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1.
Although the high diversity of neotropical plants is often associated with rain forests, another important location is open vegetation at mountain tops. In the present study, we investigated the phytogeographic patterns of the Espinhaço Range, in eastern Brazil, a region characterized by campos rupestres and marked by high levels of plant richness and endemism. Based on the occurrence of Asclepiadoideae (Apocynaceae) in a grid of 0.5º × 0.5º cells, we conducted cluster analyses and parsimony analysis of endemicity (PAE). We also calculated indexes of diversity and endemism and examined the distribution of palaeo- and neo-endemics. According to our data, the topographic gap between the Espinhaço Range of Minas Gerais and Bahia seems to be an important constraint for the dispersion of endemics, and the floristic similarity between northern Minas Gerais and Bahia is a result of species with broad distribution. Based on the seven areas of endemism that emerged from PAE, we defined five principal centres of endemism in the Espinhaço Range, including the region comprising Serra do Cipó and the Diamantina Plateau, in Minas Gerais, as the major Asclepiadoideae cradle, and Chapada Diamantina, in Bahia, as an Asclepiadoideae museum.  相似文献   

2.
The new species Sauvagesia lagevianae is described, illustrated, and discussed. This species is morphologically similar to S. glandulosa, but can be easily distinguished by its unique umbellate inflorescence arising from a distinct peduncle on the branch apex. Other diagnostic characters to identify S. lagevianae are the nodding, campanulate corollas, bi-apiculate anthers, and the small and strongly imbricate leaves with fewer and ascending secondary veins. The new species is only known from two nearby localities of “campo rupestre” vegetation in the Espinhaço range of Minas Gerais, Brazil.  相似文献   

3.
The Southern Espinha?o Range consists of large areas covered by quartzitic or metaliferous tropical altitudinal fields. The Espinha?o Range ecosystems are endangered by anthropic high impacts, particularly due to mining and urbanization. We conducted a one-year inventory of the bee flora and fauna at the quartzitic Ouro Branco Mountains and a two-year survey of the metaliferous Ouro Preto fields. The samples were collected twice a month, from 8:00 am to 5:00 pm. The bees (677) belonged to 91 species, five families. The family Apidae was the richest and most abundant, followed by the Halictidae and Megachilidae. The bees visited 46 flowering plant species; the most visited plants were the Asteraceae (n = 220), the Malpighiaceae (n = 95), the Melastomataceae (n = 94), the Fabaceae (n = 78), and the Solanaceae (n = 63). Diversity was higher in Ouro Branco (H = 1.47) than in Ouro Preto (H = 1.17). The low richness and abundance of bees in our research site when compared to other Brazilian "Cerrado" areas can be due to the high altitude, low temperature, and low availability of flowers we found. "Canga" and rupestrian areas house fauna and flora species that are rare and threatened by extinction. The southern Espinha?o areas can, therefore, be given the status of permanent biodiversity preservation area.  相似文献   

4.
A study of the phlebotomine sand fly fauna was carried out in the Rio Preto State Park (Minas Gerais, Brazil) aiming to associate the presence of vector species with the risk of leishmaniasis transmission in that region. Sand flies were captured using HP light traps for four months from January to October 2013. The traps were exposed continuously for 40 h each month, in nine fixed sites. A total of 3129 sand flies were captured, belonging to 19 species. Lutzomyia evandroi (Costa Lima & Antunes 1936) was the predominant species (76.48%). The distribution of the phlebotomine sand flies and climatic factors (temperature, humidity, and rainfall) was evaluated. The summer was the season with higher occurrence of insects captured (82.4%). The presence of cutaneous and visceral vector species in park areas requires attention and regular monitoring of sand fly fauna in this conservation area to ensure the well-being of visitors and the regional ecotourism.  相似文献   

5.
This study investigated the orchid-bee community in a conservation gradient of the high-altitude rocky fields in the state of Minas Gerais, Brazil. Sampling was performed at two sites with different anthropic influences: a disturbed area (DA), with exotic plant species, and a preserved area (PA). From September 2009 through February 2011, males of euglossine bees were sampled using aromatic bait-traps. We collected a total of 819 specimens belonging to 11 species and three genera: Euglossa Latreille, Eulaema Lepeletier, and Eufriesea Cockerell. Despite the proximity of DA and PA (about 1.2 km), differences in orchid-bee abundance and richness were observed. Higher abundance was observed in the PA (n?=?485) compared with the DA (n?=?334). Eight species were common to both sites, and only the DA showed exclusive species. The DA showed higher diversity and higher estimated species richness. Euglossa leucotricha Rebêlo & Moure was the most abundant species at both sites followed by Euglossa melanotricha Moure. Higher abundance and richness were found in the warm rainy season. This study contributes to the knowledge of the orchid-bee fauna in the rocky fields and suggests that the greater resource availability in the DA was responsible for the higher orchid-bee diversity.  相似文献   

6.
7.
The protection of areas that shelter high evolutionary diversity represented by geographically and phylogenetically isolated lineages is becoming an important conservation strategy. Nevertheless, the spatial distribution of this component of biodiversity is still unknown for most groups, which limits its application for selecting priority areas to conserve. In the present study, we reconstructed the phylogeny of Minaria (Apocynaceae) based on plastid (trnH-psbA, rps16, trnS-trnG and trnD-trnT) and nuclear (ITS and ETS) DNA markers and 34 morphological characters, and analysed the geographic distribution of the phylogenetic diversity (PD) and endemism (PE) in this genus. Minaria includes 21 species that are highly concentrated in the Espinhaço Range, in eastern Brazil, most of which (~75%) are narrowly distributed. The spatial analyses of PD and PE of Minaria indicate four evolutionary relevant areas in this region. The Serra do Cipó and the Diamantina Plateau contain 10 endemic species and present the highest levels of PD. However, the two other areas also deserve special attention. Rio de Contas has high levels of PE, because of two endemic sister species that represent a phylogenetically isolated lineage and the Southern Espinhaço Range houses the most critically endangered species of the genus. Most endemic species of Minaria occur in vegetation islands on rocky outcrops (campos rupestres). These low-fuel areas are less susceptible to fire, suggesting that the Espinhaço Range has served as a historical refuge for fire-sensitive lineages. Our results suggest that conservation units in the Espinhaço Range cover a great proportion of the evolutionary diversity of Minaria and that fire management is probably an important strategy to preserve this endemic biodiversity.  相似文献   

8.
We describe and illustrate the new species Comanthera brunnea (Eriocaulaceae: Paepalanthoideae). This species is endemic to the sandy fields of the campos rupestres of the northeastern Espinhaço range in Minas Gerais, Brazil. We compare it with Comanthera suberosa, the morphologically most similar species, and with C. brasiliana, which also has similar features. The morphological variation, habitat, geographic distribution, and conservation status of this new species are discussed.  相似文献   

9.
A new species of Microlicia (Melastomataceae) from Diamantina, Minas Gerais, Brazil is described and illustrated and a conservation assessment based on IUCN criteria is given.  相似文献   

10.
Three Pseudocercospora species were found associated with leaf spots on five different members of the family Piperaceae in a stretch of Atlantic rain forest in the municipality of Viçosa, Minas Gerais, Brazil. Pseudocercospora piperis is newly recorded on Piper crassinervium and Piper mollicomum. It was also found in association with Pothomorphe umbellata, which is already known to be a host. Pseudocercospora piperis-arborei sp. nov. and Pseudocercospora piperis-gigantifolii sp. nov. were recorded on Piper arboreum and Piper gigantifolium, respectively. These three species are fully described and illustrated in the present work.  相似文献   

11.
Coelomera lanio (Coleoptera: Chrysomelidae) is the most important defoliator of Cecropia trees. Natural enemies of C. lanio collected in the region of Vi?osa, State of Minas Gerais, Brazil were identified on field observations in a forest fragment and on laboratory analyses. Individuals of C. lanio were not found on Cecropia pachystachya trees colonized by Azteca mülleri (Hymenoptera: Formicidae). The majority of the egg masses of C. lanio collected in the field were found to be parasitised by a species of the family Eulophidae (Hymenoptera), while larvae of this pest were attacked by a parasitoid of the family Tachinidae (Diptera). Individuals of Oplomus catena (Heteroptera: Pentatomidae) were observed preying on C. lanio larvae. The fungus Beauveria bassiana was found growing on larvae, pupae and adults of C. lanio while the fungus Metarhizium anisopliae only affected pupae of this insect in laboratory conditions.  相似文献   

12.
We evaluated the presence and distribution of Trypanosoma cruzi DNA in a mummy presenting with megacolon that was dated as approximately 560 +/- 40 years old. The mummy was from the Perua?u Valley in the state of Minas Gerais, Brazil. All samples were positive for T. cruzi minicircle DNA, demonstrating the presence and broad dissemination of the parasite in this body. From one sample, a mini-exon gene fragment was recovered and characterized by sequencing and was found to belong to the T. cruzi I genotype. This finding suggests that T. cruzi I infected humans during the pre-Columbian times and that, in addition to T. cruzi infection, Chagas disease in Brazil most likely preceded European colonization.  相似文献   

13.
During floristic work on Espinha?o Range-Brazil, we recognised five Habranthus species, plus two new species, described and illustrated here: Habranthus botumirimensis R. S. Oliveira is similar to H. datensis Ravenna as both have a paraperigone of fimbrae, but is distinguished by possessing narrower leaves (c. 3 mm wide), erect stigma lobes, tepals with narrower bases, and by the arrangement of papillae in a longitudinal strip on the outer tepals; Habranthus lucidus R. S. Oliveira closely resembles H. itaobinus Ravenna, having staminal filaments in two lengths with the style not exceeding the longest filaments, but is distinguished by possessing funnelform and more distinctly zygomorphic flowers, oblanceolate tepals, darker nerves, and outer tepals with obtuse apices. An identification key to Habranthus species from the Espinha?o Range is provided.  相似文献   

14.
Encholirium is a Brazilian genus of Bromeliaceae that occurs exclusively in rocky landscapes. This work aimed to generate basic information for the conservation of three Encholirium species that are endemic to the rocky mountains of Cadeia do Espinhaço, employing population genetic analyses. E. pedicellatum and E. biflorum have only one very small population each, both occurring in unprotected, private land sites, being critically endangered. E. subsecundum is more widespread, and some of its populations dwell in protected areas. Five Random Amplified Polymorphic DNA (RAPD) primers generated approximately 60 polymorphic bands for each species. This technique demonstrated the presence of a single RAPD profile for every individual sampled (except for one clone found in E. biflorum). High levels of genetic variability were not expected, due to the clonal habit of the plants and small size of the populations. Populations of E. biflorum and E. pedicellatum presented, respectively, 16.06% (Φ st  = 0.16, p<0.001) and 8.44% (Φ st  = 0.08, p<0.001) of the total genetic diversity attributable to genetic differences among groups within the populations. In E. subsecundum, 14.52% (Φ st  = 0.15, p<0.001) of the total genetic diversity was found among populations. Estimates of the Shannon’s Diversity Index provided similar results. These results are valuable for the development of conservation strategies.  相似文献   

15.
Three new species of Mimosa are described: M. (sect. Batocaulon) epitropica Barneby & León de la Luz from Mexico (Baja California Sur); and two from planaltine Brazil, M. (sect. Habbasia) bispiculata Barneby and M. (sect. Mimosa) demissa Barneby. The affinity of each is discussed, and all are illustrated.  相似文献   

16.
17.
We surveyed the phlebotomine fauna in the Parque Nacional Cavernas do Perua?u, Minas Gerais, Brazil, aiming to associate the presence of vector with the risk of leishmaniasis transmission. Field captures were performed with CDC light traps between February and March 2003. A total of 436 sand flies were captured, belonging to 14 species. The predominant species (28.7%) was Lutzomyia ischnacantha Martins, Souza e Falc?o, followed by L. renei (27,06%) and L. cavernicola (13,07%). The finding of L. intermedia, a species that is incriminated as vector of cutaneous leishmaniasis, has to be taken into account.  相似文献   

18.
Taxonomic markers (head structure morphometry, isoenzymes and randon amplified polymorphism of DNA - RAPD) were used to understand the population dynamics of Triatoma vitticeps, predominant triatomine species in Itanhomi district, using samples obtained from domestic, peridomiciliary and sylvatic habitats. Morphometric analysis revealed sexual dimorphism within the three samples although specimens could not be separated according to the habitat in which they were captured. Forty-two bands were analyzed from RAPD profiles generated using four primers. A dendrogram constructed from Dice's similarity coefficient values showed that migration of the insects between the habitats has occurred, without structuring of populations. Moreover, the dendrogram obtained from the genetic distance values showed an important gene flow between the sylvatic and domestic habitats. No polymorphism was found in the electrophoretic mobility of proteins for the ten enzymes studied. Our results revealed movement of triatomines between the three habitats, suggesting that the presence of T. vitticeps in houses should not be ignored. As invasion of houses by sylvatic insects is frequent and the natural infection indices of this species are among the highest known, epidemiological vigilance studies may reveal possible changes in T. vitticeps behaviour which could present future risks to public health.  相似文献   

19.
We describe the larval stage of Simulium cuasiexiguum Shelley, Luna Dias, Maia-Herzog & Lowry and Simulium obesum Vulcano and provide new distribution records of four black fly species in the State of S?o Paulo (Simulium cuasiexiguum, Simulium metallicum s.l. Bellardi, Simulium stellatum Gil Azevedo, Figuer6 & Maia-Herzog and Simulium oyapockense s.l. Floch & Abonnenc) and three species in the State of Minas Gerais (Simulium duodenicornium Pepinelli, Hamada & Trivinho-Strixino, Simulium obesum and Lutzsimulium pernigrum Lutz).  相似文献   

20.
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