Search results for "Biogeography"
showing 10 items of 310 documents
Taxonomic investigation on Allium hirtovaginum group (Amaryllidaceae) from East Mediterranean area
2021
Within taxonomic studies on Allium sect. Codonoprasum from Mediterranean flora, populations belonging to A. hirtovaginum Candargy group were examined. Based on field investigation and herbarium surveyes, this group is represented by very critical and not well known taxa, distributed in the East Mediterranean, showing a marked morphological variability. Currently, the species referable to this group in addition to A. hirtovaginum are also A. pilosum Sibth. & Sm., A. aeginiense Brullo, Giusso & Terrasi and A. nerimaniae Koçyiğit & Kaya. Besides, other 13 species are here described as new to science, they are A. pythagoricum, A. pignattii, A. hippocraticum, A. abanticum, A. velutin…
Reconciling fossils and molecules: Cenozoic divergence of cichlid fishes and the biogeography of Madagascar
2001
Aim The biogeographical origins of the extant vertebrates endemic to Madagascar are largely unsolved, but have often been related to vicariance in the context of fragmentation of the supercontinent Gondwana in the Mesozoic. Such hypotheses are especially appealing in the case of cichlid fishes, which show phylogenetic relationships reflecting the temporal successions of the breakup of Gondwana. We used molecular clock data to test this assumption. Location Fragments of the 16S rRNA gene and of the nuclear Tmo-4C4 locus, partly obtained from Genbank from South American, African, Malagasy and Indian cichlids were analysed. Methods Based on monophyletic cichlid radiations in African lakes, we …
Areas of endemism in the Antarctic - a case study of the benthic hydrozoan genusOswaldella(Cnidaria, Kirchenpaueriidae)
2010
Aim The aim of this study is to investigate areas of endemism within the distribution of Oswaldella species in the Southern Ocean, thereby testing previous hypotheses and proposing alternative scenarios for Antarctic evolution. Location Southern Ocean, Antarctic and sub-Antarctic waters of southern South America. Methods We prepared a database for the 31 currently known species of the Antarctic genus Oswaldella, which includes geographical locations gathered from published taxonomic studies as well as materials from museums and expeditions. A parsimony analysis of endemicity (PAE) was used to test hypotheses of distribution patterns. Results Four areas of endemism are hypothesized: southern…
Benthic hydroids from off Low Island (Southern Ocean, Antarctica)
2013
A survey of marine benthic community biodiversity off Low Island (Southern Ocean) was carried out by the Spanish Antarctic Expedition Bentart 2006, using the BIO Hesperides. Samples from the expedition included an important collection of hydroids. A total of 39 species was recorded, two of them being new to science (Eudendrium bentart sp. nov., and Orthopyxis curiosa sp. nov.), belonging to the subclasses Anthoathecata and Leptothecata. Anthoathecates are represented by only two species, both referable to the genus Eudendrium. The 37 leptothecate species belong to the families Campanulinidae, Lafoeidae, Haleciidae, Schizotrichidae, Kirchenpaueriidae, Sertulariidae and Campanulariidae. Sertu…
Lymnaea schirazensis, an Overlooked Snail Distorting Fascioliasis Data: Genotype, Phenotype, Ecology, Worldwide Spread, Susceptibility, Applicability
2011
BackgroundLymnaeid snails transmit medical and veterinary important trematodiases, mainly fascioliasis. Vector specificity of fasciolid parasites defines disease distribution and characteristics. Different lymnaeid species appear linked to different transmission and epidemiological patterns. Pronounced susceptibility differences to absolute resistance have been described among lymnaeid populations. When assessing disease characteristics in different endemic areas, unexpected results were obtained in studies on lymnaeid susceptibility to Fasciola. We undertook studies to understand this disease transmission heterogeneity.Methodology/principal findingsA ten-year study in Iran, Egypt, Spain, t…
Genetic and phytochemical difference between some Indian and Italian plants of Whitania somnifera (L.) Dunal
2007
The geographical distribution of Withania somnifera (L.) Dunal is quite wide. However, in Italy. this species is very rare and grows spontaneously only in Sicily and in Sardinia. The PCR-RAPD technique has been utilized in this work to determine the genetic relationship among Sicilian, Sardinian and Indian samples and the HPLC analysis of whitaferin A was used as a marker to evaluate the phytochemical differences. The genetic difference between Indian and Sicilian plants of W. somnifera turned out to be smaller than that between Indian and Sardinian plants of this species. The phytochemical analysis as well showed that the Sardinian specimen strongly differed from the Indian and Sicilian on…
Leaps and bounds: geographical and ecological distance constrained the colonisation of the Afrotemperate by Erica.
2018
Abstract Background The coincidence of long distance dispersal (LDD) and biome shift is assumed to be the result of a multifaceted interplay between geographical distance and ecological suitability of source and sink areas. Here, we test the influence of these factors on the dispersal history of the flowering plant genus Erica (Ericaceae) across the Afrotemperate. We quantify similarity of Erica climate niches per biogeographic area using direct observations of species, and test various colonisation scenarios while estimating ancestral areas for the Erica clade using parametric biogeographic model testing. Results We infer that the overall dispersal history of Erica across the Afrotemperate…
Kretzoiarctos gen. nov., the oldest member of the giant panda clade
2012
The phylogenetic position of the giant panda, Ailuropoda melanoleuca (Carnivora: Ursidae: Ailuropodinae), has been one of the most hotly debated topics by mammalian biologists and paleontologists during the last century. Based on molecular data, it is currently recognized as a true ursid, sister-taxon of the remaining extant bears, from which it would have diverged by the Early Miocene. However, from a paleobiogeographic and chronological perspective, the origin of the giant panda lineage has remained elusive due to the scarcity of the available Miocene fossil record. Until recently, the genus Ailurarctos from the Late Miocene of China (ca. 8–7 mya) was recognized as the oldest undoubted me…
The evolutionary history of the rediscovered Austrian population of the giant centipede Scolopendra cingulata Latreille 1829 (Chilopoda, Scolopendrom…
2014
The thermophilous giant centipede Scolopendra cingulata is a voracious terrestrial predator, which uses its modified first leg pair and potent venom to capture prey. The highly variable species is the most common of the genus in Europe, occurring from Portugal in the west to Iran in the east. The northernmost occurrences are in Hungary and Romania, where it abides in small isolated fringe populations. We report the rediscovery of an isolated Austrian population of Scolopendra cingulata with the first explicit specimen records for more than 80 years and provide insights into the evolutionary history of the northernmost populations utilizing fragments of two mitochondrial genes, COI and 16S, …
On Daphnia (Ctenodaphnia) similis Claus, 1876 and other interesting anomopods (Crustacea Branchiopoda) from Apulia (southern Italy)
2007
The presence of Daphnia species in Apulia (southern Italy) freshwaters is updated