950 resultados para Cerrado stricto sensu
Resumo:
No Brasil, a Família Didelphidae é composta por 54 espécies com ampla distribuição por diferentes habitats e um padrão de consumo alimentar que pode variar desde espécies mais frugívoras até as mais insetívoras/carnívoras. O objetivo deste estudo foi avaliar a relação entre a dieta de sete espécies de didelfídeos (Caluromys philander, Didelphis albiventris, Gracilinanus agilis, G. microtarsus, Marmosa (Micoureus) paraguayana, Marmosops incanus e Metachirus nudicaudatus) e a seleção de recursos alimentares (artrópodes e frutos) disponíveis. O estudo foi realizado entre novembro de 2009 e outubro de 2011, em uma área de mata ciliar de cerrado no Parque Estadual do Rio Preto, Minas Gerais, Brasil. Artrópodes, frutos, flores e vertebrados foram consumidos em diferentes proporções pelas espécies estudadas. Flores e vertebrados foram consumidos preferencialmente na estação seca e a diversidade da dieta de todas as espécies foi maior durante a estação chuvosa. Nem todos os recursos (artrópodes e frutos) foram consumidos de acordo com sua disponibilidade na área de estudo. Apesar de abundante, Hymenoptera (Formicidade) foi rejeitado por todas as espécies, sendo consumido abaixo de sua disponibilidade local. Os didelfídeos selecionaram frutos de Melastomataceae (Clidemia urceolata e Miconia spp.) e rejeitaram frutos de Rubiaceae, um recurso altamente abundante na área de estudo. Os resultados sugerem que o frequente consumo de um item alimentar pode estar associado tanto com a preferência (seleção) por parte do consumidor, bem como com a disponibilidade local do recurso. A maior parte das sementes, que permaneceram intactas após passagem pelo trato digestório dos animais, não apresentou diferenças significativas em suas taxas de germinação quando comparadas com as sementes do grupo controle e o tempo médio de dormência das sementes consumidas pelos marsupiais variou entre 30 (Cipocereus minensis) e 175 dias (Cordiera sessilis). Gracilinanus agilis e G. microtarsus, que ocorrem em simpatria na área de estudo, apesar de apresentarem uma alta sobreposição de nicho apresentaram diferenças no uso do habitat e na diversidade da dieta.
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The Caranx hippos species complex comprises three extant species: crevalle jack (Caranx hippos) (Linnaeus, 1766) from both the western and eastern Atlantic oceans; Pacific crevalle jack (Caranx caninus) Günther, 1868 from the eastern Pacific Ocean; and longfin crevalle jack (Caranx fischeri) new species, from the eastern Atlantic, including the Mediterranean Sea and Ascension Island. Adults of all three species are superficially similar with a black blotch on the lower half of the pectoral fin, a black spot on the upper margin of opercle, one or two pairs of enlarged symphyseal canines on the lower jaw, and a similar pattern of breast squamation. Each species has a different pattern of hyperostotic bone development and anal-fin color. The two sympatric eastern Atlantic species also differ from each other in number of dorsal-and anal-fin rays, and in large adults of C. fischeri the lobes of these fins are longer and the body is deeper. Caranx hippos from opposite sides of the Atlantic are virtually indistinguishable externally but differ consistently in the expression of hyperostosis of the first dorsalfin pterygiophore. The fossil species Caranx carangopsis Steindachner 1859 appears to have been based on composite material of Trachurus sp. and a fourth species of the Caranx hippos complex. Patterns of hyperostotic bone development are compared in the nine (of 15 total) species of Caranx sensu stricto that exhibit hyperostosis.
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Genetic variation of Contracaecum ogmorhini (sensu lato) populations from different otariid seals of the northern and southern hemisphere was studied on the basis of 18 enzyme loci as well as preliminary sequence analysis of the mitochondrial cyt b gene (260 bp). Samples were collected from Zalophus californianus in the boreal region and from Arctocephalus pusillus pusillus, A. pusillus doriferus and A. australis from the austral region. Marked genetic heterogeneity was found between C. ogmorhini (sensu lato) samples from the boreal and austral region, respectively. Two loci (Mdh-2 and NADHdh) showed fixed differences and a further three loci (Iddh, Mdh-1 and 6Pgdh) were highly differentiated between boreal and austral samples. Their average genetic distance was DNei = 0.36 at isozyme level. At mitochondrial DNA level, an average proportion of nucleotide substitution of 3.7% was observed. These findings support the existence of two distinct sibling species, for which the names C. ogmorhini (sensu stricto) and C. margolisi n. sp., respectively, for the austral and boreal taxon, are proposed. A description for C. margolisi n. sp. is provided. No diagnostic morphological characters have so far been detected; on the other hand, two enzyme loci, Mdh-2 and NADHdh, fully diagnostic between the two species, can be used for the routine identification of males, females and larval stages. Mirounga leonina was found to host C. ogmorhini (s.s.) inmixed infections with C. osculatum (s.l.) (of which C. ogmorhini (s.l.) was in the past considered to be a synonym) and C. miroungae; no hybrid genotypes were found,confirming the reproductive isolation of these three anisakid species. The hosts and geographical range so far recorded for C. margolisi n. sp. and C. ogmorhini (s.s.) are given.
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The anuran tribe Paini, family Dicroglossidae, is known in this group only from Asia. The phylogenetic relationships and often the taxonomic recognition of species are controversial. In order to stabilize the classification, we used approximately 2100bp o
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Based on its characteristic oral apparatus, the ciliate subclass Peritrichia has long been recognized as a monophyletic assemblage composed of the orders Mobilida and Sessilida. Following the application of molecular methods, the monophyly of Peritrichia has recently been questioned. We investigated the phylogenetic relationships of the peritrichous ciliates based on four further complete small subunit ribosomal RNA sequences of mobilids, namely Urceolaria urechi, Trichodina meretricis, Trichodina sinonovaculae, and Trichodina ruditapicis. In all phylogenetic trees, the mobilids never clustered with the sessilids, but instead formed a monophyletic assemblage related to the peniculines. By contrast, the sessilids formed a sister clade with the hymenostomes at a terminal position within the Oligohymenophorea. We therefore formally separate the mobilids from the sessilids (Peritrichia sensu stricto) and establish a new subclass, Mobilia Kahl, 1933, which contains the order Mobilida Kahl, 1933. We argue that the oral apparatus in the mobilians and sessilid peritrichs is a homoplasy, probably due to convergent evolution driven by their similar life-styles and feeding strategies. Morphologically, the mobilians are distinguished from all other oligohymenophoreans by the presence of the adhesive disc, this character being a synapomorphy for the Mobilia.
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The phylogenetic relationships within the family Penaeidae are examined based on mitochondrial 16S rRNA gene sequence analysis of 30 species from 20 genera. The analysis generally supports the three- tribe scheme proposed by Burkenroad ( 1983) but it is not consistent with the five- group classification of Kubo ( 1949). Three clades are resolved: ( Penaeus sensu stricto + Fenneropenaeus + Litopenaeus + Farfantepenaeus + Marsupenaeus + Melicertus + Funchalia + Heteropenaeus), ( Metapenaeus + Parapenaeopsis + Xiphopenaeus + Rimapenaeus + Megokris + Trachysalambria) and ( Metapenaeopsis + Penaeopsis + Parapenaeus), corresponding to the Penaeini, Trachypenaeini and Parapenaeini respectively, while the affinities of Atypopenaeus and Trachypenaeopsis are obscure. The molecular data support that Miyadiella represents the juvenile stage of Atypopenaeus. Within the Trachypenaeini, Trachypenaeus sensu lato is clearly paraphyletic, while the monophyly of Penaeus sensu lato in the Penaeini is questionable.
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1995年9月、2004年6月和8月在中国辽宁省宽甸县白石砬子自然保护区及周围森林采集木腐菌标本276号,经鉴定研究发现多孔菌84种,本文报道了这些多孔菌名录,并根据采样列出了每种的寄主,其中绝大多数种类为该保护区首次报道,34种为辽宁新记录种。Perenniporia medulla-panis sensu stricto为中国新记录种,根据中国的标本材料对其进行了详细描述。白石砬子自然保护区及周围地区的多孔菌主要是温带广布种。
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北半球针叶林最严重的森林病害是由广义的多年异担子菌(Heterobasidion annosum sensu lato)引起的干基白色腐朽病,但近年的研究表明多年异担子菌并不是单一的物种,目前在欧洲已分出3个独立的种,即原始多年异担子菌(Heterobasidion annosum sensu stricto)、小孔异担子菌(Heterobasidion parviporum)和冷杉异担子菌(Heterobasidi-on abietinum),它们生物学习性、形态结构,生态学,寄主范围和发生区域均有差异。应用大伏革菌Phlebiopsisgigantea对该类病害进行生物防治是较好的方法。将中国东北和西南(云南)的异担子菌单孢菌株与欧洲的三种异担子菌进行交配,结果表明中国东北和西南地区的异担子菌与原始多年异担子菌无性亲和反应,而与小孔异担子菌有性融合反应,因此中国东北和西南地区的异担子菌是小孔异担子菌,目前中国并不存在原始多年异担子菌。由于原始多年异担子菌和冷杉异担子菌均为严重的森林病原菌,应将其作为对外检疫对象。
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Two marine urostylid ciliates, Holosticha hamulata n. sp. and Holosticha heterofoissneri Hu and Song, 2001, were investigated using live observation and protargol impregnation. Both species were isolated from Korean intertidal sediments of the Yellow Sea. Holosticha hamulata measures about 150 x 25 pro in vivo, and is characterized by a tripartite body shape with a narrow head, an inflated trunk, and a tail that distally projects ventrally forming a hook-like structure. It is the characteristic body shape that distinguishes H. hamulata distinctly from congeners. Holosticha hamulata differs from H. heterofoissneri, possibly the nearest relative, also by the location of the contractile vacuole (ahead of mid-body versus near posterior body third) and the configuration of the macronucleus (on average, 33 scattered nodules assuming a Y-shape versus 17 nodules that may form a U shape). The average number of the macronuclear nodules is a pronounced feature showing great consistency in populations of each species. However, their arrangement is variable in H. heterofoissneri where the nodules are basically scattered or connected by fine fibers forming an elongate U-shape. The location of the contractile vacuole as a taxonomic feature is discussed and a dichotomous key to the species of Holosticha sensu stricto is provided.
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2009
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2006
Área de plantio direto e área plantada com sorgo no cerrado: existente alguma correlação entre elas?
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2007