Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Asunto de la revista
País de afiliación
Intervalo de año de publicación
1.
PLoS One ; 12(7): e0181437, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28727847

RESUMEN

New Caledonia is a biodiversity hotspot, with an extremely high number of endemic species with narrow distribution ranges that are at high risk of extinction due to open-cast nickel mining, invasive species and seasonal man-induced fires. Mentions of micro-endemism permeate the literature on the biota of this archipelago. However, so far there has been no research comparing distribution range in different animal groups. The aim of this study is to examine the implication of different sampling effort variables in order to distinguish micro-endemicity from data deficiency, and evaluate the distribution range, frequency, and extent to which micro-endemism is common to several groups of organisms. We compiled a dataset derived from publications in Zoologia Neocaledonica, comprising 1,149 species, of which 86% are endemic to New Caledonia. We found that the sampling effort variables that were best correlated with distribution range were the number of sampling dates and the number of collectors per species. The median value of sampling dates was used to establish a cut-off point for defining adequately sampled species. We showed that, although only 52% of species were sampled adequately enough to determine their distribution range, the number of species with a very narrow distribution range was still high. Among endemics from New Caledonia, 12% (116 species) have ranges ≤5.2km2 and 3.9% (38 species) have ranges between 23 and 100 km2. Surprisingly, a similar trend was observed in non-endemic species: 22% occurred in areas ≤ 5.2 km2, and 8% in areas 23-100 km2, suggesting that environmental dissimilarity may play an important role in the distribution of these species. Micro-endemic species were predominant in 18 out of 20 orders. These results will contribute to a re-assessment of the IUCN red list of species in this archipelago, indicating that at least 116 species are probably critically endangered.


Asunto(s)
Distribución Animal , Biodiversidad , Animales , Clasificación , Conservación de los Recursos Naturales , Conjuntos de Datos como Asunto , Nueva Caledonia
2.
Sci Rep ; 7(1): 3705, 2017 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-28623347

RESUMEN

For a long time, New Caledonia was considered a continental island, a fragment of Gondwana harbouring old clades that originated by vicariance and so were thought to be locally ancient. Recent molecular phylogenetic studies dating diversification and geological data indicating important events of submergence during the Paleocene and Eocene (until 37 Ma) brought evidence to dismiss this old hypothesis. In spite of this, some authors still insist on the idea of a local permanence of a Gondwanan biota, justifying this assumption through a complex scenario of survival by hopping to and from nearby and now-vanished islands. Based on a comprehensive review of the literature, we found 40 studies dating regional clades of diverse organisms and we used them to test the hypothesis that New Caledonian and inclusive Pacific island clades are older than 37 Ma. The results of this meta-analysis provide strong evidence for refuting the hypothesis of a Gondwanan refuge with a biota that originated by vicariance. Only a few inclusive Pacific clades (6 out of 40) were older than the oldest existing island. We suggest that these clades could have extinct members either on vanished islands or nearby continents, emphasizing the role of dispersal and extinction in shaping the present-day biota.


Asunto(s)
Biodiversidad , Evolución Molecular , Islas , Filogenia , Modelos Teóricos
3.
Zootaxa ; 3948(1): 71-92, 2015 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-25947764

RESUMEN

This study is a catalogue of Dictyoptera (Mantodea, Isoptera and Blattaria) from five Eastern Mediterranean countries (Syria, Lebanon, Turkey, Iraq and Jordan). There are 75 species of Dictyoptera known to occur in these countries. These species belong to 15 families (eight of Mantodea, four of Isoptera and three of Blattaria). Mantodea is by far the dictyopteran group with the highest richness with 43 species occurring in this region, followed by Blattaria, with 21, and Isoptera with 11. Turkey is the place with the highest number of Dictyoptera (34%), followed by Iraq (23%) then Syria (22%), Jordan (15%) and Lebanon (7%). An analysis of accumulated number of species along time shows that most of this biodiversity was described during the 20th century, and that Mantodea is the group with the highest number of species described more recently. If this curve is taken as an estimator of the increase of diversity with new prospections, this indicates that the number of Mantodea in this region would be much higher than presently known. Conversely, the local richness of Blattaria and Isoptera are likely to be close to the present numbers, as the curves remain steady for about 100 years. An accumulation curve of species described with occurrence restricted to these five countries shows that most of them were described at the beginning of the 20th century. An analysis of the number of references dealing with each of these species along time reveals that Mantodea is the dictyopteran group most studied in all periods except the second half of the 20th century, when Isoptera was more cited. The types of these species are distributed in 29 institutions, but are mainly concentrated in four major European collections.


Asunto(s)
Cucarachas/clasificación , Distribución Animal , Animales , Femenino , Masculino , Región Mediterránea
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA