Search results for " hotspot"

Understanding volcanoes in the Vanuatu arc

2016

We report the first helium isotope survey of volcanic gases, hot springs and some olivine phenocrysts along the Vanuatu island arc, from Tanna in the south to Vanua Lava in the north. Low CO2 content and low He-3/He-4 ratios in thermal fluids of Epi (4.0 +/- 0.1 R-a), Efate (4.5 +/- 0.1 R-a) and Pentecost (5.3 +/- 0.5 R-a) islands coherently indicate reduced mantle gas leakage and crustal contamination by radiogenic helium on these extinct volcanic systems of the former (Pliocene) arc. Instead, presently active Vanuatu volcanoes display He-3/He-4 and C/He-3 ratios typical of subduction-related volcanic arcs: He-3/He-4 ratios range from 6.4 +/- 0.5 Ra in southernmost Tanna and 7.23 +/- 0.09 …

Pilot biodiversity assessment of the Hkakabo Razi passerine avifauna in northern Myanmar – implications for conservation from molecular genetics

2019

SummaryThe Hkakabo Razi region located in northern Myanmar is an Important Bird Area and part of the Eastern Himalayan Biodiversity Hotspot. Within the framework of the World Heritage Convention to enlist the site under criterion (ix) and (x), we conducted a biodiversity assessment for passerine birds using DNA barcoding and other molecular markers. Of the 441 bird species recorded, we chose 16 target species for a comparative phylogeographic study. Genetic analysis was performed for a larger number of species and helped identifying misidentified species. We found phylogeographic structure in all but one of the 16 study species. In 13 species, populations from northern Myanmar were genetica…

Evaluation of the DNA barcoding approach to develop a reference data-set for the threatened flora of Sicily

2014

The Mediterranean Basin is one of the most significantly altered World Biodiversity Hotspots with extensive habitat loss and fast genetic population erosion, for which urgent biodiversity reconnaissance and preservation actions are required. In particular, Sicily has about 600 taxa classified as threatened or near-threatened. The correct recognition and identification of such biodiversity is required for supporting further activities. The objective of this work is to assess the ability of the DNA barcoding approach to identify different taxonomic groups from a collection of the most threatened plant taxa, throughout natural Sicilian populations. The evaluation of the DNA barcoding core mark…

Urgent need for preservation of grapevine (Vitis vinifera L. Subsp. vinifera) germplasm from small circum-Sicilian islands as revealed by SSR markers…

2016

Since the last decades grapevine germplasm is undergoing a process of rapid genetic erosion. This process is of particular concern in minor circum-Sicilian islands, because of the sharp reduction of the cultivated surfaces and the shift of their economy from agriculture to tourism. Aiming at valorising and preserving the surviving varieties we collected 185 accessions during several surveys since 2007. Six nuclear microsatellite markers were used for germplasm characterization, yielding 75 different genetic profiles. We found out that most genetic profiles (39) were not listed in national and international grapevine databases, confirming that the Sicilian minor islands represent underexplor…

Parallel bursts of recent and rapid radiation in the Mediterranean and Eritreo-Arabian biodiversity hotspots as revealed byGlobulariaandCampylanthus(…

2018

Diversity and endemism of woody plant species in the Equatorial Pacific seasonally dry forests

2009

The biodiversity hotspot of the Equatorial Pacific region in western Ecuador and northwestern Peru comprises the most extensive seasonally dry forest formations west of the Andes. Based on a recently assembled checklist of the woody plants occurring in this region, we analysed their geographical and altitudinal distribution patterns. The montane seasonally dry forest region (at an altitude between 1,000 and 1,100 m, and the smallest in terms of area) was outstanding in terms of total species richness and number of endemics. The extensive seasonally dry forest formations in the Ecuadorean and Peruvian lowlands and hills (i.e., forests below 500 m altitude) were comparatively much more specie…

ATLANTIC BIRDS: a data set of bird species from the Brazilian Atlantic Forest

2017

South America holds 30% of the world's avifauna, with the Atlantic Forest representing one of the richest regions of the Neotropics. Here we have compiled a data set on Brazilian Atlantic Forest bird occurrence (150,423) and abundance samples (N = 832 bird species; 33,119 bird individuals) using multiple methods, including qualitative surveys, mist nets, point counts, and line transects). We used four main sources of data: museum collections, on‐line databases, literature sources, and unpublished reports. The data set comprises 4,122 localities and data from 1815 to 2017. Most studies were conducted in the Florestas de Interior (1,510 localities) and Serra do Mar (1,280 localities) biogeogr…

Red Listing plants under full national responsibility: Extinction risk and threats in the vascular flora endemic to Italy

2018

Abstract Taxa endemic to a country are key elements for setting national conservation priorities and for driving conservation strategies, since their persistence is entirely dependent on national policy. We applied the IUCN Red List categories to all Italian endemic vascular plants (1340 taxa) to assess their current risk of extinction and to highlight their major threats. Our results revealed that six taxa are already extinct and that 22.4% (300 taxa) are threatened with extinction, while 18.4% (247; especially belonging to apomictic groups) have been categorized as Data Deficient. Italian endemic vascular plants are primarily threatened by natural habitat modification due to agriculture, …

An integrative approach challenges species hypotheses and provides hints for evolutionary history of two Mediterranean freshwater palaemonid shrimps …

2021

25 pages; International audience; The Mediterranean Region is a biodiversity/endemism hotspot whose freshwater fauna remains largely unexplored. Our integrative study challenges the taxonomic status of two freshwater palaemonid shrimps, Palaemon antennarius and Palaemon minos. Three molecular operational taxonomic units (MOTUs) were defined based on 352 cytochrome oxidase subunit I (COI) sequences and 88 haplotypes. Two belonged to P. antennarius: one inhabiting the Apennine Peninsula and Sicily, and the other from the Balkan Peninsula. Palaemon minos was the third MOTU, found on Crete. The Balkan MOTU of P. antennarius was genetically closer to P. minos than to the other conspecific MOTU. …

Fire and Plant Diversification in Mediterranean-Climate Regions

2018

Despite decades of broad interest in global patterns of biodiversity, little attention has been given to understanding the remarkable levels of plant diversity present in the world’s five Mediterranean-type climate (MTC) regions, all of which are considered to be biodiversity hotspots. Comprising the Mediterranean Basin, California, central Chile, the Cape Region of South Africa, and southwestern Australia, these regions share the unusual climatic regime of mild wet winters and warm dry summers. Despite their small extent, covering only about 2.2% of world land area, these regions are home to approximately one-sixth of the world vascular plant flora. The onset of MTCs in the middle Miocene …