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In tropical regions, most primary ecosystems have been replaced by mosaic landscapes in which species must cope with a large shift in the distribution of their habitat and associated food resources. Primates are particularly vulnerable to habitat modifications. Most species persist in small fragments surrounded by complex human-mediated matrices whose structure and connectivity may strongly influence their dispersal and feeding behavior. Behavioral plasticity appears to be a crucial parameter governing the ability of organisms to exploit the resources offered by new matrix habitats and thus to persist in fragmented habitats. In this study, we were interested in the dietary plasticity of the golden-crowned sifaka (Propithecus tattersalli), an endangered species of lemur, found only in the Daraina region in north-eastern Madagascar. We used a DNA-based approach combining the barcoding concept and Illumina next-generation sequencing to (i) describe the species diet across its entire range and (ii) evaluate the influence of landscape heterogeneity on diet diversity and composition. Faeces from 96 individuals were sampled across the entire species range and their contents were analyzed using the trnL metabarcoding approach. In parallel, we built a large DNA reference database based on a checklist of the plant species of the Daraina region. Our results suggest that golden-crowned sifakas exhibit remarkable dietary diversity with at least 130 plant species belonging to 80 genera and 49 different families. We highlighted an influence of both habitat type and openness on diet composition suggesting a high flexibility of foraging strategies. Moreover, we observed the presence of numerous cultivated and naturalized plants in the faeces of groups living in forest edge areas. Overall, our findings support our initial expectation that P. tattersalli is able to cope with the current level of alteration of the landscape and confirm our previous results on the distribution and the dispersal ability of this species.

Desmochaeta (now Cyathula ) achyranthoides was described from South America and reported to be a widespread tropical plant in both Africa and the Americas. A revision of herbarium material revealed that inter alia leaf shape differs between the populations of the Eastern and Western Hemispheres. Therefore, we maintain the name C. achyranthoides s.str. for the American populations and re-instate the name C. geminata for most of the African plants. Both species are found in tropical evergreen forests, mainly at low altitudes. Furthermore, two mountain species, C. brevispicata from Madagascar and C. aethiopica from east tropical Africa, which were previously identified as C. achyranthoides , are described as new to science. Compared to both C. achyranthoides and C. geminata , these new species have short inflorescences and longer, recurved or uncinate perianths in the fertile flowers and morphologically resemble C. fernando-poensis ; the latter is only known from the mountains of Equatorial Guinea (Bioko Island), south-west and (newly recorded here) North-West Regions of Cameroon. The species under study are compared with one another and with the related, pantropically distributed species C. prostrata ; their synonymy is verified and typifications are established. The fine-level partial florescence (cyme) structure of each species is also studied, with further taxonomic implications. Cyathula geminata seems to be restricted to west and central tropical Africa, with its range replaced eastwards by C. aethiopica and in Madagascar by C. brevispicata .

(now ) was described from South America and reported to be a widespread tropical plant in both Africa and the Americas. A revision of herbarium material revealed that leaf shape differs between the populations of the Eastern and Western Hemispheres. Therefore, we maintain the name s.str. for the American populations and re-instate the name for most of the African plants. Both species are found in tropical evergreen forests, mainly at low altitudes. Furthermore, two mountain species, from Madagascar and from east tropical Africa, which were previously identified as , are described as new to science. Compared to both and , these new species have short inflorescences and longer, recurved or uncinate perianths in the fertile flowers and morphologically resemble ; the latter is only known from the mountains of Equatorial Guinea (Bioko Island), south-west and (newly recorded here) North-West Regions of Cameroon. The species under study are compared with one another and with the related, pantropically distributed species ; their synonymy is verified and typifications are established. The fine-level partial florescence (cyme) structure of each species is also studied, with further taxonomic implications. seems to be restricted to west and central tropical Africa, with its range replaced eastwards by and in Madagascar by .

Bogner J. & Nusbaumer L.: A new species of Carlephyton (Araceae) from northern Madagascar with notes on the species of this genus. — Willdenowia 42: 209–217. December 2012. — Online ISSN 1868-6397; © 2012 BGBM Berlin-Dahlem. Stable URL: http://dx.doi.org/10.3372/wi.42.42206 A new aroid species endemic to northern Madagascar, Carlephyton darainense, is described and illustrated. The new species differs from the similar C. madagascariense by the male flowers with laxly arranged synandria, each consisting of two stamens with the filaments basally connate but apically free and turned horizontally, and a long cylindric style in the female flowers, whereas in C. madagascariense the male flowers have densely arranged synandria, each consisting of two to six completely connate stamens, and a short conical style in female flowers. The distribution and ecology of C. darainense are briefly discussed, a comparison with the three other species of the genus and a key to all four species are included.

1. Comparative analyses of diversity variation among and between regions allow testing of alternative explanatory models and ideas. Here, we explore the relationships between the tree x-diversity of small rain forest plots in Africa and in Amazonia and climatic variables, to test the explanatory power of climate and the consistency of relationships between the two continents. 2. Our analysis included 1003 African plots and 512 Amazonian plots. All are located in old-growth primary non-flooded forest under 900 m altitude. Tree a-diversity is estimated using Fisher's alpha calculated for trees with diameter at breast height ≥ 10 cm. Mean diversity values are lower in Africa by a factor of two. 3. Climate-diversity analyses are based on data aggregated for grid cells of 2.5 x 2.5 km. The highest Fisher's alpha values are found in Amazonian forests with no climatic analogue in our African data set. When the analysis is restricted to pixels of directly comparable climate, the mean diversity of African forests is still much lower than that in Amazonia. Only in regions of low mean annual rainfall and temperature is mean diversity in African forests comparable with, or superior to, the diversity in Amazonia. 4. The climatic variables best correlated with the tree α-diversity are largely different in the African and Amazonian data, or correlate with African and Amazonian diversity in opposite directions. 5. These differences in the relationship between local/landscape-scale a-diversity and climate variables between the two continents point to the possible significance of an array of factors including: macro-scale climate differences between the two regions, overall size of the respective species pools, past climate variation, other forms of long-term and short-term environmental variation, and edaphics. We speculate that the lower a-diversity of African lowland rain forests reported here may be in part a function of the smaller regional species pool of tree species adapted to warm, wet conditions. 6. Our results point to the importance of controlling for variation in plot size and for gross differences in regional climates when undertaking comparative analyses between regions of how local diversity of forest varies in relation to other putative controlling factors.

Aim: Our aim was to evaluate the extent to which we can predict and map tree alpha diversity across broad spatial scales either by using climate and remote sensing data or by exploiting spatial autocorrelation patterns. Location: Tropical rain forest, West Africa and Atlantic Central Africa. Methods: Alpha diversity estimates were compiled for trees with diameter at breast height ≥ 10 cm in 573 inventory plots. Linear regression (ordinary least squares, OLS) and random forest (RF) statistical techniques were used to project alpha diversity estimates at unsampled locations using climate data and remote sensing data [Moderate Resolution Imaging Spectroradiometer (MODIS), normalized difference vegetation index (NDVI), Quick Scatterometer (QSCAT), tree cover, elevation]. The prediction reliabilities of OLS and RF models were evaluated using a novel approach and compared to that of a kriging model based on geographic location alone. Results: The predictive power of the kriging model was comparable to that of OLS and RF models based on climatic and remote sensing data. The three models provided congruent predictions of alpha diversity in well-sampled areas but not in poorly inventoried locations. The reliability of the predictions of all three models declined markedly with distance from points with inventory data, becoming very low at distances > 50 km. According to inventory data, Atlantic Central African forests display a higher mean alpha diversity than do West African forests. Main conclusions: The lower tree alpha diversity in West Africa than in Atlantic Central Africa may reflect a richer regional species pool in the latter. Our results emphasize and illustrate the need to test model predictions in a spatially explicit manner. Good OLS or RF model predictions from inventory data at short distance largely result from the strong spatial autocorrelation displayed by both the alpha diversity and the predictive variables rather than necessarily from causal relationships. Our results suggest that alpha diversity is driven by history rather than by the contemporary environment. Given the low predictive power of models, we call for a major effort to broaden the geographical extent and intensity of forest assessments to expand our knowledge of African rain forest diversity.

In tropical regions, most primary ecosystems have been replaced by mosaic landscapes in which species must cope with a large shift in the distribution of their habitat and associated food resources. Primates are particularly vulnerable to habitat modifications. Most species persist in small fragments surrounded by complex human-mediated matrices whose structure and connectivity may strongly influence their dispersal and feeding behavior. Behavioral plasticity appears to be a crucial parameter governing the ability of organisms to exploit the resources offered by new matrix habitats and thus to persist in fragmented habitats. In this study, we were interested in the dietary plasticity of the golden-crowned sifaka (Propithecus tattersalli), an endangered species of lemur, found only in the Daraina region in north-eastern Madagascar. We used a DNA-based approach combining the barcoding concept and Illumina next-generation sequencing to (i) describe the species diet across its entire range and (ii) evaluate the influence of landscape heterogeneity on diet diversity and composition. Faeces from 96 individuals were sampled across the entire species range and their contents were analyzed using the trnL metabarcoding approach. In parallel, we built a large DNA reference database based on a checklist of the plant species of the Daraina region. Our results suggest that golden-crowned sifakas exhibit remarkable dietary diversity with at least 130 plant species belonging to 80 genera and 49 different families. We highlighted an influence of both habitat type and openness on diet composition suggesting a high flexibility of foraging strategies. Moreover, we observed the presence of numerous cultivated and naturalized plants in the faeces of groups living in forest edge areas. Overall, our findings support our initial expectation that P. tattersalli is able to cope with the current level of alteration of the landscape and confirm our previous results on the distribution and the dispersal ability of this species.