands. All these species have a parapatric distribution, except for Astrocaryum macrocalyx and A. urostachys, which share a very limited area. Limits of distribution areas may be related to geographical, geomorphological and ecological barriers (river, geological rising, soil drainage). In some cases, however, the contact between species is almost contiguous; no natural barrier could be detected in the field.

The anatomy of fruit and perianth is described for 12 Peruvian species of the genus Astrocaryum. The fruit displays three well-defined layers: exocarp with fiber boundles and sclereids, free or grouped; mesocarp with parenchyma and schizogenous cavities; and heavily sclerified endocarp. Density of vascular bundles of the calyx is higher in the two species of subgenus Astrocaryum and lower in the ten species of subgenus Monogynanthus. Several structures exhibit useful characters for distinguishing subsections and species in the Huicungo section. Such characters include the form and location of fiber packages of the calyx, density of brachysclereids in the distal zone of the exocarp, form of vascular bundles of the corolla, raphides in the mesocarp, presence or absence of trichomes, structure of trichomes, presence or absence of laminar colenchyma in the exocarp, staminodial ring free or a...

A new species of Ceroxylon from Peru, C. peruvianum, is described and illustrated. The finding of disjunctive populations of C. quindiuense in Peru is discussed.

A new species of Ceroxylon from Peru, C. peruvianum, is described and illustrated. The finding of disjunctive populations of C. quindiuense in Peru is discussed.

Originalmente, las palmeras son especies adaptadas al bosque tropical húmedo. Sin embargo existe un número significativo de especies adaptadas a ecosistemas caracterizados por algún grado de sequía. En América del Sur existen 130 especies adaptadas a ecosistemas relativamente secos, lo que dice de su capacidad de adaptación en relación a la limitación del recurso hídrico. Esta cualidad les permite adecuarse al contexto de disminución de las precipitaciones, uno de los aspectos del cambio climático en la región. Sin embargo, en América del Sur, el proceso de adaptación de las palmeras a los ecosistemas secos ha demorado entre 10 a 15 millones de años, y solamente 13 linajes de palmeras tuvieron la capacidad de pasar del bosque húmedo a ecosistemas secos lo cual sugiere que si bien son adaptables, también son poco flexibles para responder a cambios rápidos del clima.

El género Attalea presenta 56 de las 459 especies de palmeras sudamericanas y 28 desde Colombia a Bolivia. Se encuentran desde México a Bolivia, en diferentes tipos de vegetación: bosques húmedos bajos en vegetación secundaria y estacionalmente inundada y otras ecoregiones, bosques secos tipo sabana, matorral costero tropical, bosques húmedos tropicales y en bosques premontanos y montanos hasta los 1600 msnm. En la región amazónica es uno de los géneros típicos de significativas radiaciones a nivel específico junto a Bactris, Geonoma y Astrocaryum con alrededor de 28 especies, teniendo como rango altitudinal desde el nivel del mar hasta los 1600 msnm. En el Perú, Attalea ocurre en valles de las vertientes orientales con marcados endemismos y comparte con Bolivia ocho especies. En la Amazonía, la diversidad fenotípica de Attalea se basa en caracteres vegetativos observables ...