Suchergebnisse

Se presenta un nuevo listado de la biota terrestre de las isletas más orientales del archipiélago canario (Roque del Este, Roque del Oeste, Montaña Clara, Alegranza, La Graciosa y Lobos) resultado de una exhaustiva recopilación bibliográfica y de bases de datos. El listado incluye briófitos, plantas vasculares, hongos, cordados, artrópodos y moluscos. Un breve análisis estadístico de la flora y fauna de los islotes revela que existen algo más de 700 especies en el conjunto de los mismos, la gran mayoría de ellas nativas, con más de un 25% de endemismos y menos de un 10% de especies exóticas, lo que avala la alta calidad de estos espacios protegidos. Con diferencia los taxa que más contribuyen a la biodiversidad inventariada son los artrópodos y las plantas vasculares, como ocurre en el resto del archipiélago. Hasta siete taxones diferentes, cuatro especies de araña, un ave –ya extinta–, un molusco y una planta vascular, son endémicos de estas isletas. La disponibilidad de esta lista contribuirá a la realización de análisis biogeográficos más rigurosos, pues hasta ahora la biota de las isletas no se encontraba desagregada de las islas mayores, Lanzarote y Fuerteventura, a las que pertenecen políticamente. ; A new checklist of the terrestrial biota from the easternmost islets from Canary Islands (Roque del Este, Roque del Oeste, Montaña Clara, Alegranza, La Graciosa and Lobos) isprovided as a result of a wide bibliographic and database compilation. The checklist includes bryophytes, vascular plants, fungi, chordates, arthropods and mollusks. Additionally, a short analysis of the fauna and flora species richness reveals that there are slightly more than 700 terrestrial species in the islets, the big majority of them being native, with > 25% endemics and < 10% exotics, what argues in favour of the high conservation quality of this protected area. By far, the more important taxa contributing to this biodiversity are arthropods and vascular plants, as happen in the rest of the archipelago. Up to seven different taxa, four spiders, one bird –already extinct–, one snail and one vascular plant, have been found to be endemic to the islets. Finally, the availability of this new checklist will contribute significantly towards more accurate biogeographic analyses of the Canarian biota, because until now the islets' biota distribution was not disaggregated of the main islands, Lanzarote and Fuerteventura, to which politically belong.

A new checklist of the terrestrial biota from the easternmost islets from Canary Islands (Roque del Este, Roque del Oeste, Montaña Clara, Alegranza, La Graciosa and Lobos) isprovided as a result of a wide bibliographic and database compilation. The checklist includes bryophytes, vascular plants, fungi, chordates, arthropods and mollusks. Additionally, a short analysis of the fauna and flora species richness reveals that there are slightly more than 700 terrestrial species in the islets, the big majority of them being native, with > 25% endemics and < 10% exotics, what argues in favour of the high conservation quality of this protected area. By far, the more important taxa contributing to this biodiversity are arthropods and vascular plants, as happen in the rest of the archipelago. Up to seven different taxa, four spiders, one bird –already extinct–, one snail and one vascular plant, have been found to be endemic to the islets. Finally, the availability of this new checklist will contribute significantly towards more accurate biogeographic analyses of the Canarian biota, because until now the islets' biota distribution was not disaggregated of the main islands, Lanzarote and Fuerteventura, to which politically belong. Se presenta un nuevo listado de la biota terrestre de las isletas más orientales del archipiélago canario (Roque del Este, Roque del Oeste, Montaña Clara, Alegranza, La Graciosa y Lobos) resultado de una exhaustiva recopilación bibliográfica y de bases de datos. El listado incluye briófitos, plantas vasculares, hongos, cordados, artrópodos y moluscos. Un breve análisis estadístico de la flora y fauna de los islotes revela que existen algo más de 700 especies en el conjunto de los mismos, la gran mayoría de ellas nativas, con más de un 25% de endemismos y menos de un 10% de especies exóticas, lo que avala la alta calidad de estos espacios protegidos. Con diferencia los taxa que más contribuyen a la biodiversidad inventariada son los artrópodos y las plantas vasculares, como ocurre en el resto del archipiélago. Hasta siete taxones diferentes, cuatro especies de araña, un ave –ya extinta–, un molusco y una planta vascular, son endémicos de estas isletas. La disponibilidad de esta lista contribuirá a la realización de análisis biogeográficos más rigurosos, pues hasta ahora la biota de las isletas no se encontraba desagregada de las islas mayores, Lanzarote y Fuerteventura, a las que pertenecen políticamente.

Understanding patterns of community structure and the causes for their variation can be furthered by comparative biogeographic analyses of island biotas. We used woody plant data at the local scale to investigate variations in species rarity, alpha, beta, and gamma diversity within and between three islands from the oceanic archipelagoes of Azores, Canaries and Mascarene. We used standardized protocols to sample ten 50 m × 50 m forest plots in each of the three islands with contrasting climate and regional species pools: Terceira (Azores), Tenerife (Canaries), and Reunion (Mascarene Islands). Occupancy frequency distributions and species abundance distributions were used to investigate rarity. The partitioning of beta diversity in a distance-decay framework was used to test for spatial patterns of community composition. Rarity was much more pronounced in the highly diverse islands of Tenerife and Reunion than in the regionally poorer island of Terceira. The number of species rose faster with increasing sample area in both Tenerife and Reunion. The slope of the species rank abundance curve was steeper in Terceira whereas the richer island assemblages approached a lognormal model. Compositional changes according to spatial distance were mostly due to replacement of species in Terceira and Reunion. Our results point to important differences in the community structure of Terceira, which is the less diverse and temperate region in comparison to Tenerife and Reunion which are highly diverse. ; This research was supported by the ERA-Net Net -Biome research framework, financed through the: Canary Islands Government ACIISI grants SE-12/02 (PO), SE-12/03 (JCC), SE-12/04 (BE), co-financed by FEDER; Portuguese FCT-NETBIOME grant 0003/2011 (PB); French ANR-NETBIOME grant n°11-EBIM-001-01 (CT); Région Reunion council for research activities (DS), Universitéde La Reunion contract DGADD/PE/20120585 (DS). CR, FR and IRA were supported by grants from Fundação da Ciência e Tecnologia - FCT-SFRH/BPD/91357/2012, FCT-PTDC/BIA-BIC/119255/2010, FCT-SFRH/BPD/102804/2014 respectively. MF has been funded by Direcção Regional da Ciência e Tecnologia, DRCT-M3.1.7/F/002/2011 and the Conselho Nacional de Desenvolvimento Científico e Tecnológico-CNPq (401045/2014-5), Programa Ciência sem Fronteiras; the current MF's contract is supported by the Universidad de Alcalá. The work of LBD in this manuscript was performed within the scope of the project MOMENTOS (PTDC/BIA-BIC/5558/2014). ; Peer Reviewed