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1.
The sorediate, saxicolous members of the Lecanora subfusca group, which include L. campestris ssp. dolomitica, L. caesiosora, L. pannonica , and L. umbrosa , although frequently misnamed, can be distinguished morphologically and chemically. Lecanora caesiosora is most variable, with a southerly form having a dark grey, thick thallus, and a more northerly, often shade-loving, morphotype having a very pale, thin thallus. The species are described, and a diagnostic key is presented including some confusable species. Lecanora pannonica and L. neglecta are neotypified.  相似文献   

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Chrysocapsopsis rupicola gen. et sp. nov. (Chrysophyceae) is described. It differs from Chrysocapsa and the closely related genera Chrysocapselia and Tetrachrysis by possessing both epiphytic and planktonic forms within the same life-history. Reproduction is by budding which produces short irregular branches within a gelatinous mass. Four or more aplanospores are produced from each mother cell; no motile cells were observed.  相似文献   

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Lecanora sabinae sp. nov. from the Canary Islands (El Hierro and La Gomera) is characterized chiefly by its greenish thallus with abundant pruinose apothecia ranging in colour from light yellow to almost black. It contains usnic acid, zeorin, and an unknown chemical product SAB-1, is by preference lignicolous and lives in association with the conifer Juniperus phoenicea.  相似文献   

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The diversity and phylogenetic position of photobionts in the widespread saxicolous, crustose lichen-forming ascomycete Lecanora rupicola s.l. is presented. The algal partners of this lichen species complex belong to diverse and unrelated lineages in the genus Trebouxia . Specimens were sampled from different habitats and geographical origins. Either whole thallus DNA extractions or minute fragments of the algal layer of the lichen thallus were subjected to polymerase chain reaction, using primers that specifically amplify internal transcribed spacer rDNA of the photobionts. No correlations between different chemical races of L. rupicola with particular lineages of Trebouxia spp. were found. Irrespective of the different algal partners, all lichen thalli abundantly developed ascomata. L. rupicola apparently maintains full fecundity with a low degree of selectivity for photobionts, which promotes the occurrence of this lichen-forming species in ample ecological situations.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 283–293.  相似文献   

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With 1,400 described species, Megaselia is one of the most species-rich genera in the animal kingdom, and at the same time one of the least studied. An important obstacle to taxonomic progress is the lack of knowledge concerning the phylogenetic structure within the genus. Classification of Megaselia at the level of subgenus is incomplete although Schmitz addressed several groups of species in a series of monographs published from 1956 to 1981. Another problem is the lack of molecular phylogenetic analyses to support morphology-based conclusions. As a contribution towards addressing these problems, we here circumscribe a previously unrecognized monophyletic lineage of Megaselia consisting of species similar to Megaselia lucifrons. We base this taxonomic decision on morphological study of an extensive phorid material from Sweden, complemented by molecular analyses of select exemplars using two markers (COI and 28S). We name the clade the lucifrons species group, and show that it contains three distinct species. Our results also demonstrate that Megaselia subnitida Lundbeck, 1920, previously treated as a synonym of Megaselia lucifrons Schmitz, 1918, is a separate species, and we remove it from synonymy. The third species in the group was previously unknown; we describe it here as Megaselia albalucifrons sp. n.  相似文献   

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Tropical evergreen forests of Indian subcontinent, especially of the Western Ghats, are known hot spots of amphibian diversity, where many new anuran species await to be identified. Here we describe from the Sharavathi River basin of central Western Ghats a new shrub-frog taxon related to the anuran family Rhacophoridae. The new frog possesses the characteristic features of rhacophorids (dilated digit tips with differentiated pads circumscribed by a complete groove, intercalary cartilages on digits, T-shaped terminal phalanges and granular belly, the adaptive characters for arboreal life forms), but also a suite of unique features that distinguish it from all known congeners in the region. Morphogenetic analysis based on morphological characteristics and diversity in the mitochondrial 12S and 16S rRNA genes revealed it to be a new Philautus species that we named Philautus neelanethrus sp. nov. The phylogenetic analysis suggests the new frog to represent a relatively early Philautus species lineage recorded from the region. The distribution pattern of the species suggests its importance as a bioindicator of habitat health. In general, this relatively widespread species was found distributed only in non-overlapping small stretches, which indirectly indicates the fragmentation of the evergreen to moist deciduous forests that characterize the Western Ghats. Thus the discovery of the new rhacophorid species described here not only further reinforces the significance of the Western Ghats as a major hotspot of amphibian biodiversity, but also brings into focus the deterioration of forest habitats in the region and the need for prioritization of their conservation.  相似文献   

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The bilbo element is a non-LTR retrotransposon isolated from Drosophila subobscura. We conducted a distribution survey by Southern blot for 52 species of the family Drosophilidae, mainly from the obscura and melanogaster groups. Most of the analyzed species bear sequences homologous to bilbo from D. subobscura. In the obscura group, species from the same species subgroup also share similar Southern blot patterns. To investigate the phylogenetic relationship among these elements, we analyzed eight copies of a short sequence of the element from several species of the obscura group. The obtained phylogram agrees with the phylogeny of the species, which suggests vertical transmission of the element.  相似文献   

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Variation at 12 pure-repeat dinucleotide microsatellites from Peromyscus maniculatus was analyzed for samples of all species in the P. maniculatus species group and P. leucopus. Except for one locus (Pml08) that amplified a product only for P. maniculatus, these microsatellites yielded reliable estimates of variation across these species; per-locus polymorphism and allele-size distribution were not significantly different among or between any of the species sampled from mainland populations. Significantly lower levels of variation and the distribution of alleles in the two populations of the insular-endemic P. sejugis were consistent with the expectation of substantial founder effect and suggest a lack of recent gene flow between these populations. Phenetic analyses of genetic distances based on shared allele frequencies uniformly produced well-supported trees that were entirely concordant with the a priori corroborated relationships within the P. maniculatus species group; this result was not obtained with analyses of a genetic distance computed from differences in allele sizes. The microsatellite data do not support the hypothesis that P. sejugis should be considered conspecific with P. maniculatus but yield a strongly supported sister-group association between P. sejugis and P. keeni.  相似文献   

13.
The phylogeny of the Lecanora varia group is inferred from ITS sequences using Bayesian and ML phylogenetic analysis methods. According to our data, usnic acid-containing, corticolous Lecanora species do not form a monophyletic group but occur in three major clades together with other groups of Lecanora and Protoparmeliopsis. The new combination Lecanora filamentosa (Stirt.) Elix & Palice is proposed. The new species Lecanora schizochromatica is described from northwestern North America. It produces atranorin as a major substance and is closely related to the morphologically and chemically similar L. filamentosa. The American Biatora pullula Tuck. is synonymised with Lecanora anopta Nyl., which is hereby reported for continental North America for the first time. The phylogenetic relationships between the major clades of Lecanora are still largely unresolved and require more intensive taxon and character sampling.  相似文献   

14.
The Anaxyrus boreas species group currently comprises four species in western North America including the broadly distributed A. boreas, and three localized species, Anaxyrus nelsoni, Anaxyrusexsul and Anaxyrus canorus. Phylogenetic analyses of the mtDNA 12S rDNA, cytochrome oxidase I, control region, and restriction sites data, identified three major haplotype clades. The Northwest clade (NW) includes both subspecies of A. boreas and divergent minor clades in the middle Rocky Mountains, coastal, and central regions of the west and Pacific Northwest. The Southwest (SW) clade includes A. exsul, A. nelsoni, and minor clades in southern California. Anaxyrus canorus, previously identified as paraphyletic, has populations in both the NW and SW major clades. The Eastern major clade (E) includes three divergent lineages from southern Utah, the southern Rocky Mountains, and north of the Great Basin at the border of Utah and Nevada. These results identify new genetic variation in the eastern portion of the toad's range and are consistent with previous regional studies from the west coast. Low levels of control region sequence divergence between major clades (2.2-4.7% uncorrected pair-wise distances) are consistent with Pleistocene divergence and suggest that the phylogeographic history of the group was heavily influenced by dynamic Pleistocene glacial and climatic changes, and especially pluvial changes, in western North America. Results reported here may impact conservation plans in that the current taxonomy does not reflect the diversity in the group.  相似文献   

15.
A Forsman 《Heredity》2015,115(4):276-284
Much research has been devoted to identify the conditions under which selection favours flexible individuals or genotypes that are able to modify their growth, development and behaviour in response to environmental cues, to unravel the mechanisms of plasticity and to explore its influence on patterns of diversity among individuals, populations and species. The consequences of developmental plasticity and phenotypic flexibility for the performance and ecological success of populations and species have attracted a comparatively limited but currently growing interest. Here, I re-emphasize that an increased understanding of the roles of plasticity in these contexts requires a ‘whole organism'' (rather than ‘single trait'') approach, taking into consideration that organisms are integrated complex phenotypes. I further argue that plasticity and genetic polymorphism should be analysed and discussed within a common framework. I summarize predictions from theory on how phenotypic variation stemming from developmental plasticity and phenotypic flexibility may affect different aspects of population-level performance. I argue that it is important to distinguish between effects associated with greater interindividual phenotypic variation resulting from plasticity, and effects mediated by variation among individuals in the capacity to express plasticity and flexibility as such. Finally, I claim that rigorous testing of predictions requires methods that allow for quantifying and comparing whole organism plasticity, as well as the ability to experimentally manipulate the level of and capacity for developmental plasticity and phenotypic flexibility independent of genetic variation.  相似文献   

16.
We describe a new genus of Mantophasmatodea, Viridiphasma gen. n. (Austrophasmatidae), represented by one new species, V. clanwilliamense sp. n. The new species differs from previously described species in features of the male and female postabdomen including the genitalia, in morphometrics and details of colouration. The new species occurs syntopically with another austrophasmatid, Karoophasma biedouwense Klass et al., 2003; this is the first well-documented case of sympatry of two mantophasmatodean species. We therefore survey the morphological differences between these two species, document the absence of any morphological evidence of hybridisation, and also report on differences in life history. While a previous molecular phylogeny using COI and 16S genes ambiguously placed V. clanwilliamense sp. n. near the base of Austrophasmatidae (but not as sister to all other Austrophasmatidae), morphological characters strongly support V. clanwilliamense sp. n. to be the sister taxon of a clade comprising all remaining Austrophasmatidae. This phylogenetic placement challenges the current hypothesis of a linear north-to-south diversification of Austrophasmatidae.  相似文献   

17.
系统发育分析结果表明,尽管Lanzia berggrenii能在寄主中形成基物子座,但与膜盘菌属的核心种关系较近,而与蜡盘菌科成员关系较远,应该归属于膜盘菌属。在广义的膜盘菌属的系统树中该种及在新西兰发现的4个新种构成一个单系群,分别命名为Hymenoscyphus haasticus,H. kiko,H.ohakune和H.waikaia。它们的共同特征:基物均为南青冈叶片,侧丝顶端分枝形成类似囊层被的结构,覆盖于子实层上部。Lanzia berggrenii var.metrosideri应为膜盘菌属中一个独立的种,即Hymenoscyphus metrosideri。  相似文献   

18.
Prototheca zopfii was isolated repeatedly from the nails of a patient. The patient had preexisting nail disease and colonization by the alga was opportunistic.  相似文献   

19.
Synopsis The coexistence of a fully developed falciform process and vitreal vessels, a hitherto unknown situation in teleostean intraocular vascularisation, has been noted in the loach Noemacheilus rupicola rupicola. Possible implications of this vascular development for the species have been highlighted.  相似文献   

20.
That closely related species often differ by chromosomal inversions was discovered by Sturtevant and Plunkett in 1926. Our knowledge of how these inversions originate is still very limited, although a prevailing view is that they are facilitated by ectopic recombination events between inverted repetitive sequences. The availability of genome sequences of related species now allows us to study in detail the mechanisms that generate interspecific inversions. We have analyzed the breakpoint regions of the 29 inversions that differentiate the chromosomes of Drosophila melanogaster and two closely related species, D. simulans and D. yakuba, and reconstructed the molecular events that underlie their origin. Experimental and computational analysis revealed that the breakpoint regions of 59% of the inversions (17/29) are associated with inverted duplications of genes or other nonrepetitive sequences. In only two cases do we find evidence for inverted repetitive sequences in inversion breakpoints. We propose that the presence of inverted duplications associated with inversion breakpoint regions is the result of staggered breaks, either isochromatid or chromatid, and that this, rather than ectopic exchange between inverted repetitive sequences, is the prevalent mechanism for the generation of inversions in the melanogaster species group. Outgroup analysis also revealed evidence for widespread breakpoint recycling. Lastly, we have found that expression domains in D. melanogaster may be disrupted in D. yakuba, bringing into question their potential adaptive significance.  相似文献   

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