Anders S. Barfod

Twenty-five years of progress in understanding pollination mechanisms in palms (Arecaceae)

BACKGROUND With more than 90 published studies of pollination mechanisms, the palm family is one of the better studied tropical families of angiosperms. Understanding palm-pollinator interactions has implications for tropical silviculture, agroforestry and horticulture, as well as for our understanding of palm evolution and diversification. We review the rich literature on pollination mechanisms in palms that has appeared since the last review of palm pollination studies was published 25 years ago. SCOPE AND CONCLUSIONS Visitors to palm inflorescences are attracted by rewards such as food, shelter and oviposition sites. The interaction between the palm and its visiting fauna represents a trade-off between the services provided by the potential pollinators and the antagonistic activities of other insect visitors. Evidence suggests that beetles constitute the most important group of pollinators in palms, followed by bees and flies. Occasional pollinators include mammals (e.g. bats and marsupials) and even crabs. Comparative studies of palm-pollinator interactions in closely related palm species document transitions in floral morphology, phenology and anatomy correlated with shifts in pollination vectors. Synecological studies show that asynchronous flowering and partitioning of pollinator guilds may be important regulators of gene flow between closely related sympatric taxa and potential drivers of speciation processes. Studies of larger plant-pollinator networks point out the importance of competition for pollinators between palms and other flowering plants and document how the insect communities in tropical forest canopies probably influence the reproductive success of palms. However, published studies have a strong geographical bias towards the South American region and a taxonomic bias towards the tribe Cocoseae. Future studies should try to correct this imbalance to provide a more representative picture of pollination mechanisms and their evolutionary implications across the entire family.

Homoplasious character combinations and generic delimitation: a case study from the Indo-Pacific arecoid palms (Arecaceae: Areceae).

The complex distributions of morphological character states in the Indo-Pacific palm tribe Areceae (Arecaceae; Arecoideae) are potentially challenging for the delimitation of its genera. In the first exhaustive sampling of all 65 genera of the Areceae, we examined relationships of two of the tribes most problematic genera, Heterospathe and Rhopaloblaste, using portions of the low-copy nuclear genes phosphoribulokinase (PRK) and RNA-polymerase II subunit B (RPB2). Both genera fell within a highly supported clade comprising all Areceae genera, but are clearly unrelated. Rhopaloblaste was strongly supported as monophyletic and is most closely related to Indian Ocean genera. Heterospathe was resolved with strong support within a clade of western Pacific genera, but with the monotypic Alsmithia nested within it. Ptychosperma micranthum, which has previously been included in both Heterospathe and Rhopaloblaste, is excluded from these and from Ptychosperma, supporting its recent placement in a new genus Dransfieldia. Morphological comparisons indicate that the crownshaft is putatively synapomorphic for the Areceae with numerous reversals within the clade and some independent origins elsewhere. The putative diagnostic characters of Heterospathe show high levels of homoplasy, and the genus can only be distinguished by a suite of characters, whereas Rhopaloblaste is more clearly defined. Our results have implications not only for the two genera in focus, but have also been influential for the new classification of the Areceae.

Trade in Palm Products in North-Western South America

More than 200 scientific publications and Internet sources dealing with trade in palm products in north-western South America are reviewed. We focus on value chains, trade volumes, prices, and recent developments for some of the most important raw materials derived from native palms. Trade in palm products takes place at local, regional, national, and international levels. For local communities and individual households palm products may play a key role as the most important or only source of cash income. Most of these palm products are inadequately or not at all captured in trade statistics at the local and regional economic levels. Only products such as vegetable ivory and palm heart are monitored statistically, mainly because they are exported. Most raw materials derived from palms are extracted from the wild, and mainly by destructive harvesting. Reduced availability and rising prices on local and regional markets reflect incipient resource depletion. Only in vegetable ivory more or less sustainable wild harvesting methods prevail. Palm heart is increasingly being harvested from orchards and non-sustainable exploitation of wild populations is loosing ground. The international market for native palm oils and pulp (esp. Euterpe oleracea or açaí) is currently served almost exclusively from Brazil. Due to low oil contents and high production costs palm oils are currently used mainly for cosmetics. Based on their content of protein, starch, tocols, and carotenoids palm fruits have high nutritional value and represent a considerable potential for the development of functional foods, food supplements and animal fodder. Palms could undoubtedly play a more important role in the socio-economic development of north-western South America. Sustainability and marketing potential of palm products are negatively affected by the low income obtained by primary producers which often represents no more than 0.01–3% of the retail value. Poor governance, insecurity of land tenure and unequal sharing of profits endanger a sustainable long-term development of these valuable resources.ResumenSe revisan más de 200 publicaciones científicas y fuentes en Internet relacionadas con el comercio de productos de palmas en el noroeste de América del Sur. Nos enfocamos en las cadenas de valor, los volúmenes del comercio, los precios y el desarrollo reciente de algunas de las materias primas más importantes derivadas de las palmas. El comercio de productos de palmas se lleva a cabo a nivel local, regional, nacional e internacional. Para las comunidades locales y las familias individuales los productos de las palmas pueden desempeñar un papel clave como la fuente más importante o única de ingreso de dinero en efectivo, y esta importancia no se refleja adecuadamente en estadisticas oficiales. Los productos de las palmas se registran inadecuadamente en las estadísticas del comercio a nivel económico local y regional. Solamente los productos de palmas como el marfil vegetal y el meollo de palma son las que se monitorean estadísticamente debido principalmente a que son de exportación. La mayoría de las materias primas derivadas de las palmas se extraen de la naturaleza, principalmente por cosecha destructiva. La menor disponibilidad y el aumento de los precios en los mercados locales y regionales reflejan el agotamiento incipiente de los recursos. En el marfil vegetal prevalecen en mayor o menor medida técnicas de cosecha sostenible. Cada vez con mayor frecuencia el palmito se está cosechando de los huertos y la explotación no-sostenible de las poblaciones silvestres está perdiendo terreno. En la actualidad, el mercado internacional del aceite de palma nativa y la pulpa (especialmente Euterpe oleracea u açaí) está surtido casi exclusivamente por Brasil. Debido al contenido bajo de aceite y a los altos costos de producción, actualmente los aceites de palma se utilizan principalmente para cosméticos. Los frutos de las palmas tienen un alto valor nutricional (proteínas, almidón, tocols, carotenoides) y tienen un gran potencial para el desarrollo de alimentos funcionales, complementos alimenticios así como forraje para animales. Las palmas podrían desempeñar indudablemente un papel más importante en el desarrollo socio-económico del noroeste de América del Sur. La sostenibilidad y la comercialización potencial de los productos de las palmas son afectadas negativamente por los bajos ingresos obtenidos por los productores primarios de las materias primas (tipicamente 0.01 a 3% del precio de venta). La deficiente gestión gubernamental, la inseguridad de la tenencia de la tierra y la distribución desigual de los beneficios ponen en peligro el desarrollo sostentable a largo plazo de estos recursos valiosos.

Economic botany of Spondias purpurea (Anacardiaceae) in Ecuador.

The edible fruits of Spondias purpurea are valued highly throughout the Ecuadorian coastal plain and Andes where they are cultivated. They are also exported to Colombia and Peru. The fruits are either eaten fresh or processed into various products such as marmalade, wine, and liquor, all with promising market potential. This paper describes the annual cultivation cycle including, propagation, harvest and processing, yields, and socioeconomic importance of the fruits. In 1995, the total volume of the harvest in Ambuquí, province of Imbabura, was 130 000 kg with an average yield of 3250 kg/ha. Gross earnings was 472 US

The genus Licuala (Arecaceae; Coryphoideae) in Thailand

/ha. The net gain was 314 US

Xylem anatomical trait variability provides insight on the climate-growth relationship of Betula nana in western Greenland

/ha which represents six times the official monthly minimum wage in Ecuador. Spondias purpurea can grow and develop normally on rocky substrates and other marginal soils of otherwise low agricultural value.RésuméLos frutos comestibles de Spondias purpurea son muy apreciados en la región de la Costa y en los Andes de Ecuador en donde se cultivan. También se exportan a Colombia y Perú. Losfrutos se consumen en fresco o se procesan en varios productos como mermelada, vino y licor, todos ellos con un mercado potencial promisorio. En este trabajo se describe el ciclo anual de cultivo, que incluye su propagación, cosecha y procesado, producción e importancia socioeconómica de los frutos. En 1995, el volumen total de la cosecha en Ambuquí, provincia de Imbabura, fue de 130 000 kg con un promedio de producción de 3250 kg por hectarea. Los beneficios totales fueron de 472 dólares/ha. La ganancia neta fue de 314 dólares/ha, lo que representa seis veces el salario mensual mínimo oficial de Ecuador. Spondias purpurea puede crecer y desarrollarse con normalidad en sustratos pedregosos y otras àreas marginales de escaso valor agrícola.

Floral structure and organogenesis of the wax palm Ceroxylon ceriferum (Arecaceae; Ceroxyloideae).

The palm genus Licuala is revised for Thailand. Thirteen species are recognised mainly occurring in the understorey of rainforests in peninsular Thailand. Six recently described species are reduced to synonymy. Licuala merguensis, L. modesta, L. pusilla and L. scortechinii are new records from Thailand. Notes on distribution, ecology, vernacular naming, taxonomy and conservation status are provided. A synoptic key based on 26 characters is also provided.

A New, Dioecious, Dimorphic Species of Licuala (Palmae) from Hainan, China

ABSTRACT Climate change has been reported to affect shrub growth positively at several sites at high northern latitudes, including several arctic environments. The observed growth rates are, however, not uniform in space and time, and the mechanistic drivers of these patterns remain poorly understood. Here we investigated spatio-temporal interactions between climatic conditions, xylem anatomical traits, and annual growth of 21 Betula nana L. individuals from western Greenland for the period 2001–2011. Structural equation modeling showed that summer precipitation and winter temperature are affecting annual growth positively. Furthermore, vessel lumen area and vessel grouping, which are related to water conductivity and hydraulic connectivity of the xylem, respectively, positively influenced annual growth. To optimize growth B. nana was thus able to adjust its water transporting system. Annual variation in vessel lumen area seemed to be driven mostly by spring and summer temperatures, whereas annual variation in vessel grouping was driven by winter temperature. Linear models did not reveal a pattern in the spatial variation of xylem anatomical traits across the sampled climatic gradient. However, growth was positively correlated with local variation in insolation. Our results suggest that B. nana can adjust its hydraulic capacity to annual fluctuations in climatic conditions in order to optimize its total radial stem growth rate.

Pollen morphology of Ammandra, Palandra and Phytelephas (Arecaceae).

PREMISE OF THE STUDY Most palm systematists were surprised when molecular evidence pointed to a sister group relationship between the tribe Ceroxyleae and the phytelephantoid palms. The latter comprises three genera of morphological aberrant palms that have previously been considered a subfamily of their own. Here we present the results of a detailed study of the floral structure and development of the wax palm, Ceroxylon ceriferum, which aims at revealing derived traits shared by the sister tribes Ceroxyleae and Phytelepheae. METHODS A series of floral stages were sampled from Ceroxylon ceriferum growing in the central coastal range of Venezuela. The samples were prepared for scanning electronic microscopy and serial anatomical sectioning. KEY RESULTS The development of male and female flowers of Ceroxylon ceriferum was similar. The receptacle elongated early in the ontogeny. The perianth was differentiated into distinct sepals and petals and was characterized by a lack of postgenital fusion. The stamens were incepted centripetally in 2(-3) whorls. The outer whorl of three stamens was antesepalous. The inner whorl consisted of six stamens arranged in three antepetalous pairs. CONCLUSIONS The flowers of Ceroxylon ceriferum share a lack of postgenital fusion in the perianth with members of the tribe Phytelepheae. The elongation of the receptacle is reminiscent of the receptacle expansion in Phytelepheae. However, the multistaminate condition in C. ceriferum is less extreme than in the Phytelepheae, and the stamen initiation is centripetal as opposed to centrifugal in the latter.

Molecular phylogeny of the cosmopolitan aquatic plant genus Limosella (Scrophulariaceae) with a particular focus on the origin of the Australasian L. curdieana

Abstract A description and illustration of a new species of Licuala, L. hainanensis, from Hainan, China is given. This species, endemic to Hainan, was previously confused with the widespread L. spinosa. The distribution of the new species is mapped, and it is compared and contrasted to morphologically similar species from Vietnam. Evidence is presented that L. hainanensis is both dioecious and sexually dimorphic, based on its flower and rachilla morphology. Other potential cases of sexual dimorphism in Licuala are discussed.