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1.
White blister rust is one of the most common diseases in Brassicaceae. Recently, molecular approaches revealed that apart from Albugo candida, several other more specialized species of the genus are causing this disease on Brassicaceae and the diversity of this group still remains largely unexplored. All newly described species have so far been sampled only from a limited geographic range, except for Albugo species which followed their invasive host from Europe to other continents. In this study we show that a previously unknown species of Albugo is causing white blister rust disease on two species of Strigosella. This species can be distinguished from other species of the genus Albugo both by its phylogenetic position and its unique oospore ornamentation that might be an adaptation to the harsh environment of the host plants. As a consequence, Albugo arenosa is described and illustrated as a new species, so far known from Strigosella africana in Iran and Spain, and Strigosella brevipes in Iran. Apart from Albugo candida and Albugo lepidii, this is the third hitherto known species of Albugo s. str. with a confirmed native distribution range of several thousand kilometres.  相似文献   

2.
Passively dispersing aquatic invertebrates such as Ostracoda in restricted aquatic habitats such as bromeliads remain an intriguing observation considering the highly specialised dispersal vectors needed for efficient colonisation. Here we describe a new species of Elpidium, Elpidium merendonense sp. n., collected from bromeliads in the cloud forest from Cusuco National Park, Honduras. Elpidium merendonense sp. n. is a small to medium-sized species that can be easily distinguished from its congeners by its unique outgrowth at the posterior end of the left valve, visible especially in females. The species was common all through the park occurring at a wide range of altitudes and in different species of bromeliads. This finding is the first freshwater ostracod species described from Honduras and is in agreement with the prediction that the genus Elpidium contains a large number of species with small geographic distributions. We update the list of described species of Elpidium and present a key to species.  相似文献   

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Populations of Trichuris spp. isolated from six species of sigmodontine rodents from Argentina were analyzed based on morphological characteristics and ITS2 (rDNA) region sequences. Molecular data provided an opportunity to discuss the phylogenetic relationships among the Trichuris spp. from Noth and South America (mainly from Argentina). Trichuris specimens were identified morphologically as Trichuris pardinasi, T. navonae, Trichuris sp. and Trichuris new species, described in this paper. Sequences analyzed by Maximum Parsimony, Maximum Likelihood and Bayesian inference methods showed four main clades corresponding with the four different species regardless of geographical origin and host species. These four species from sigmodontine rodents clustered together and separated from Trichuris species isolated from murine and arvicoline rodents (outgroup). Different genetic lineages observed among Trichuris species from sigmodontine rodents which supported the proposal of a new species. Moreover, host distribution showed correspondence with the different tribes within the subfamily Sigmodontinae.  相似文献   

5.
Four new species of ascomycetes, Ascotaiwania pennisetarum sp. nov., Diaporthe appendiculata sp. now., Diaporthe minutis sp. nov., and Oxydothis miscanthiecola sp. nov., are described from senescent culms of grasses in Hong Kong. Ascotaiwania pennisetarum is distinctive from other species in the genus as ascospores are narrower. Diaporthe minutis differs from the most similar Diaporthe species in having ascospores with bipolar mucilaginous pads, while Diaporthe appendiculata differs from other species in having ascospores with both a mucilaginous pad and appendages at both ends. Oxydothis miscanthicola differs from other species in the genus in having long fusiform ascospores, which taper to rounded apices or otherwise differ in shape and size. These new species are compared with existing species and illustrated with interference light micrographs. The Diaporthe species known to posses mucilaginous ascospore appendages are listed.  相似文献   

6.
One previously named and two new species of the tineid genus Erechthias Meyrick are described and illustrated from the small, remote, mid-Atlantic Ascension Island. With these additions the Lepidoptera fauna of Ascension now totals 38 known species. Little is known regarding the biology of the two new species of Erechthias, and none of the species has been reared from larvae from Ascension. Erechthias minuscula (Walsingham) is a widespread, largely pantropical species first described from the West Indies. Larvae of Erechthias minuscula are known to be scavengers on a wide variety of dead plant material. Erechthias ascensionae,new species, is one of two species of Erechthias now known to be endemic to the island. The other endemic species, Erechthias grayi, new species, is further remarkable in having wing reduction occurring in both sexes. It is one of the few species of Lepidoptera known where this extreme of brachyptery involving both sexes has evolved. The larvae of Erechthias grayi are believed to be lichenivorous, and larval cases suspected to represent this species are illustrated.  相似文献   

7.
Among the multiple factors involved in the decline of amphibians, competition with alien species remains understudied. In Western Europe, non-native marsh frogs (Pelophylax ridibundus and other sister species) have been widely imported for gastronomic purposes and have then often escaped from captivity. Apart from closely related species, the impact of the subsequent colonization of non-native species on native amphibians is still unknown. In this study, we analysed the response of a threatened species, the yellow-bellied toad (Bombina variegata), faced with the presence of alien frogs in mountain rivers in France. We studied the co-occurrence pattern of the native toad and the alien frog, while taking into account co-dependence of the detection rates in both species. We tested three main scenarios to explain a non-random pond occurrence for each species and to establish their respective habitat preferenda: (1) a pond-area-dependent scenario, predicting different responses from each species for a given pond size, (2) a fish-dependent scenario, predicting different responses from each species given the presence of fish in ponds, and (3) a floodplain-width-dependent scenario, predicting different responses from each species given the geomorphological characteristics of the floodplain. Taking into account site-specific covariates, we concluded that introduced frogs do not currently have an impact on the native population of the yellow-bellied toad.  相似文献   

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All sexually fertile strains in the Gibberella fujikuroi species complex are heterothallic, with individual mating types conferred by the broadly conserved ascomycete idiomorphs MAT-1 and MAT-2. We sequenced both alleles from all eight mating populations, developed a multiplex PCR technique to distinguish these idiomorphs, and tested it with representative strains from all eight biological species and 22 additional species or phylogenetic lineages from this species complex. In most cases, either an ~800-bp fragment from MAT-2 or an ~200-bp fragment from MAT-1 is amplified. The amplified fragments cosegregate with mating type, as defined by sexual cross-fertility, in a cross of Fusarium moniliforme (Fusarium verticillioides). Neither of the primer pairs amplify fragments from Fusarium species such as Fusarium graminearum, Fusarium pseudograminearum, and Fusarium culmorum, which have, or are expected to have, Gibberella sexual stages but are thought to be relatively distant from the species in the G. fujikuroi species complex. Our results suggest that MAT allele sequences are useful indicators of phylogenetic relatedness in these and other Fusarium species.  相似文献   

10.
Indoor fungi are a major cause of cosmetic and structural damage of buildings worldwide and prolonged exposure of these fungi poses a health risk. Aspergillus, Penicillium and Cladosporium species are the most predominant fungi in indoor environments. Cladosporium species predominate under ambient conditions. A total of 123 Cladosporium isolates originating from indoor air and indoor surfaces of archives, industrial factories, laboratories, and other buildings from four continents were identified by sequencing the internal transcribed spacer (ITS), and a part of the translation elongation factor 1α gene (TEF) and actin gene (ACT). Species from the Cladosporium sphaerospermum species complex were most predominant representing 44.7% of all isolates, while the Cladosporium cladosporioides and Cladosporium herbarum species complexes represented 33.3% and 22.0%, respectively. The contribution of the C. sphaerospermum species complex was 23.1% and 58.2% in the indoor air and isolates from indoor surfaces, respectively. Isolates from this species complex showed growth at lower water activity (≥ 0.82) when compared to species from the C. cladosporioides and C. herbarum species complexes (≥ 0.85). Together, these data indicate that xerotolerance provide the C. sphaerospermum species complex advantage in colonizing indoor surfaces. As a consequence, C. sphaerospermum are proposed to be the most predominant fungus at these locations under ambient conditions. Findings are discussed in relation to the specificity of allergy test, as the current species of Cladosporium used to develop these tests are not the predominant indoor species.  相似文献   

11.
The family Caloscyphaceae with a single genus, Caloscypha, has been considered to include a single species, C. fulgens. Study of an overlooked second species, Caloscypha incarnata from North Africa and Italy, using SSU, LSU rDNA, and morphology allows placement of this species in a new genus, Kallistoskypha, in the Caloscyphaceae. This fungus is found in association with Eucalyptus species. The species was recently redescribed from Spain under the name Marcelleina parvispora. Caloscypha fulgens, the type species of the genus Caloscypha, shows sequence variation from across its range.  相似文献   

12.
《Mycoscience》2014,55(6):456-461
Two new species, Melanoleuca leucopoda and M. porphyropoda, are described based on collections made from Shenyang City, Liaoning Province, China. Melanoleuca leucopoda is mainly characterized by its whitish stipe with fibrils and oblong spores with elongated warts. Melanoleuca porphyropoda differs from all other Melanoleuca species in lacking cystidia and in having decurrent gills and a purplish stipe. The sequences of internal transcribed spacer regions (ITS1-5.8S-ITS2) of Melanoleuca species were analyzed and the results indicated that two new species clustered into two clades and differed from the other species of the genus. The combination of morphological and molecular data confirmed that the two fungi are new species. The morphological similarity of the new species to other species of Melanoleuca and the systematic position of the two species based on molecular data are also discussed.  相似文献   

13.
Four assemblages of fossil organic-walled microphytoplankton from the Upper Callovian (Lamberti Zone), three from England and one from Scotland, are described. They comprise at least 50 species of dinoflagellate cysts, 18 species of acritarchs and 2 species of tasmanitids. After a review of the «Xanthidium pilosum problem, a revised diagnosis is proposed for Sentusidinium pilosum (Ehrenberg) and three new species, Sentusidinium creberbarbatum, S. sparsibarbatum and S. erythrocomum are proposed. The new family name Scriniodiniaceae is substituted for the now invalid family name Endoscriniaceae. The new genus Escharisphaeridia is proposed to contain two existing species, E. pococki (Sarjeant) and E. dictydia (Sarjeant). The present content of the genus Compositosphaeridium is examined; the new combination C. polonicum (Górka) is proposed and a new species, C. bulgaricum, is erected. One further new species of dinoflagellate cyst, Prolixosphaeridium anasillum, is proposed. The new term «peniplate is proposed for paraplates whose boundaries are penitabular in situation.One new species of acritarch, Solisphaeridium?rhachos, is described and the new combination Polygonium aster (Sarjeant) is proposed. Evidence for reworking of some of the species of Micrhystridium present in the Hackness Rock assemblage is noted, though it is considered that the majority of species in that assemblage are indigenous. It is considered that all four assemblages are derived from a single phytoplankton province, the differences between them resulting from environmental factors such as water depth or distance from a shoreline.  相似文献   

14.
A new species, Mortierella sugadairana, is described for a fungus forming homothallic zygospores with a club-shaped macrosuspensor and a microsuspensor originating from the macrosuspensor. The species was isolated from cool regions in Japan and morphologically and phylogenetically close to a heterothallic species M. parvispora, which is the first species reported as a heterothallic species in the genus. Mycelial growth of the species was limited at 30 °C, whereas two isolates of M. parvispora can grow. This may indicate that the species and M. parvispora adapted to different climates from a common ancestor involving differentiation of the manner of reproduction.  相似文献   

15.
Stylet ultrastructure of five Xiphinema, four Longidorus, and three Californidorus species was compared by scanning electron microscopy. Morphological differences were seen in the odontophores and odontostyle bases between the genera and some of the species. All Xiphinema studied had well-developed odontophore flanges; the Longidorus species lacked flanges, except for weakly developed ones in L. diadecturus; and none of the Californidorus had flanges. Three sinuses were present in the odontophores of all species. The sinuses varied in length depending upon species. In Xiphinema and Californidorus the odontostyle bases had distinct overlapping collars, but in Longidorus the collars were absent except for L. diadecturus. The odontostyle-odontophore junction from a lateral view appeared as a slanted transverse line in all the species, but in a dorsal view of Xiphinema and Californidorus it was V-shaped. Dorsal longitudinal seams of the odontostyle and odontophore were observed in all the species. The dorsally located odontostyle aperture was ca. 1 μm from the anterior end in all species, except in one Longidorus sp. it was ca. 4 μm from the end.  相似文献   

16.
A survey was performed to investigate the infection status of fishborne trematode (FBT) metacercariae in freshwater fish from Guangxi Zhuang Autonomous Region, China. A total of 307 freshwater fish of 31 species were collected from 5 administrative regions of Guangxi Zhuang Autonomous Region. They were examined by artificial digestion method from July 2003 to August 2004. No metacercariae were detected in fish from Fusui-xian. In fish from Mashan-xian and a market in Nanning, 3 species of metacercariae, Haplorchis taichui, Haplorchis pumilio, and Centrocestus formosanus, were mainly detected. Metacercariae (8 in number) of Clonorchis sinensis were found in 1 Chanodichthys dabryi purchased from a market in Nanning. In fish from Yangshuo, Metagonimus yokogawai metacercariae were detected from all 18 fish species examined. Total 13 C. sinensis metacercariae were found in 3 out of 10 Hemibarbus maculatus from Yangshuo. All 7 Zacco platypus from Yangshuo were infected with 8-112 Echinochasmus perfoliatus metacercariae. In fish from Binyang-xian, H. pumilo metacercariae were mainly detected in all 5 fish species examined, and only 1 metacercaria of C. sinensis was found in a Hemiculter leucisculus. From the above results, it was confirmed that some species of freshwater fish play a role of second intermediate hosts for FBT in Guangxi Zhuang Autonomous Region, China. In particular, 4 species of intestinal flukes, M. yokogawai, H. taichui, H. pumilio, and C. formosanus, were prevalent in fish hosts, whereas C. sinensis metacercariae were detected only in 3 fish species.  相似文献   

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18.
In this paper, the very first checklist of the freshwater leeches of Maloe More Strait, a special part of Lake Baikal, is presented. It includes 14 free-living and parasitic species, of which four species belong to endemic Baikal genera – two species from Baicalobdella and one species each from Baicaloclepsis and Codonobdella. The checklist highlights six potentially new morphological species recorded for the first time in the area. The exact systematic position is stated for all leech species. Each species from the list is provided with information on taxonomic synonymy, data on its geographic distribution, and ecological characteristics. New species records are additionally provided with brief morphological characteristics and photos of their external morphology.  相似文献   

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20.
The digestive systems of 86 canefield rats from Ingham, Queensland were examined for parasites. One species of cestode and seven species of nematode were found, all but one being new host records. The helminth community was characterised in terms of core, secondary and satellite species. No core species were identified, but Nippostrongylus typicus and Odilia emanuelae were identified as secondary species. All other species were identified as satellite species. The strongyloid nematode Ancistronema coronatum n. g., n. sp. is described. Ancistronema differs from other genera in the Chabertiidae in having a short buccal capsule and in the number and shape of the elements of the internal and external leaf crowns. This is the first record of a strongyle from Australian rodents. It is postulated that it came into Australia with ancestral Rattus sp. hosts which colonised Australia from Indonesia less than a million years ago.  相似文献   

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