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1.
Ying Tian  Guo-Dong Ren  Qiang Li 《ZooKeys》2014,(426):111-118
This paper deals with a species-group carniolica of the genus Nacerdes from China. This species-group has seven known species/subspecies in the world and two of them are known from China. Nacerdes (Xanthochroa) arcuata sp. n. is a new species belonging to carniolica group. The species were collected from Anhui (Eastern China, 30°02''17.37"N, 118°50''1.72"E). A key to the species of the species-group from China is given along with a distribution map.  相似文献   

2.
Sequence data from a broad geographical region and different habitats show that the Inocybe praetervisa clade is comprised of four closely related species. These species of section Marginatae are characterized by having nodulose spores and a stipe that is abundantly pruinose only in the upper half. Inocybe praetervisa occurs in Southern Europe in mountainous mixed coniferous forests, and is not confirmed from Northern Europe. Inocybe rivularis occurs in northern boreal forests up to the lower alpine zone, associated with Betula in moist habitats, and is not confirmed from Southern Europe. Inocybe taxocystis is confirmed as a later synonym of I. favrei. The species has a wide geographical distribution range in Europe, mainly restricted to the alpine zone and moist soils, associated with Salix herbacea. Inocybe arctica is here described as a new species. It occurs in the arctic and higher alpine zones, associated with Dryas octopetala, Salix polaris, S. reticulata and S. herbacea. All species except I. arctica are shown to have an intercontinental distribution range and are confirmed from North America. Sequence data suggest the occurrence of one additional species in the alpine zone of China. A key to the species in the I. praetervisa group is provided.  相似文献   

3.
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   

4.
A molecular analysis of eight described species of seed gall nematode, along with six undescribed isolates from different hosts, has revealed a strong association between nucleotide sequence polymorphism and host status. Each anguinid nematode associated with a unique host produced a unique PCR-RFLP pattern for the ITS1 region. Anguina species that had been synonymized in the past, Anguina agrostis, A. funesta, and A. wevelli (Afrina wevelli), were readily discriminated. Two undescribed species from northern New South Wales and southeastern South Australia, reported to be vectors of Rathyaibacter toxicus in the disease called ''''floodplain staggers,'''' were differentiated by a single restriction enzyme, and both could be separated easily from A. funesta, the vector of R. toxicus in annual ryegrass toxicity. Other species differentiated in this study include A. agropyronifloris, A. graminis, A. microlaenae, A. pacificae, and undescribed species from host species Dactylis glomerata, Agrostis avenacea, Polypogon monospeliensis, Stipa sp., Astrebla pectinata, and Holcus lanatus. Phylogenetic analysis of the ITS1 region suggests that considerable anguinid genetic diversification has accompanied specialization on different host species.  相似文献   

5.
Diacodexeidae are the first representatives of Artiodactyla in the fossil record. Their first occurrence is at the very base of the Ypresian (earliest Eocene, 56.0 Ma) with Diacodexis, a genus well diversified during the early Eocene in Europe, especially during the MP7–MP8 + 9 interval. However, most of European species are documented by scarce material, retrieved from single localities. In this work, we describe new Diacodexis material from ~MP7 and ~MP8 + 9 localities of Southern Europe, including material of D. antunesi from Silveirinha, considered as the most primitive European Diacodexis species, and material from three localities from Southern France (Fordones, Palette, and La Borie). The new material documents Diacodexis premolar morphology and deciduous dentition which bear potentially important phylogenetic information, as well as astragali, including a specimen from Silveirinha that constitutes the earliest occurrence of an astragalus of the genus Diacodexis in the European fossil record. Investigation of the enamel microstructure reveals that early European species had a simple enamel pattern with one-layered Schmelzmuster composed of ‘basic’ radial enamel only, instead of the two-layered Schmelzmuster (thin radial enamel + thick layer of Hunter-Schreger bands) observed on North American species and so far considered to represent the primitive condition within Artiodactyla. In accordance with previous studies, our observations highlight that Diacodexis gigasei from Belgium is morphologically closer to the North American species D. ilicis than to D. antunesi from Portugal. The latter species, together with D. aff. antunesi from Fordones, appears to be morphologically closer to the Asiatic taxa D. indicus and D. pakistanensis. Finally, we found numerous similarities between D. cf. gigasei from Palette and D. gigasei, a result that challenges the intra-European provincialism that characterizes the earliest Ypresian. Diacodexis gigasei could be one of the rare species shared by the northwestern and southwestern European bioprovinces.  相似文献   

6.
Natural hybridization frequently promotes gene introgression among closely related species in sympatric populations, producing complex patterns of morphological variation. Therefore, a detailed understanding of the dynamics of interspecific gene flow and its morphological patterns is of widespread interest. We tested if introgressive hybridization promotes an increase in transgressive characters in comparison with the parental species. A sunflower species complex occurring in Mexico formed by two native invasive species, Tithonia tubaeformis and Tithonia rotundifolia, was analyzed using 46 morphological characters (leaf, flower and fruit) in five hybrid zones (N = 150 individuals) and two pure sites for each parental species (N = 80 individuals). In general, T. tubaeformis differed significantly from T. rotundifolia in all the examined characters, except six foliar and one inflorescence character. Morphological characters support the hypothesis of hybridization in this complex, even though both species remain morphological distinct in mixed stands. Individual hybrids appear to be a mosaic of parent-like (24.8 % of traits), intermediate (26.1 %) and transgressive (37.8 %) phenotypes (the remaining 11.3 % of the traits did not differ significantly from both parental species). Our results suggest that individuals from the same parental species were more similar among themselves than to putative hybrids, indicating occasional hybridization with segregation in hybrid types or backcrossing to parents. Evidence indicates a unidirectional pattern of gene flow toward T. rotundifolia.  相似文献   

7.
Ossicaulis is a small genus in the family Lyophyllaceae. Two known species, O. lachnopus, and O. lignatilis, are distributed in north temperate regions. The third taxon, O. yunnanensis sp. nov., is described from the alpine belt of subtropics of southwestern China, and this genus is also reported for the first time from China. Morphologically, the new species is characterized by its whitish basidiomata and very small basidiospores. Molecular analyses from the nuclear rDNA internal transcribed spacer region (ITS) show that the subtropical alpine species is distinct from hitherto known Ossicaulis species and has a close relationship to O. lachnopus.  相似文献   

8.
Erysiphe gracilis is a powdery mildew species that occurs on evergreen oak species belonging to Quercus subgen. Cyclobalanopsis in East Asia (China and Japan). In a previous report, we found that E. gracilis var. gracilis is divided into four genotypes each of them forming a separate clade with strong bootstrap support. In this study, we further investigated genotype speciation in E. gracilis var. longissima occurring on Q. acuta and Q. sessilifolia, and found that this variety is also divided into two distinct genotypes. These results suggested that E. gracilis represents a species complex consisting of six different species. Based on detailed morphological examinations correlating with results of molecular sequence analyses, we propose to divide E. gracilis into six species, encompassing three new species (E. uncinuloides, E. pseudogracilis, and E. longiappendiculata), one new name (E. longifilamentosa), and two known species (E. gracilis s. str. and E. hiratae). A key to the species concerned is provided.  相似文献   

9.
10.
Low levels of genetic diversity in endemic species are generally attributable to the small size of their populations. This lack of genetic variability will, predictably, be more evident in those species that occur in only one or a very few localities with a total population consisting of a few dozen individuals, or sometimes fewer (i.e. ‘extremely narrow endemics’, ENEs). We used allozyme electrophoresis to survey the genetic variability of Coristospermum huteri, an endemic species from the island of Majorca (Balearic Islands, W. Mediterranean Basin) with a single natural population of about 100 individuals. As expected, allozyme variability was virtually nil for this species (P = 8.3 %, A = 1.08, H e = 0.022), which seems to be a general rule for ENEs (mean H e = 0.057). A founder effect associated with a dispersal event from the continent is probably behind the lack of genetic diversity in this highly threatened species. Preservation of the mountain summit where the plant is found (Puig Major) is essential for the survival of C. huteri, and would also guarantee the conservation of other ENEs and rare and threatened species.  相似文献   

11.
A new species of Eimeria Schneider, 1875 from rainbow skinks, Carlia ailanpalai Zug and Carlia eothen Zug is described from specimens collected in Papua New Guinea (PNG). Oöcysts of Eimeria zugi n. sp. from one of one (100%) C. eothen are ellipsoidal to cylindroidal, with a smooth, colourless, bi-layered wall, measure 25.1 × 15.5 μm and have a length/width ratio of 1.6. The micropyle and the oöcyst residuum are absent, but a polar granule is present. The sporocysts are ovoidal to ellipsoidal and 10.3 × 7.1 μm in size and do not contain Stieda, sub-Stieda or para-Stieda bodies; and the sporocyst residuum is composed of a compact mass of large globules. The sporozoites are elongate, 12.8 × 2.9 μm in size, and contain anterior and posterior refractile bodies with a nucleus between them. This is the ninth species of coccidium described from skinks from PNG, and the new species described herein is apparently endemic to the skink genus Carlia (Gray).  相似文献   

12.
Coral mechanisms of resilience and resistance to stressors such as increasing sea surface temperature and ocean acidification must first be understood in order to facilitate the survival of coral reefs as we know them. One such mechanism is production of the protective surface mucopolysaccharide layer (SML). In this study, we investigated changes in the thickness of the SML in response to increasing temperature and acidification for the three Caribbean scleractinian coral species of the genus Diploria, which have been shown to exhibit differential resilience to disease and bleaching. Among the three species, Diploria strigosa is known to have a higher susceptibility to disease, Diploria labyrinthiformis is known to bleach more quickly, and Diploria clivosa is relatively unstudied. When temperature was increased from 25 to 31 °C over a 1- or 6-week period, the overall thickness of the SML decreased from 33 to 55 % for all three species. Average SML thickness at 25 °C for all three species ranged from 106 to 156 μm, while average thickness at 31 °C ranged from 64 to 86 μm. SML thickness was significantly different among species at 25 °C, but not at 31 °C. D. labyrinthiformis demonstrated lower fragment mortality due to thermal stress when compared to the other Diploria species. Acidification from pH 8.2 to 7.7 over 5 weeks had no effect on SML thickness for any species. The observed decrease in SML thickness in response to increased temperature might be attributed to a decrease in the production of mucus or an increase in the viscosity of the SML. These findings may help to explain the increased prevalence of coral disease during the warmer months, since increased temperature compromises an important aspect of coral innate immunity, as well as differences in disease and bleaching susceptibilities between Diploria species.  相似文献   

13.
The phylogenetic position of the African and Malagasy species of Pimpinella is assessed using nrDNA ITS sequence data and a representative sampling of the genus, including 16 species from Africa and Madagascar and 26 species from Eurasia. The results of maximum parsimony and Bayesian analyses of these data show that the African and Malagasy species ally with their Eurasian counterparts in Pimpinelleae. The genus Pimpinella is rendered paraphyletic by the inclusion of African Cryptotaenia and the small African and Malagasy endemic genera Frommia and Phellolophium. Within a paraphyletic Pimpinella, three major clades are recovered, with the African species occupying two of these clades. The current sectional classification of the genus, based predominantly on fruit vestiture, is largely artificial. Chromosome base number, however, was found to be consistent with the groupings recovered in the molecular analyses. Those African and Malagasy Pimpinella species with a chromosome base number of x = 11 and largely glabrous petals and fruits, form the earliest diverging clade together with Frommia, which also has a base count of n = 11 and glabrous petals and fruits. The remaining African species ally with several Eurasian species of Pimpinella and share a chromosome base number of x = 9 and usually hairy petals and fruits.  相似文献   

14.
A novel methanol assimilating yeast species Komagataella kurtzmanii is described using the type strain VKPM Y-727 (=KBP Y-2878 = UCD-FST 76-20 = Starmer #75-208.2 = CBS 12817 = NRRL Y-63667) isolated by W.T. Starmer from a fir flux in the Catalina Mountains, Southern AZ, USA. The new species is registered in MycoBank under MB 803919. The species was differentiated by divergence in gene sequences for D1/D2 LSU rRNA, ITS1-5.8S-ITS2, RNA polymerase subunit I, translation elongation factor-1α and mitochondrial small subunit rRNA. K. kurtzmanii differs from its phenotypically similar sibling species Komagataella pastoris, Komagataella pseudopastoris, Komagataella phaffii, Komagataella populi and Komagataella ulmi by absence of growth at 35 °C and inability to assimilate trehalose.  相似文献   

15.
Ninety-five specimens of 14 freshwater fish species from small streams in the Kuala Terengganu district and the Lake Kenyir Reservoir, Malaysia, were surveyed for coccidian infections. Six fish species proved to be infected with apicomplexans belonging to the genus Goussia. In all of these fishes Goussia species were found in unsporulated and semisporulated stages. Oöcysts of four species inhabiting the intestinal epithelium became sporulated in tap-water within 24 hours. In two fish species sporulation failed and only unsporulated oöcysts were recorded in the intestine. Three of the intestinal species finishing sporulation proved to be new to science and were described as Goussia malayensis n. sp., G. bettae n. sp. and G. pogonognathi n. sp. from Apocheilus panchax, Betta splendens and Hemirhamphodon pogonognatus, respectively. The fourth species, found in Trichogaster pectoralis, was identified as G. trichogasteri Székely &; Molnár, 1992, a species known from aquarium-cultured T. trichopterus.  相似文献   

16.
Xylodon subflaviporus (Hymenochaetales, Basidiomycota) is described as a new species collected from tropical and subtropical regions of East Asia. This new species is characterized by resupinate basidiocarps, a poroid hymenophore, pseudodimitic hyphal system, nodose-septate hyphae, four types of cystidia (capitate, acicular to cylindrical, subulate to ventricose, and apically-encrusted), and thin-walled, colorless, smooth and ellipsoid basidiospores. Bayesian, Maximum Likelihood and Maximum Parsimony algorithms were used to construct phylogenies inferred from the internal transcribed spacer (ITS) region of rDNA. Morphological and molecular studies, along with intercompatibility tests, confirmed the independent status of this species. Also, based on morphological and molecular evidence, six new combinations of Xylodon are proposed to accommodate species originally classified under Hyphodontia s.l., i.e. X. bubalinus, X. chinensis, X. mollissimus, X. nongravis, X. reticulatus and X. subtropicus. A key to known species of Hyphodontia s.l. with poroid, irpicoid or raduloid hymenophores is provided for the convenience in identification.  相似文献   

17.
The Japanese golden chanterelle commonly identified as Cantharellus cibarius was sampled in a broad range of forest vegetation. A total of 90 fresh and 11 herbarium specimens were examined microscopically, subjected to sequencing analysis of their nuclear ribosomal RNA (rDNA) and tef-1 genes, and their characteristics were compared with those of European C. cibarius. Based on morphological and ecological characteristics, basidioma samples from Japan were divided into four species. While specimens of Cantharellus sp. 4 from Hokkaido Island were included in the European C. cibarius clade phylogenetically, the other three species formed three unique clades. Among these, Cantharellus anzutake sp. nov. is sister to the clade of C. cibarius and was widely sampled from the northern limit of Honshu Island to the southern limit of Kumejima Island in Ryukyu Islands. Although C. anzutake was morphologically similar to C. cibarius, the two species were phylogenetically distinct. Other morphologically similar but genetically distinct chanterelle species from India exhibited macroscopic and microscopic differences compared with C. anzutake.  相似文献   

18.
Analysis of the feeding habits and trophic interrelationships between nine important fish species including Ambassis interruptus, Liza vaigiensis, Escualosa thoracata, Leiognathus decorus, Stolephorus indicus, Gerres oyena, Arius sagor, Sillago sihama and Ambassis kopsii utilizing an impacted coastal habitat revealed that the diets of most species underwent marked changes with ontogeny. Most of them had moderate food intake with fullness value ranging from 2.50–4.88. Variations of diet breadth and vacuity index were observed between species and size. New settlers of most species fed mainly on microcrustaceans especially calanoid copepods, before shifting to other food items. A multivariate analysis demonstrated that diet composition of the nine fish species differed from each other. However, significant overlaps between some fish species, including A. kopsii with G. oyena, E. thoracata with L. decorus, A. sagor with S. sihama and G. oyena with L. decorus, were detected by a Morisita-Horn index. This indicates that food partitioning with a slight competition among species occurs in this heavily impacted ecosystem.  相似文献   

19.
Although apicomplexans are a widely recognized and important parasitic group, little is known about those associated with invertebrates, such as reef-building scleractinian corals. To resolve the potential impact of apicomplexans on coral health, it is first necessary to further describe this group of putative parasites and determine their prevalence among host species. Here, it was hypothesized that apicomplexan prevalence would vary seasonally, similar to what occurs in other marine apicomplexans as well as some coral symbionts. To test this, Caribbean scleractinian species Porites astreoides, Montastraea (=Orbicella) annularis, M. (=O.) faveolata, and Siderastrea siderea were sampled seasonally from two reefs each in the Florida Keys and the Bahamas for 9- and 5.5-year periods, respectively. Utilizing a PCR-based screening assay, apicomplexan DNA was detected from most Floridian (80.1 %: n = 555/693) and Bahamian (90.7 %: n = 311/343) coral tissue samples collected over these multi-year periods. Furthermore, apicomplexan DNA was detected from nearly all (98.7 %: n = 78/79) single polyps sampled at multiple locations within six M. faveolata colonies, indicating little to no intracolonial variation in the screening assay. Mixed-model logistic regression was utilized to determine the effects of season, host species, and reef on apicomplexan prevalence. The model identified a significant seasonal effect, with the highest apicomplexan prevalence occurring during fall. There also was a large effect of host species, with apicomplexan prevalence significantly lower among S. siderea colonies relative to the other species. While reef did not have a significant effect in the full model, there was a significant difference in apicomplexan prevalence between Floridian and Bahamian reefs for S. siderea, implying regional differences in this host species. Despite seasonal and species-specific differences in prevalence, apicomplexans are ubiquitous constituents of these particular scleractinian coral species from Florida and the Bahamas.  相似文献   

20.
Fish of the genus Selene, known as lookdowns or moonfish, are one of the most morphologically derived groups of the family Carangidae, whose phylogenetic relationships are still largely unknown. In this study, we discuss karyoevolutionary aspects of three representatives of this genus from the Western Atlantic: Selene brownii (2n = 48; FN = 48), Selene setapinnis (2n = 46; FN = 48), and Selene vomer (2n = 48; FN = 50). Their body patterns were also investigated and compared to one another and in relation to two other species of different genera. Two mechanisms of karyotypic evolution seem to have acted in the diversification of this genus, namely pericentric inversions and centric fusions. Mapping of rDNA sequences showed that chromosome pairs bearing 5S rDNA sites are similar, whereas those bearing 18 rDNA sites are morphologically distinct while apparently also exhibiting interspecies synteny. Although the nucleolar organizer-bearing chromosomes are extremely efficient cytotaxonomic markers among Selene species, others cytogenetic patterns of these species are relatively conserved. Hybridization with telomeric probes (TTAGGG)n did not exhibit interstitial telomeric sites (ITS), especially in S. setapinnis, where, along with a reduction in diploid number, a large metacentric pair derived from centric fusion is present. Data obtained by geometric morphometrics enable a clear morphological distinction among the three species, as well as in relation to two other species of the genus Caranx and Oligoplites. Data obtained suggest that morphologic evolution in Selene species was primarily dissociated from visible changes that occurred at the chromosomal level.  相似文献   

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