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1.
Abstract

Sinusichnus Gibert 1996 Gibert, J. M. d. 1996. “A New Decapod Burrow System from the NW Mediterranean Pliocene.” Revista Española de Paleontología 11: 251254. [Google Scholar] is recorded for the first time in the Oligocene-Miocene Pirabas Formation of Northern Brazil. In these Oligocene-Miocene carbonate deposits, Sinusichnus sinuosus is characterized by horizontal, highly regular sinusoidal burrow systems with T- and H-shaped branching points. The main difference between the S. sinuosus described herein and other occurrences worldwide is the anomalous diameter of the burrows (4 to 10?cm). These trace fossils occur in organic matter-rich, wackestone/packstone and laminated mudstones interbedded with boundstones deposited in an inner carbonate platform paleoenvironment. The exceptional size of the studied S. sinuosus could have been associated to the producer’s size, which may be attributed to construction by large crustaceans, similar to fossils found within the Pirabas Formation. Also, the sinusoidal morphology and retrusive spreiten could be a result of the fodinichnial/domichnial behavior.  相似文献   

2.
ABSTRACT

Background

The genus Restrepia occurs throughout Central and South America in areas of montane forest heavily affected by deforestation.  相似文献   

3.
ABSTRACT

Ablabesmyia

is a speciose genus, with about 90 species distributed worldwide, 37 of which occurring in the Neotropical region. In Colombia, A. metica is the only species of the genus recorded so far, which was initially described with material collected in the Colombian Orinoquia and more recently recorded in the southeastern Brazil. In the present study, Ablabesmyia opita sp. n. from the Colombian Andes is described and illustrated based on adult males collected at the inter-andean valley of Magdalena river basin. In addition, an updated taxonomic key for Neotropical species and a map of Ablabesmyia records in Colombia are provided. The male of the new species is similar to that of A. laurindoi but can be easily distinguished by the coloration patterns of the legs, the shape of the sternapodeme and by the number of antepronotals.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:A9FD43D5-7018-4B3F-925B-E843B82D71E6  相似文献   

4.
Summary

Three new trechine species of the genus Pilosaphaenops Deuve & Tian, 2008, P. qianzhii n. sp. from cave Lubian Dong in Pingtang County, southern Guizhou Province, P. mengzhenae n. sp. and P. weiguofui n. sp. from cave Xia Dong in Nandan County, and cave Shenlong Gong in Huanjiang County respectively, northern Guangxi Zhuang Autonomous Region, are described and illustrated. A key to all known species of this genus is also provided.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:170C467F-5421-49AD-B1B1-091D8BD58B88  相似文献   

5.
We conducted a cytogenetic study of four hyline frog species (Dendropsophus elegans, D. microps, D. minutus and D. werneri) from southern Brazil. All species had 2n = 30 chromosomes, with interspecific and intraspecific variation in the numbers of metacentric, submetacentric, subtelocentric and telocentric chromosomes. C-banding and fluorochrome staining revealed conservative GC-rich heterochromatin localized in the pericentromeric regions of all species. The location of the nucleolus organizer regions, as confirmed by fluorescent in situ hybridization, differed between species. Telomeric probes detected sites that were restricted to the terminal regions of all chromosomes and no interstitial or centromeric signals were observed. Our study corroborates the generic synapomorphy of 2n = 30 chromosomes for Dendropsophus and adds data that may become useful for future taxonomic revisions and a broader understanding of chromosomal evolution among hylids.  相似文献   

6.

Aim

Invasive species are of increasing global concern. Nevertheless, the mechanisms driving further distribution after the initial establishment of non‐native species remain largely unresolved, especially in marine systems. Ocean currents can be a major driver governing range occupancy, but this has not been accounted for in most invasion ecology studies so far. We investigate how well initial establishment areas are interconnected to later occupancy regions to test for the potential role of ocean currents driving secondary spread dynamics in order to infer invasion corridors and the source–sink dynamics of a non‐native holoplanktonic biological probe species on a continental scale.

Location

Western Eurasia.

Time period

1980s–2016.

Major taxa studied

‘Comb jelly’ Mnemiopsis leidyi.

Methods

Based on 12,400 geo‐referenced occurrence data, we reconstruct the invasion history of M. leidyi in western Eurasia. We model ocean currents and calculate their stability to match the temporal and spatial spread dynamics with large‐scale connectivity patterns via ocean currents. Additionally, genetic markers are used to test the predicted connectivity between subpopulations.

Results

Ocean currents can explain secondary spread dynamics, matching observed range expansions and the timing of first occurrence of our holoplanktonic non‐native biological probe species, leading to invasion corridors in western Eurasia. In northern Europe, regional extinctions after cold winters were followed by rapid recolonizations at a speed of up to 2,000 km per season. Source areas hosting year‐round populations in highly interconnected regions can re‐seed genotypes over large distances after local extinctions.

Main conclusions

Although the release of ballast water from container ships may contribute to the dispersal of non‐native species, our results highlight the importance of ocean currents driving secondary spread dynamics. Highly interconnected areas hosting invasive species are crucial for secondary spread dynamics on a continental scale. Invasion risk assessments should consider large‐scale connectivity patterns and the potential source regions of non‐native marine species.
  相似文献   

7.
Abstract

Context

Acrylamide (ACR) is now a risk for general public health. Argan oil (AO) is harvested from the fruits of Argania spinosa and its rich source of antioxidant and phenolic compounds.  相似文献   

8.

Background  

Two common southern African mice species, Mastomys coucha and M. natalensis, are widely distributed throughout the subregion and overlap in many areas. They also share a high degree of morphological similarity, making them impossible to distinguish in the field at present. These multimammate mice are documented carriers of serious disease vectors causing Lassa fever, plague and encephalomyocarditis, which coupled to their cohabitation with humans in many areas, could pose a significant health risk. A preliminary study reported the presence of isozyme markers at three loci (GPI-2, PT-2, -3) in one population each of M. coucha and M. natalensis. Two additional populations (from the Vaal Dam and Richards Bay) were sampled to determine the reliability of these markers, and to seek additional genetic markers.  相似文献   

9.
  1. Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae) is a forest pest that damages a wide range of trees in areas where it has recently been introduced, demanding a proactive evaluation of its possible future distribution.
  2. This study aimed to project the potential distribution of A. glabripennis using species distribution modelling and constructed an ensemble map for evaluating global risk areas.
  3. We used CLIMEX and MaxEnt to evaluate the potential distribution of A. glabripennis as a function of current and future climates.
  4. The results showed that the models predicted a high probability of A. glabripennis distribution where this species is currently found, and the suitable climate was shifted northward due to climate change.
  5. The projected area differed between the models because of different modelling algorithm and climate change scenario; thus, an ensemble map projecting the consensus areas from two models was constructed to identify the risk areas that corresponded to the eastern United States, Europe, and native countries, Korea and China, and nearby Japan.
  6. From the perspective of ensemble modelling for evaluating species distributions with reduced uncertainties, this study will enhance the model reliability for defining areas at risk of A. glabripennis occurrence.
  相似文献   

10.
The new species, Matayba obovata (Sapindaceae), from southern and southeastern Brazil is described, illustrated, and contrasted to its putatively closest relatives. Palynological characters are also described. The new species belongs to sect. Matayba. A key to identify M. obovata and related species in the Atlantic Forest is included.  相似文献   

11.
Lutzomyia longipalpis and Lutzomyia cruzi are the main sandflies species involved in the transmission of Leishmania infantum protozoan in Brazil. The morphological characteristics can be used for species identification of males specimens, while females are indistinguishable. Although, sandflies identification is essential to understand vectorial capacity, and susceptibility to infectious agents or insecticides, there is a lack of new strategies for specimen identification. In this study, Fourier transform infrared photoacoustic spectroscopy combined with multivariate analysis identified intraspecific differences between Lutzomyia populations. Successfully group clustering was achieved by principal component analysis. The main differences observed can be related to the protein content of the specimens. A classification with 100% accuracy was obtained using machine learning approach, allowing the identification of sandflies specimens.  相似文献   

12.
13.

Premise

The interaction between ecological and evolutionary processes has been recognized as an important factor shaping the evolutionary history of species. Some authors have proposed different ecological and evolutionary hypotheses concerning the relationships between plants and their pollinators; a special case is the interaction and suspected coevolution among Agave spp. and their main pollinators, the Leptonycteris bats. Agave spp. have, in general, a pollination syndrome compatible with chiropterophily including floral shape and size, nocturnal nectar production, and nectar quality and sugar concentration. Our goal was to analyze the interaction Agave–Leptonycteris and its dynamics during three different climate scenarios.

Methods

We modeled the Agave–Leptonycteris interaction in its spatial and temporal components during the Pleistocene using Ecological Niche Models (ENMs) and three climate scenarios: Current, Last Glacial Maximum (LGM), and Last InterGlacial (LIG). Furthermore, we analyzed the geographic correlation between 96 Agave spp. and two of the Mexican Tequila bats, genus Leptonycteris.

Results

We found that Leptonycteris spp. interact with different Agave spp. over their migratory routes. We propose an interaction refuge in Metztitlán and Tehuacán-Cuicatlán areas, where Agave- Leptonycteris interaction has probably remained active. During the nonmigratory season, both bat species consume nectar of almost the same Agave spp., suggesting the possibility of a diffuse coevolution among Agave and Leptonycteris bats.

Conclusions

We propose that in the areas related to migratory bat movements, each bat species interacts with different Agave spp., whereas in the areas occupied by nonmigrant individuals, both bat species consume nectar of almost the same Agave taxa.
  相似文献   

14.
ABSTRACT

A new species of the spider genus Cuacuba from Brazil, C. ribeira sp. nov. is described and illustrated based on eighty-six specimens collected from caves in the Vale do Ribeira region, in the states of São Paulo and Paraná. This species is recognized by the hook-shaped median apophysis on the male palp, and females by having invaginations on the sides of the median posterior edge of the epigynal plate. Cuacuba ribeira sp. nov. is the third species recorded for the genus, and like the other two, also comes from Brazilian caves.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:44036D6B-CA3F-4C15-BBA3-3E5FE81FB299  相似文献   

15.
ABSTRACT

Euathlus

Ausserer, 1875 is a South American genus of spiders of the family Theraphosidae known from Chile and Argentina. Three new species from Argentina: Euathlus mauryi sp. n. (from San Juan province), Euathlus grismadoi sp. n. (from La Rioja province), and Euathlus pampa sp. n. (from Salta province) are described here. New records of the previous species Euathlus diamante and Euathlus tenebrarum are contributed. The distribution of these new species expands the geographical distribution of the genus along the Andean hills, with Salta province as the northernmost record of the genus. A key is provided for identification of Euathlus species as well as a map with all the records in Argentina.  相似文献   

16.
Seven new species ofMascagnia are described:M. tomentosa from southern Mexico and Central America;M. arenicola from the Guianas;M. riparia, M. tucuruensis, andM. velutina from Brazil;M. boliviana from Bolivia; andM. australis from Argentina and Paraguay. These novelties were previously included in the “M. sepium-complex,” an omniumgatherum comprising superficially similar yellow-flowered taxa.  相似文献   

17.
Mitracarpus longicalyx is here described and illustrated from sandy areas of the caatingas of northeastern Brazil. The new species is similar toM. hirtus andM. megapotamicus.  相似文献   

18.

Background

Paracoccidioidomycosis is a systemic mycosis caused by the dimorphic fungus Paracoccidioides brasiliensis. It is the principal systemic mycosis in Brazil, with higher incidence rates in the southern, southeastern, and midwestern regions. It primarily involves the lungs, but head and neck manifestations are common, and differential diagnosis with granulomatous and neoplastic diseases should therefore be considered.

Methods

We conducted a retrospective analysis of medical records of paracoccidioidomycosis cases with head and neck manifestations in southern Brazil over a 10-year period, from 1998 to 2008.

Results

A total of 36 cases of paracoccidioidomycosis were confirmed by histopathological examination, fungal investigation, or culture. Most cases consisted of men with smoking and/or chronic drinking habits and with poor hygiene and nutrition.

Conclusions

Paracoccidioidomycosis is endemic to southern Brazil. Most cases with mucocutaneous manifestations affect the head and neck region. Given that risk factors and clinical manifestations are similar to those of head and neck carcinomas, a differential diagnosis has to be done.  相似文献   

19.
  1. Leucoptera coffeella is one of the main coffee pests in the Neotropical region and particularly important in crops cultivated under full sun, as in Brazil. The intensive use of insecticides in the last two decades, including molecules of recent use such as chlorantranilprole, has not been successful in suppressing this pest species.
  2. Thus, study aimed to detect insecticide resistance and determine the levels of resistance to commercial formulations of the insecticides chlorantraniliprole, chlorpyrifos and thiamethoxam in populations of L. coffeella from Arabica coffee fields in western and the highlands of the state Bahia (Brazil). Furthermore, as the expression of insecticide toxicity varies with the length of exposure and the compound concentration, what is frequently neglected, these two variables were considered while determining the levels of resistance in nine populations.
  3. Moderate levels of resistance were detected to chlorantranilprole in two populations, whereas the others exhibited low levels of resistance. All populations were resistant to thiamethoxam ranging from low to moderate levels. Low levels of resistance to chlorpyrifos were detected in all populations from western, but none from highlands region.
  4. The western presents a more concerning scenario of insecticide resistance the L. coffeella, but the phenomenon requires attention in both regions.
  相似文献   

20.

Premise

Alismataceae, a sub-cosmopolitan family with ca. 17 genera and 113 species, is a large group of aquatic plants. Compression/impressions and bioinclusions of reproductive parts in amber support the documentation of the lineage in low-latitude North America. In Mexico, fossil aquatic plants have been infrequently documented. The new reproductive structures exhibit characteristics of Alismataceae, whose fossil record is mainly documented in the northern hemisphere through of fruits and seeds.

Methods

We described and compared 150 samples of reproductive structures preserved as impressions/compressions from the Oligocene Los Ahuehuetes locality in the state of Puebla, and two bioinclusions from the Miocene amber of Simojovel de Allende in the state of Chiapas, Mexico with extinct and extant taxa. Using a parsimony analysis based on 29 floral characters of 17 extant genera of the Alismataceae, we evaluated the relationship between the fossil material and potential living relatives.

Results

We discovered a new genus Nichima based on a perfect, actinomorphic flower with an expanded receptacle, three persistent sepals with multiple vasculatures, delicate and caducous petals, six stamens, and a gynoecium composed of three to more superior carpels, maturing into achenes. These characteristics resemble flowers of Alismataceae. Nichima represents an extinct member of the family, with two new species described here, Nichima magalloniae L. Hern., Cevallos-Ferriz et Hernández-Damián sp. nov. and Nichima gonzalez-medranoi L. Hern., Cevallos-Ferriz et Hernández-Damián, sp. nov. Their phylogenetic position suggests affinity with a clade that includes Baldiella, Echinodorus, and Alisma.

Conclusions

Reproductive structures from the Cenozoic of Mexico support the identification of a new extinct genus, Nichima, evidencing the extensive history of Alismataceae in North America's low latitudes and suggesting a southern extension of the boreotropical flora.
  相似文献   

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