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The study of how climatic niches change over evolutionary time has recently attracted the interest of many researchers. Different methodologies have been employed principally to analyze the temporal dynamics of the niche and specially to test for the presence of phylogenetic niche conservatism. Menonvillea, a genus of Brassicaceae including 24 species, is distributed primarily along the Andes of Argentina and Chile, with some taxa growing in southern Patagonia and others in the Atacama Desert and the Chilean Matorral. The genus is highly diversified morphologically but also presents a remarkably wide ecological range, growing from the high Andean elevations, to the dry coastal deserts in Chile, or the Patagonia Steppe in Argentina. In this study, we used molecular phylogenies together with climatic data to study climatic niche evolution in the genus. The results show that the main climatic niche shifts in Menonvillea occurred between the sections Cuneata-Scapigera and sect. Menonvillea throughout the Mid-Late Miocene, and associated with the two main geographical distribution centers of the genus: the highlands of the central-southern Andes and the Atacama Desert-Chilean Matorral, respectively. Climatic niches in these lineages were mainly differentiated by the aridity and potential evapotranspiration, the minimum temperatures of the coldest month, and the temperature annual range and seasonality. Niche evolution in Menonvillea deviated from a Brownian motion process, with most of the climatic dimension best-fitting to an Ornstein-Uhlenbeck model of multiple adaptive peaks. Our results also indicated that higher aridity levels and lower annual temperature ranges were associated with the evolution of the annual habit, as exemplified by the distribution of sect. Menonvillea. Finally, the results suggested that climatic niche evolution in Menonvillea exhibited some degree of phylogenetic niche conservatism, fundamentally within the two main lineages (sect. Menonvillea and sects. Cuneata-Scapigera).  相似文献   

3.
The nymphalid Paulogramma hydarnis (Godart) (n. comb., previously in the genus Callicore) is an endangered butterfly present in a few montane sites in the Atlantic Forest in the Southeastern Brazil. The precise systematic position of P. hydarnis was previously unknown. Based on molecular data, we find that it is sister to Paulogramma pygas (Godart) (n. comb., also previously in Callicore), a common and widespread species in the Neotropics. In addition, we find that Callicore is not monophyletic and that “Callicorehydarnis (along with other species) is more related to the genus Paulogramma, and should thus be placed in that genus. The genus Paulogramma is now composed by the following species: Paulogramma pyracmon (Godart), Paulogramma eunomia (Hewitson) n. comb., Paulogramma hydarnis (Godart) n. comb., Paulogramma hystaspes (Fabricius) n. comb., Paulogramma pygas (Godart) n. comb., and Paulogramma tolima (Hewitson, 1852) n. comb. Museum specimens and field data report P. hydarnis in four sites in Southeastern Brazil. Recently, P. hydarnis was recorded for the first time at Parque Nacional do Caparaó, states of Espírito Santo and Minas Gerais, expanding its distribution about 200 km northward of the previously known limit. Although regularly recorded in some sites, most records are historic, before the 1960s, and the current conservation situation of this species is delicate, deserving attention.  相似文献   

4.
The composition and distribution of the species of the genus Scalaspira Conrad, 1862 in the Eocene-Oligocene of western Kazakhstan are revised. Following Tembrock we assign this genus to Buccinidae and synonymize Aquilofusus Kautsky, 1925 with it. The stratigraphic interval studied contains at least eight species. Three species are new: S. alexeevi (Middle? and Upper Eocene, Chegan Formation), S. korobkovi, and S. kumsuatensis (Upper Oligocene, Karatomak Beds).  相似文献   

5.
We describe a new species of small-eared shrew, genus Cryptotis Pomel, 1848 (Eulipotyphla: Soricidae), from near the community of Monteverde in the Tilarán highlands of northwestern Costa Rica. The new species is immediately distinguished from all other Costa Rican shrews its large size and long tail. Morphologically, it belongs to the Cryptotis thomasi group of small-eared shrews, a clade that is more typically distributed in the Andes Cordillera and other highland regions of northern South America. The new Costa Rican species and the Panamanian endemic Cryptotis endersi Setzer, 1950 are the only two members of this species group known to occur in Central America. Like most other members of the C. thomasi group for which the postcranial skeleton has been studied, the new species tends be more ambulatory (rather than semi-fossorial) when compared with other members of the genus. Our survey efforts over several decades failed to locate a population of the new species, and we discuss its conservation status in light of its limited potential distribution in the Tilarán highlands and the significant climatic change that has been documented in the Monteverde region during the past four decades.  相似文献   

6.
The Patagonian silverside Odontesthes hatcheri is a native fish restricted to streams and lakes of Patagonia (Argentina and Chile). Stocking programs to enhance recreational fisheries in man-made reservoirs have introduced a nonnative, closely-related species (the pejerrey O. bonariensis) in Patagonia almost a century ago, and yet little is known about the invasiveness of this species. To evaluate the impact of these introductions we analyze genetic data (microsatellite markers and mitochondrial DNA) to quantify the incidence of hybridization between these two species and assess potential effects on native population structure. Phylogeographic analyses reveal weak geographic differentiation among populations of O. hatcheri, in agreement with previous studies for other freshwater fishes in Patagonia strongly influenced by Quaternary glaciations and hydrographic basin changes since the last glaciation. However, many populations have unique genetic pools. In several areas, introductions resulted in extensive hybridization, with high frequencies of F2 and backcrossed hybrids in natural populations, and in some cases O. bonariensis has completely displaced the native populations. The negative impact of these introductions on native populations is correlated to temperature, a critical parameter in the face of global warming, suggesting that invasiveness of O. bonariensis may increase in the future. Our results advise against continuing stocking programs to preserve the integrity of natural populations of the Patagonian silverside.  相似文献   

7.
Chikanda is a traditional dish made with wild-harvested ground orchid tubers belonging to three orchidioid genera, Disa, Satyrium and Habenaria, all of which are CITES appendix II-listed. Identification of collected orchid tubers is very difficult and documentation of constituent species in prepared chikanda has hitherto been impossible. Here amplicon metabarcoding was used in samples of six prepared chikanda cakes to study genetic sequence diversity and species diversity in this product. Molecular operational taxonomic unit identification using similarity-matching reveals that species of all three genera were present in the chikanda samples studied. Disa was present in all of the samples, Satyrium in five out of six and Habenaria in one of the samples, as well as a number of other plants. The fact that each sample contained orchids and the presence of a wide variety of species from all genera in this traditional dish raise serious concerns about the sustainability of this trade and the future of wild orchid populations in the main harvest areas. This proof-of-concept study shows that Ion-Torrent PGM is a cost-effective scalable platform for metabarcoding using the relatively long nrITS1 and nrITS2 regions. Furthermore, nrITS metabarcoding can be successfully used for the detection of specific ingredients in a highly-processed food product at genus level, and this makes it a useful tool in the detection of possible conservation issues arising from commercialized trade or processed plant products.  相似文献   

8.
Fungal spores are normal components of external environments. They have been reported to be associated with human, animal and plant diseases causing primary and opportunistic infections. Cladosporium is commonly the most frequently isolated genus from air samples, and its species are considered mainly saprophytic, but there is a wide variety of taxa that can cause adverse effects on human and animal health and also on plants. In this work, we aimed to record Cladosporium spores frequency of isolation in northern Argentinean Patagonia and to perform a molecular characterization based on actin gene complemented with EF1α and ITS genes. The ability of the pathogens to cause disease in pip fruits of Packham’s Triumph and Abate Fetel pears and red delicious apples was determined. Results confirmed Cladosporium spores as the main genera isolated from air samples, and the molecular characterization revealed the existence of 11 species in this region grouped in C. cladosporioides and C. herbarum complexes. Pathogenicity tests revealed that Cladosporium sp. cause disease on fruit. Abate Fetel was the most susceptible to infection. These results compose the first study in Argentina in respect of identification at species level of airborne Cladosporium spores, and furthermore, it is the first report in northern Patagonia and the high valley of Río Negro productive region. This knowledge can help farmers to take preventive measures in order to avoid biological damage.  相似文献   

9.
A new species of Stemodia (Plantaginaceae) from the Caatinga of northern Minas Gerais, Brazil, is described and illustrated. Stemodia perfoliata was first collected by Auguste de Saint-Hilaire, ca. 200 years ago, and remained unnamed until now. The new species is characterized by the connate-perfoliate leaves, a unique feature in the genus. We provide notes on morphology, geographic distribution and conservation status of S. perfoliata, along with a key to differentiate it from the similar species that occur in Brazil: S. durantifolia, S. hyptoides, S. maritima, S. palustris and S. stricta.  相似文献   

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Rosa odorata var. gigantea is one of the most important ancestors of modern roses, which owns many merit traits including large flower, early flowering, and tea scent. Due to habitat loss and fragmentation, it has been listed as a rare and endangered species in China. In this study, a total of 424 accessions from 27 locations across its major distribution range were sampled. Its genetic diversity and population structure were assessed using a combination of seven nuclear microsatellite markers and one single-copy nuclear gene. Moderate to high within-population genetic diversity and moderate differentiation among populations were revealed despite its narrow distribution. The sampled 27 populations were resolved into two genetic clusters with limited contemporary and historical gene flows. The Red River Fault Zone was inferred to be a physical or geographical barrier to gene flow between these two genetic clusters. Genetic distances were significantly associated with geographic distances, indicating the isolation-by-distance model. Our ecological niche modeling indicated that R. odorata var. gigantea had high current potential areas in the central Yunnan province and substantial losses of high potential distribution areas in the western Yunnan in the future. Two detected clusters showed significant genetic differentiation and represented two separate evolutionary lineages, which should be recognized as two evolutionary significant units (ESUs) for conservation concerns. These results could be applied for the decision-making and conservation planning for this important species.  相似文献   

12.
Based on light and scanning electron microscopical studies, a new nematode parasite, Pseudodelphis eleginopsis n. sp. (Dracunculoidea: Guyanemidae), is described from tissues behind the gills of the Patagonian blennie Eleginops maclovinus (Cuvier) (Perciformes: Eleginopsidae) off the Atlantic coast (San Matías and San José Gulfs) of Patagonia, Argentina. The new species is mainly characterised by the length of the body (males 10–13 mm, larvigerous females 31–59 mm), the number (14) and arrangement of cephalic papillae, the absence of a buccal capsule, the muscular to glandular oesophagus length ratio (1:3–4) of larvigerous females, the length of the spicules (48–63 µm) and the number (7 pairs) and arrangement of the caudal papillae in the male. Pseudodelphis eleginopsis n. sp. is the first species of this genus described from a marine fish in the Atlantic Ocean and the first known dracunculoid parasitising the fish host belonging to the family Eleginopsidae. As revealed by the examination of very young females of the new species, the female genital tract of Pseudodelphis spp. is monodelphic. The genus Syngnathinema Moravec, Spangenberg & Frasca, 2001 is considered a junior synonym of Pseudodelphis Adamson & Roth, 1990 and, consequently, S. californiense and S. chitwoodi are transferred to Pseudodelphis as P. californiensis (Moravec, Spangenberg & Frasca, 2001) n. comb. and P. chitwoodi (Moravec & Kuchta, 2013) n. comb., respectively. Two dracunculoid species, Pseudodelphis limnicola Brugni & Viozzi, 2006 and the previously established Philonema percichthydis Moravec, Urawa & Coria, 1997, both described from the same freshwater host species, Percichthys trucha (Valenciennes), in the same region (Patagonia), are considered to be identical; therefore, the valid name of this species is Pseudodelphis percichthydis n. comb. and P. limnicola becomes its junior synonym. A key to the species of Pseudodelphis is provided.  相似文献   

13.
A multivariate morphometric study of the genus Nicoraepoa was carried out to examine patterns of morphological variation among the species and to identify additional characters to allow a clearer delimitation among species. Nicoraepoa is a taxonomically complex genus comprising seven species endemic to South America. Although most of the species are well delimited, two of them, N. andina and N. chonotica, are morphologically similar and very difficult to separate. The morphological variation among species, with overlapping morphological characters, pseudovivipary and possible hybridization make species boundaries unclear. In the present paper, sixty-seven characters were scored for a total of 216 specimens and analyzed using ordination, cluster and discriminant analyses. Based on multivariate results, we recognized species groups and morphological diagnostic characters that allow clearer species delimitation. As a result, N. chonotica has been transferred to N. andina as a subspecies that inhabit southern Patagonia. Other taxa could be recognized and delimited by diagnostic characters: N. erinacea, N. pugionifolia, N. stepparia, N. subenervis subsp. spegazziniana and N. subenervis subsp. subenervis. Moreover, we discuss the possibility that a new species from Bolivia, based on only one specimen, closely related to N. subenervis should be ascribed in Nicoraepoa.  相似文献   

14.
In most eukaryotic species, centromeres harbor large arrays of tandem repeated satellite DNA sequences. In this study, we report on the genomic distribution of a centromere satellite repeat “MtR3” in Medicago genus and three distantly related genera. Fluorescence in situ hybridization (FISH) results showed MtR3 repeats were detected in the centromere regions in M. truncatula, M. minima, M. edgeworthii, M. ruthenica, M. caerulea, M. sativa, and M. falcata (4×), but no signals were discovered in M. lupulina, M. polymorpha, and M. falcata (2×), Melilotus officinalis, Crotalaria medicaginea, and Trifolium repens. However, sequence analysis showed this MtR3 DNA had genomic distribution in all species and was highly conserved across the entire Medicago genus and three other genera. The conservation and widespread presence suggested MtR3 repeats may play important roles in centromeric function.  相似文献   

15.
The Neotropical otter, Lontra longicaudis, is considered near threatened by the IUCN, and with declining populations, it is still one of the lesser known species of otter in the world. Like other otter species, L. longicaudis is associated with water courses in a large variety of habitats and biomes across its area of distribution. Here, we present a review of the available literature on L. longicaudis aiming to update information on its distribution, ecology and systematics. We performed online searches using combinations of the words L. longicaudis, river otter, Neotropical otter, nutria and lobito del río, limiting our search to 1972–2016. Recent information on evolutionary history and biogeographic patterns, distribution patterns, as well as on the ecology of the species across a large part of its distribution range, including trophic ecology and intraspecific communication, was retrieved. We found severe gaps in knowledge including aspects of life history, ground validation of new potential distribution areas and long-term population monitoring aiming at designing more efficient conservation measures and techniques. In this context, we conclude by presenting perspectives for future studies.  相似文献   

16.
The genus Porphyra (and its sister genus Pyropia) contains important red algal species that are cultivated and/or harvested for human consumption, sustaining a billion-dollar aquaculture industry. A vast amount of research has been focused on species of this genus, including studies on genetics and genomics among other areas. Twelve novel microsatellite markers were developed here for Porphyra linearis. Markers were characterized using 32 individuals collected from four natural populations of P. linearis with total heterozygosity varying from 0.098 to 0.916. The number of alleles per locus ranged from 2 to 18. All markers showed cross amplification with Porphyra umbilicalis and/or Porphyra dioica. These polymorphic microsatellite markers are useful for investigating population genetic diversity and differentiation in P. linearis and may become useful for other genetic research on the reproductive biology of this important species.  相似文献   

17.
The nucleotide sequences of the nuclear rDNA ITS regions were determined for 34 species of the genus Primula L. and one species of the genus Cortusa L., family Primulaceae Vent., and used to infer the phylogenetic relationships among these species. In this analysis species of the Russian flora and the flora of adjacent territories were studied for the first time. The results clarified the taxomic structure of the genus Primula and confirmed the entity of some of its sections; but not the subgenera sensu J.Richards. Our data do not support an independent status of the genus Cortusa, placing it as one of the terminal lineages of the section Cortusoides Balf. f. in the genus Primula.  相似文献   

18.
The genus Imbira Carbayo et al., 2013 encompasses two species, Imbira guaiana (Leal-Zanchet & Carbayo, 2001) and Imbira marcusi Carbayo et al., 2013, which occur in south Brazil, in areas originally covered by the Atlantic Forest. In the present study, we examine the genetic diversity within the genus, investigate the occurrence of molecular autapomorphies for its species and describe a new species for the genus based on an integrative approach. The Bayesian and maximum likelihood analyses based on DNA barcoding recovered the monophyly of the genus Imbira, but indicate that specimens representing I. marcusi correspond to five distinct lineages. These analyses, as well as sequence divergence data, revealed that the new species herein described is closely related to I. guaiana and that the specific status of specimens of I. marcusi available in GenBank should be reviewed. In addition, sequence analysis revealed 32 molecular autapomorphies for all independent evolutionary units within the genus. The new species described herein seems to be endemic to its type locality, a private area without legal protection.  相似文献   

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The genus Deporaus from the Russian fauna is revised. Four species (D. pacatus, D. azarovae, D. septentrionalis, and D. hartmanni) of the subgenera Pseudapoderites and Japonodeporaus are found. Keys to the subgenera and to the species of the subgenus Pseudapoderites are given. The genus Deporaus, subgenera Pseudapoderites and Japonodeporaus, and four species are redescribed. The distribution of these species in Russia is discussed.  相似文献   

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