15 resultados para PARKERI


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The external morphology of the nymph of Amblyomma geayi Neumann is described by optical and scanning electron microscopy. Unfed nymphs were obtained from an engorged A. geayi female, which had been collected on a sloth (Bradypus variegatus) from Belém municipality, State of Pará, northern Brazil, and was kept under laboratory conditions. With the present description, we propose a modification of a taxonomic key published in 2010 for the Amblyomma nymphs that occur in Brazil, through the inclusion of A. geayi. The nymph of A. geayi is morphologically very similar to the nymph of Amblyomma parkeri Fonseca and Aragão, with only slight morphological differences related to scutal surface and punctuations (more shagreened and less punctuated in A. geayi). These 2 nymphs differ from all other known Amblyomma nymphs from Brazil by the combination of auriculae present as small posterolateral rounded projections, eyes located at the level of the scutal midlength, and a rounded hypostome. These nymphal similarities as well the morphology of the adult stage corroborate previous studies that showed that A. geayi and A. parkeri are genetically closely related. Unpublished host records of the nymphs of both A. geayi and A. parkeri are provided. Established populations of A. geayi and A. parkeri seem to be geographically separated, since all confirmed records of A. geayi are from the northern half of South America (mainly the Amazonian region) and Central America, whereas all known records of A. parkeri are from the Atlantic rainforest biome in northeastern, southeastern, and southern Brazil. © 2013 Elsevier GmbH.

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The Gillbacker Sea Catfish is a valid species of ariid catfish from the northeastern coast of South America. There are many synonyms In the literature for the Gillbacker Sea Catfish and even recent classifications have used different scientific names. Examination of a wide range of sizes of Individuals from different localities and examination of types and original species descriptions of Silurus parkeri, Bagrus flavescens, B. emphysetus, Arius physacanthus, A. bonneti, A. clavispinosus, and A. despaxi has lead us to the conclusion that all these names refer to the Gillbacker Sea Catfish and the valid name for the species is Sciades parkeri. The species is distinguished from all other ariid species by the following combination of features: body coloration yellow; swim bladder divided Into three chambers, posterior chamber moderately sized; nuchal plate shield-shaped, usually larger than supraocciptal process; anterior notch of nuchal plate absent; head shield exposed and granulated In orbital and postorbital regions; lateral edge of accessory patches not emarginated or shallowly notched; fleshy furrow connecting posterior nares absent; and mesial gill rakers absent from first two gill arches. Striking intraspecific and/or ontogenetic variation In eye size, maxillary-barbel length, supraoccipital-process size, nuchal-plate size and shape, and dorsal-spine thickness contributed to the numerous synonyms and misidentifications for Sciades parkeri. Bagrus albicans, described from French Guiana, has at times been listed as a synonym of Sciades parkeri. Our examination of the holotype of B. albicans, however, led us to conclude that It is a synonym of Sciades proops.

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倭蛙属Nanorana和高山蛙属Altirana均为横断山高海拔地区物种,二属共计三种,即腹斑倭蛙N. ventripunctata、倭蛙N. pleskei和高山蛙A. parkeri。本文将判别分析用于数值分类,对此三种蛙的十六个外部形态指数进行了聚类分析,结果显示腹斑倭蛙与高山蛙有更大的相似性;另外,作者利用淀粉凝胶电泳分析了七种同工酶十二个位点的等位基因频率,通过UPGMA法聚类,发现倭蛙与高山蛙的亲源关系更近。两种方法都证明了高山蛙独立成属的可能性比较小。据此本文建义取消高山蛙搁属级阶元,将其并入委蛙属中。作者并从古地质、气候变迁的角度推测了此三种蛙的隔离机制:倭蛙与高山蛙的分化可能源于澜沧江两岸高山峡谷的有效隔离,而腹斑倭蛙同二者的分离则可能是横断山不均匀抬升及第四纪冰期所带来的结果。

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棘蛙族(Tribe Paini)隶两栖纲(Amphibia)、无尾目(Anura)、蛙科(Ranidae)、叉舌蛙亚科(Dicroglossinae),由棘蛙属(Paa)、倭蛙属(Nanorana) 和沙巴蛙属(Chaparana)构成(Dubois,1992)。由于特殊的形态特征和染色体核型,棘蛙族受到国内外学者的广泛重视和研究,但是到目前为止,棘蛙族的系统发育关系尚未明晰,族下属种的分类和归属问题还有待进一步研究和新的证据出现。本文通过光学显微镜、电子显微镜和石蜡切片对棘蛙族10 物种的精子和精巢进行研究,旨在了解棘蛙族精子的形态、量度、超微结构特征及不同季节精巢结构的变化规律,同时为棘蛙族的系统研究提供新的依据,也为棘蛙族濒危物种的保护和经济物种的繁殖提供基础资料。研究结果表明:棘蛙族各属物种精子的形态基本相似,精子整体呈线形,由头部、中片和尾部构成。精子头部呈长条状,顶体呈锥状,位于头部顶端并向前伸出,中片较长,尾部波动弯曲。棘蛙族各属物种精子量度差异较大,将各属物种精子头部、中片、尾部、头宽、尾宽的量度数据进行聚类分析,结果表明棘蛙族10 物种可分为三类:第一类包括棘侧蛙、合江棘蛙、小棘蛙、棘腹蛙和棘胸蛙,特点是精子较短,全长在72.6~103.35µm 之间;第二类包括倭蛙、高山倭蛙、腹斑倭蛙,特点是精子较长,全长在107.74~129.75µm 之间;第三类包括隆肛蛙和双团棘胸蛙,特点是精子最长,全长在145.89~165.84µm 之间。棘蛙族各属精子超微结构基本相似:精子头部由顶体、细胞核构成;中片由中心粒、线粒体构成;尾部由单根轴丝构成。精子顶体横切呈圆环状,细胞核电子密度高;线粒体为卵圆形,呈环状围绕轴丝排列,线粒体数目较多,约30层;尾部轴丝为典型的9+2结构,即由2根中央微管和9对外周微管组成。不同季节的倭蛙精巢结构变化表明倭蛙精巢每年只有一个生精周期,生精周期始于7 月,繁殖季节从5 月到6 月,生精高峰期为9 月;根据倭蛙不同季节精巢结构的变化,可将生精周期分为3 个阶段:第一阶段从7 月到9 月,为精子形成期;第二阶段从10 月到翌年4 月,为精子的贮存阶段,也即倭蛙的冬眠期;第三阶段从5 月到6 月,为精子的排放阶段,即倭蛙的繁殖期。不同季节的隆肛蛙精巢结构变化表明5 月为隆肛蛙的繁殖高峰期。根据棘蛙族各属精子的形态、量度和超微结构特征,结合已有的棘蛙族形态学、生态学、染色体核型及系统学研究成果,本文认为:1.基于精子数据对棘蛙族的划分和基于形态学及分子系统学数据对棘蛙族的划分均有相同之处,精子形态结构可为棘蛙族的系统研究提供新的证据。2. 棘蛙族各属精子的形态、量度及超微结构不仅与蛙科其他属种有明显差异,而且在无尾类中也较为特殊,精子学研究结果支持将棘蛙族从蛙科中分离出来,归隶于叉舌蛙科的叉舌蛙亚科的系统学修正。3. 精子的顶体、细胞核、中片的形态结构及量度可作为蛙科的分类指标。On the base of unique morphological and kyrotype characters, Dubois(1992)recognized three genera Paa, Narnorana, Chaparana as tribe Paini, which is amember of Dicroglossinae, Ranidae. In present study, the sperm shape, size andultrastructure of 10 paini species were investigated through the light and electronmicroscope, and testis structure of N. pleskei and F. quadrana was also studied. Wesuppose this study could offer some spermatological evidence to phylogeny andreproduction study of tribe Paini. The results were as follows:The sperm shape of tribe paini is homologically similar, the spermatozoa arefiliform, composed of elongate head, long mid-piece and waved tail. The acrosome isapically associated with the nucleus and extend anteriorly.The sperm length of tribe paini differ remarkably among genera. Cluster for thelength of sperm head, mid-piece, tail, total length, head-width, tail-width of ten painifrogs indicated the 10 species could be separated into three groups: GroupⅠcontainsP. shini, P. robertingeri, P. spinosa, P. exilispinosa, P. boulengeri, the spermatozoa ischaracterized with short in total length, ranging from 72.6µm to 103.35µm; GroupⅡcontains N. pleskei, N. parkeri, N. ventripunctata, the spermatozoa ischaracterized with relatively long in total length, ranging from 107.74µm to129.75µm; Group Ⅲ contains F. quadrana and P. yunnanensis, the spermatozoa is characterized with longest in total length, ranging from 145.89µm to 165.84µm. thethree groups based on spermatological data is partially match the classification basedon morphological and molecular data.The ultrastructure of spermatozoa in tribe paini is also basic similar, includingacrosome vescile, nuleus of the head proper, centriole, mitochondriol of themid-pieces, axoneme of the tail. The acrosome vescle is circle in TEM transversesection, the density of nucleus is high; The mitochondrions is oval, surrounding theaxial filament with about 30 layers of mitochondria; The axoneme has the typical 9+2pattern of microtubules.The seasonal changes in testis of N. pleskei indicates it has only onespermatogenesis circle, which begin in July, the reproduction season is from May toJune, the spermatogenesis is active in September. On the base of seasonal changes intestis, the spermatogenesis circle can be separated into three stages: In stageⅠfromJuly to September, spermatids are formed; In stage Ⅱ from October to April next year,the spermatozoa are stored in testis,which is the hibernated period; In stage Ⅲ fromMay to June, mature spermatozoa were released from the testis, which is thereproduction season of N. pleskei. As to F. quadrana, reproduction is active in May.With the previous study of morphology, ecology, karyotypes and phylogenyresearch of tribe Paini, the spermatological data in present study suggests:1. The spermatological classification of tribe paini is partially consistant with themorphological and molecular classification respectively.2.The sperm morphology and ultrustructure of tribe paini is unique not only inthe family Ranida but also in Anura, which suggest the tribe paini is monophyletic andmight be transfered from the family Ranida to the family Dicroglossidae based onmolecular evidence.3. The acrosome, nuleus, shape, length and ultrastructure of mid-piece can beused as an alternative taxonomic character in Anura.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Pertencente a ordem dos Siluriformes, a família Ariidae compreende os bagres marinhos e estuarinos os quais distribuem-se pelas costas de todos os continentes, habitando áreas costeiras de região tropical e subtropical, onde vivem em águas de pouca profundidade, com fundo arenoso ou lodoso. No estuário Amazônico, no estado do Pará, encontram-se 7 espécies pertencentes ao gênero Anus (A. couma, A. parkeri, A. rugispinis, A. quadriscutis, A. grandicassis, A. phrygiatus e A. proops). O objetivo deste estudo é identificar os hábitos alimentares, sobreposição alimentar e espacial, distribuição espacial e sazonal das espécies de Anus (Siluriformes, Ariidae) do Estuário Amazônico. As coletas foram realizadas durante o período de agosto a outubro de 1996, de fevereiro a abril e agosto a outubro de 1997. Os indivíduos foram capturados com rede de fundo sem porta da frota piramutabeira do estuário Amazônico. Existem dois grupos de espécies do gênero Anus: as espécies que se alimentam de crustáceos (A. rugispinis, A. quadriscutis, A. grandicassis, A. phrygiatus e A. proops) e as espécies que se alimentam de peixes (A. couma, A. parken). Com relação a sobreposição alimentar todas as espécies apresentam um certo grau sobreposição alimentar assim como a sobreposição espacial. A. couma e A. phrygiatus estão mais abundantes nos estratos de profundidade entre 5-10 m e A. rugispinis, A quadriscutis, A. grandicassis, A. parkeri e A. proops nos estrato de 10-20 m. A. phrygiatus é a única espécie que apresenta maior abundância durante o inverno e as demais espécies aparecem tanto no verão como no inverno

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Objetivo deste trabalho foi identificar a fauna parasitária, em especial os cestóides da ordem Trypanorhyncha, que acometem peixes de valor comercial capturados no litoral amazônico e avaliar os possíveis impactos na produção pesqueira industrial. Foram examinados 328 exemplares de cinco espécies de peixes: Cynoscion acoupa, Macrodon ancylodon, Plagioscion squanosissimus, Centropumus undecimalis, Arius Parkeri. Foi feita a mensuração do seu comprimento total e pesagem dos peixes, na filetagem examinou as regiões corporais, musculatura e serosa. Os blastocistos de Trypanorhyncha encontrados foram removidos e encaminhados para Laboratório Carlos Azevedo. Todas as espécies pesquisadas estavam parasitadas por Trypanorhyncha, totalizando 283 (73,78%) exemplares parasitados. A espécie Callitetrarhynchus gracilis apresentou maior prevalência parasitária. Poecilancistrium aryophyllum foi a que mais parasitou as espécies de peixes estudadas, seguida da Pterobothrium crassicolle e as Pterobothrium heteracanthum e Callitetrarhynchus speciosum, parasitaram Cynoscion acoupa e Arius Parkeri, respectivamente. As regiões da musculatura abdominal e dorso-lateral foram as mais acometidas.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Tick-borne relapsing fever in western North America is a zoonosis caused by spirochetes in the genus Borrelia that are transmitted by argasid ticks of the genus Ornithodoros (1). Human disease occurs in many focal areas and is associated with infections of Borrelia hermsii, B. turicatae, and possibly B. parkeri (2,3). Although the ecologic parameters that maintain B. hermsii and B. turicatae differ, human infections usually occur in rustic cabins (B. hermsii) and caves (B. turicatae) inhabited by ticks and their terrestrial vertebrate hosts (1). Recently, Gill et al. (4) provided evidence that the argasid bat tick, Carios kelleyi, feeds upon humans. Subsequently, Loftis et al. (5) used PCR analysis and DNA sequencing to detect in C. kelleyi an unidentifi ed Borrelia species that was closely related to B. turicatae and B. parkeri.

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The morphology of the gas bladder and associated structures in sea catfishes (Siluriformes: Ariidae) is studied. The most simple gas bladder, exclusive to Galeichthys Valenciennes, is apple-shaped with weakly developed internal trabeculae, has smooth walls externally and a short Mullerian window associated with a broad, short Mullerian ramus that is firmly attached to Baudelot`s ligament and supracleithrum. Most genera of Ariidae have a cordiform bladder with well-developed trabeculae, smooth walls externally, an elongate Mullerian window and an elongate Mullerian ramus with an acute tip that is free from the Baudelot`s ligament and supracleithrum. Sciades proops (Valenciennes) and S. parkeri (Traill) have a similar gas bladder but with a well-developed secondary chamber. Other genera of Ariidae also have a cordiform bladder with well-developed trabeculae and elongate Mullerian window, but with lateral diverticula present as shallow rounded bulges or blister-like swellings along the peripheral margins of the bladder. The degree of development of lateral diverticula varies among and within species, with Osteogeneiosus Bleeker having the most highly-developed diverticula. Bagre pinnimaculatus (Steindachner) and Bagre bagre (Linnaeus) have unusual depressed gas bladders with complex network of internal trabeculae. The implications of gas bladder morphology for the taxonomy and phylogenetic relationships of the family are discussed.

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The aim of the study was to evaluate rickettsial infection in ticks from wild birds of the Semidecidual and Atlantic Rainforest remnants of three municipalities of the State of Parana, southern Brazil. Overall, 53 larvae and nymphs collected from birds were checked for the presence of Rickettsia DNA by molecular tests. Five tick species were tested: Amblyomma aureolatum (Pallas), Amblyomma calcaratum Neumann, Amblyomma longirostre (Koch), Amblyomma ovale Koch, and Amblyomma parkeri Fonseca and Aragao. A. longirostre ticks were infected with the spotted fever group agents Rickettsia amblyommii strain AL (32.3% infection rate) and Rickettsia parkeri strain NOD (5.9% infection rate). A new rickettsial genotype was detected in the tick A. parkeri (50% infection rate), which had never been reported to be infected by rickettsiae. Through phylogenetic analysis, this new genotype, here designated as strain ApPR, grouped in a cluster composed by different strains of Rickettsia africae, Rickettsia sibirica, and R. parkeri. We consider strain ApPR to be a new genotype of R. parkeri. This study reports for the first time rickettsial infection in ticks from birds in southern Brazil. The role of migrating birds in the dispersal of these rickettsial strains should be considered in ecological studies of spotted fever group agents in Brazil.

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During November 2010, three ticks were collected from three dogs living in the rural area of Arica, northern Chile. Morphological analyses of the ticks in the laboratory revealed that they were most similar to Amblyomma maculatum Koch and Amblyomma triste Koch. However, because of unique metatarsal spurs, neither of the Chilean specimens could be assigned with certainty to A. maculatum or A. triste, based on external morphology. The mitochondrial 16S rRNA gene partial sequences obtained from two Chilean specimens were 99.5% identical to A. triste from Uruguay, and 99.0% identical to A. maculatum from the United States. Through phylogenetic analysis inferred from partial 16S rRNA sequences, the Chilean specimens were classified as A. triste. Molecular analyses also showed that one of the three Chilean ticks was infected by Candidatus 'Rickettsia andeanae'. These findings extend the geographical distribution of A. triste to Chile, where no tick-associated rickettsia had been reported previously.

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Engraved title vignette.

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Effective detection of population trend is crucial for managing threatened species. Little theory exists, however, to assist managers in choosing the most cost-effective monitoring techniques for diagnosing trend. We present a framework for determining the optimal monitoring strategy by simulating a manager collecting data on a declining species, the Chestnut-rumped Hylacola (Hylacola pyrrhopygia parkeri), to determine whether the species should be listed under the IUCN (World Conservation Union) Red List. We compared the efficiencies of two strategies for detecting trend, abundance, and presence-absence surveys, underfinancial constraints. One might expect the abundance surveys to be superior under all circumstances because more information is collected at each site. Nevertheless, the presence-absence data can be collected at more sites because the surveyor is not obliged to spend a fixed amount of time at each site. The optimal strategy for monitoring was very dependent on the budget available. Under some circumstances, presence-absence surveys outperformed abundance surveys for diagnosing the IUCN Red List categories cost-effectively. Abundance surveys were best if the species was expected to be recorded more than 16 times/year; otherwise, presence-absence surveys were best. The relationship between the strategies we investigated is likely to be relevant for many comparisons of presence-absence or abundance data. Managers of any cryptic or low-density species who hope to maximize their success of estimating trend should find an application for our results.