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1.

Background

Brucellosis is a chronic bacterial disease caused by members of the genus Brucella. Among the classical species stands Brucella neotomae, until now, a pathogen limited to wood rats. However, we have identified two brucellosis human cases caused by B. neotomae, demonstrating that this species has zoonotic potential.

Cases presentation

Within almost 4 years of each other, a 64-year-old Costa Rican white Hispanic man and a 51-year-old Costa Rican white Hispanic man required medical care at public hospitals of Costa Rica. Their hematological and biochemical parameters were within normal limits. No adenopathies or visceral abnormalities were found. Both patients showed intermittent fever, disorientation, and general malaise and a positive Rose Bengal test compatible with Brucella infection. Blood and cerebrospinal fluid cultures rendered Gram-negative coccobacilli identified by genomic analysis as B. neotomae. After antibiotic treatment, the patients recovered with normal mental activities.

Conclusions

This is the first report describing in detail the clinical disease caused by B. neotomae in two unrelated patients. In spite of previous claims, this bacterium keeps zoonotic potential. Proposals to generate vaccines by using B. neotomae as an immunogen must be reexamined and countries housing the natural reservoir must consider the zoonotic risk.
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New species of the weevil genus Sitona Germ. are described: Sitona transcaucasicus sp. n. from the highlands of the Republic of Nakhichevan (Azerbaijan), S. davidiani sp. n. from the highlands of Southern Daghestan (Russia), Republic of Nakhichevan, and Northeastern Turkey, and S. abchasicus sp. n. from subalpine and alpine belts of Abkhazia and southeasternmost Krasnodar Territory (Russia).  相似文献   

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The northern Neotropical region is characterized by a heterogeneous geological and climatic history. Recent studies have shown contrasting patterns regarding the role of geographic elements as barriers that could have determined phylogeographic structure in various species. Recently, the phylogeography and biogeography of Quercus species have been studied intensively, and the patterns observed so far suggest contrasting evolutionary histories for Neotropical species in comparison with their Holarctic relatives. The goal of this study was to describe the phylogeographic structure of two Neotropical oak species (Quercus insignis and Quercus sapotifolia) in the context of the geological and palaeoclimatic history of the northern Neotropics. Populations through the distribution range of both species were collected and characterized using nine chloroplast DNA microsatellite loci. Both oak species showed high levels of genetic diversity and strong phylogeographic structure. The distribution of genetic variation in Q. insignis suggested an influence of two major barriers, the Isthmus of Tehuantepec and the Nicaraguan Depression, while Q. sapotifolia exhibited a genetic structure defined by the heterogeneity of the Chortis highlands. The haplotype networks of both species indicated complex histories, suggesting that colonization from the Sierra Madre de Chiapas to central Mexico and from the north of the Nicaraguan Depression to the Costa Rican mountains may have occurred during different stages, and apparently more than one time. In conclusion, the phylogeographic structure of Neotropical oak species seems to be defined by a combination of geological and climatic events.  相似文献   

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The genus Otidea was recently monographed and studied phylogenetically, but knowledge of the diversity and distribution of Otidea species in China is fragmentary. In this study, collections from China were examined morphologically and included in phylogenetic analyses. Using LSU, TEF1-α, and RPB2 new species were placed within previously recognized clades in the genus. The results agree with both Genealogical Concordance Phylogenetic Species Recognition (GCPSR) and genetic divergence as previously reported. Three new species, Otidea hanseniae, Otidea korfii and Otidea purpureogrisea are recognized based on phylogenetic reconstruction using ITS, LSU, TEF1- α and RPB2. Comments on some incompletely known species are added. With the discovery of these three new species, the genus Otidea in China proves to be more diverse than previously recognized.  相似文献   

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Coccodiella is a genus of plant-parasitic species in the family Phyllachoraceae (Phyllachorales, Ascomycota), i.e., tropical tar spot fungi. Members of the genus Coccodiella are tropical in distribution and are host-specific, growing on plant species belonging to nine host plant families. Most of the known species occur on various genera and species of the Melastomataceae in tropical America. In this study, we describe the new species C. calatheae from Panama, growing on Calathea crotalifera (Marantaceae). We obtained ITS, nrLSU, and nrSSU sequence data from this new species and from other freshly collected specimens of five species of Coccodiella on members of Melastomataceae from Ecuador and Panama. Phylogenetic analyses allowed us to confirm the placement of Coccodiella within Phyllachoraceae, as well as the monophyly of the genus. The phylogeny of representative species within the family Phyllachoraceae, including Coccodiella spp., graminicolous species of Phyllachora and taxa with erumpent to superficial stroma from several host families, suggests that the genus Phyllachora might be polyphyletic. Furthermore, tar spot fungi with superficial or erumpent perithecia seem to be restricted to the family Phyllachoraceae, independently of the host plant. We also discuss the biodiversity and host-plant patterns of species of Coccodiella worldwide.  相似文献   

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Three Asian leaf beetles of the genus Chrysochus were investigated as potential biological control agents of Vincetoxicum rossicum and V. nigrum, invasive weeds in northeastern North America. Chrysochus chinensis and Ch. globicollis were collected from a field host in a different genus and subtribe. Preliminary no-choice laboratory tests with Ch. goniostoma showed that its physiological host range is too broad. Based on these data, we are not considering these three species as potential biological control agents of invasive Vincetoxicum species.  相似文献   

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A new species of mermithid nematode, Hexamermis popilliae n. sp. (Nematoda: Mermithidae) is described from the Japanese beetle Popillia japonica Newman in Italy, an area of new introduction for this invasive pest. The combination of the following characters separates H. popilliae from other members of the genus Hexamermis Steiner, 1924: adult head obtuse; amphidial pouches slightly posterior to lateral head papillae in female but adjacent to lateral head papillae in males; amphidial openings large, well developed; amphidial pouches elliptical in females and oblong in males; cuticular vulvar cone well developed, vulvar lips greatly reduced or lacking, vagina curved at tip where meeting uteri, without reverse bend (not S-shaped), spicules slightly curved, with a slight bend in the basal portion, approximately equal to body width at cloaca. This is the first record of a species of Hexamermis parasitizing the Japanese beetle Popillia japonica. The only previous mention of mermithid nematodes from P. japonica was an undescribed species of Psammomermis in North America. Hexamermis popilliae will be evaluated as a potential biological control agent in an integrated control program of the Japanese beetle in Italy.  相似文献   

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The genus Potos (Procyonidae) is currently recognized as a monotypic genus comprising the single species Potos flavus, the kinkajou. Kinkajous are widely distributed throughout forested habitats of tropical Central and South America, extending from eastern Brazil across central Bolivia, eastern Peru, northern Ecuador, Guianas, Suriname, Venezuela, Colombia, and then through Central America and into western Mexico. The taxonomic history of the species is complex, with seven or eight subspecies historically recognized to acknowledge the phenotypic variation among populations. In this study, the systematics and the evolutionary history of Potos flavus were investigated based on the mitochondrial gene cytochrome b, including specimens from a large range of localities, covering most of the distribution of the species, from central Middle America (Costa Rica and Panama) through South America (Ecuador, Peru, Bolivia, Brazil, Guyana, and French Guiana). Analyses of 30 Potos flavus sequences showed 27 haplotypes that were grouped in five main clades in all phylogenetic analyses. These clades suggested a high geographic structure with specimens from (1) Costa Rica, (2) Guianas and North Brazil, (3) North Peru, (4) Ecuador and Panama, (5a) interfluves Branco-Negro rivers in the Brazilian Amazon, (5b) Eastern Atlantic Forest, (5c) Amazonian lowlands east Negro river including Bolivia, Peru, and West Brazil. Each of these clades differs from 4.5 % to 9.3 % in their genetic distance estimates, which suggests that the specific status of some of these lineages should be reconsidered. Divergence dating and biogeographic analysis suggested that crown Potos diversified in the Miocene-Pliocene in South America, and geographic barriers, such as savannas and rivers, may have played a significant role in the kinkajou diversification.  相似文献   

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A number of fish groups, such as Gobiidae, are highly diversified and taxonomically complex. Extensive efforts are necessary to elucidate their cryptic diversity, since questions often arise about the phylogenetic aspects of new species. Clarifications about the diversity and phylogeny of the Bathygobius species from the southwestern Atlantic are particularly needed. Evidence has been accumulating on the Brazilian coast regarding the possible presence of new species while doubts remain about the taxonomic status of others. The taxonomic identification of some species of Bathygobius has been problematic, given their generally conservative external morphology, and several species are recognized as cryptic. This situation hinders understanding the real diversity in this taxon. Taken together, genetic, cytogenetic and morphometric analyses have been effective in identifying new species of this genus. Here we describe the karyotypic features and morphological patterns of three Western South Atlantic species of Bathygobius. Furthermore, its cytochrome c oxidase I (COI) gene sequences were compared with those of species from Central America, North America and the Caribbean. The broad analyses performed demonstrated an unsuspected diversity, leading to the identification of an un-described new species (Bathygobius sp.2) and the geographic redefinition of another, Bathygobius sp.1, undoubtedly a branch of B. geminatus, hitherto inaccurately identified as B. mystacium on the coast of Brazil.  相似文献   

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Based on light and scanning electron microscopical studies, two new gonad-infecting species of Philometra Costa, 1845, P. draco n. sp. and P. radiata n. sp. (Nematoda: Philometridae), are described from the marine perciform fishes Trachinus draco (Linnaeus) and T. radiatus (Linnaeus) (both Trachinidae), respectively, in the Gulf of Hammamet, off the northeastern coast of Tunisia. Philometra draco n. sp. and P. radiata n. sp. can be separated from other gonad-infecting species of this genus by the structures associated to the gubernaculum (e.g. dorsal protuberance, smooth field separating the dorsolateral longitudinal parts), as well as by the length of the body, spicules and gubernaculum. Philometra radiata n. sp. can be distinguished from P. draco n. sp. in having the dorsal side of the gubernaculum distal end provided with a median longitudinal smooth field demarcated by two dorsolateral lamellate parts. These two new species are the first philometrid species described from fishes of the family Trachinidae.  相似文献   

12.
The enigmatic species Ustilago tillandsiae is the only known smut fungus associated with Bromeliaceae. Its generic position is evaluated by morphological, physiological, and molecular phylogenetic analyses using large subunit rDNA sequences. Phylogenetic analyses resolved U. tillandsiae as a member of the Ustilaginales in a sister relationship to the lineage containing Tranzscheliella species. However, U. tillandsiae differs from Tranzscheliella species by the development of sori in flowers, a different structure of sori and a different type of spore ornamentation. Consequently, a new genus Pattersoniomyces is described to accommodate U. tillandsiae. The new combination Pattersoniomyces tillandsiae is substantiated. In the sexual stage (teleomorph), this species infects bromeliads: Tillandsia flabellata, Tillandsia leiboldiana, and Tillandsia sp. in Central America between southern Mexico and Costa Rica. The yeast stage (anamorph) of P. tillandsiae was found associated with the phylloplane of Canistrum improcerum and in water tanks (phytotelmata) of Vriesea minarum, two bromeliads occurring in northeast and southeast Brazil, respectively. The link between the teleomorph and anamorphic strains is supported by identical sequences of the D1/D2 domains of the large subunit rDNA. Pattersoniomyces represents the tenth endemic smut genus to the Americas, but the only one that occurs in both North and South America, being a truly neotropical genus. The host plant families of Ustilaginales are extended to the Bromeliaceae. As far as we know, Pattersoniomyces represents the single event of a host jump from Cyperaceae or Poaceae to Bromeliaceae, apparently without further species radiation on multiple bromeliad species and genera growing in South America.  相似文献   

13.
During investigation of the mycobiota in the Sea of Okhotsk, three new Penicillium species were isolated from subaqueous soils collected in the Sakhalin Gulf and in the northeastern part of the Sakhalin shelf, near the Piltun Bay. According to Raper and Thom’s classification, the newly described species P. piltunense, P. ochotense, and P. attenuatum belong to subsection Divaricata. Two analyses were performed to reveal the phylogenetic relationships of the putative new species with other Penicillium species. Phylogenetically, the new species are related to the members of the P. canescens group and share some morphological and physiological features with them. However, they differ in having a larger colony diameter that makes them similar to P. atrovenetum, P. coralligerum, and P. antarcticum. A detailed analysis based on ITS, combined β-tubulin and calmodulin datasets, and morphological features revealed that the new species formed a distinct group inside the P. atrovenetum subclade. Moreover, P. attenuatum differs from the other two species macro- and micromorphologically and may represent a distinct phylogenetic lineage.  相似文献   

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Fauchea guiryi Selivanova sp. n. (Rhodymeniales, Faucheaceae) from the Commander Islands (Russian Pacific coast) is described and illustrated. The new species is compared with closely related taxa of the family Faucheaceae and the genus Fauchea, among them those from the Pacific coast of North America.  相似文献   

18.
Two new species of the family Derbidae are described. Anticedusa gen. n. (tribe Cedusini) includes the recent A. loisae sp. n. (type species) from Costa Rica and A. dominicana sp. n. from the Miocene Dominican amber. Cedochrusa gen. n. (type species Cedusa quixoa Kramer from Panama) of the tribe Cedochreini also contains a new species, Cedochrusa luculenta sp. n. from Costa Rica. A new subtribe Eocenchreina subtrib. n. comprising genera Eocenchrea Muir, Melusa Em., and Anticedusa gen. n. is erected for Cedusini with the achilid venation of the clavus.  相似文献   

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