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The genus Cantharellus is known to have a global distribution and to form ectomycorrhizal associations with a diverse set of host plants. Here we describe Cantharellus pseudoformosus as a species new to science with a possible association with Cedrus deodara. ITS and LSU data demonstrated that the material from India is distinct from Cantharellus formosus and other closely related species.  相似文献   

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Marine catenulid platyhelminths of the genus Paracatenula lack mouth, pharynx and gut. They live in a symbiosis with intracellular bacteria which are restricted to the body region posterior to the brain. The symbiont-housing cells (bacteriocytes) collectively form the trophosome tissue, which functionally replaces the digestive tract. It constitutes the largest part of the body and is the most important synapomorphy of this group. While some other features of the Paracatenula anatomy have already been analyzed, an in-depth analysis of the trophosome region was missing. Here, we identify and characterize the composition of the trophosome and its surrounding tissue by analyzing series of ultra-thin cross-sections of the species Paracatenula cf. polyhymnia. For the first time, a protonephridium is detected in a Paracatenula species, but it is morphologically reduced and most likely not functional. Cells containing needle-like inclusions in the reference species Paracatenula polyhymnia Sterrer and Rieger, 1974 were thought to be sperm, and the inclusions interpreted as the sperm nucleus. Our analysis of similar cells and their inclusions by EDX and Raman microspectroscopy documents an inorganic spicule consisting of a unique magnesium–phosphate compound. Furthermore, we identify the neoblast stem cells located underneath the epidermis. Except for the modifications due to the symbiotic lifestyle and the enigmatic spicule cells, the organization of Paracatenula cf. polyhymnia conforms to that of the Catenulida in all studied aspects. Therefore, this species represents an excellent model system for further studies of host adaptation to an obligate symbiotic lifestyle.  相似文献   

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Survey of seven strains determined as Septonema ochraceum (Dothideomycetes, inc. sed.) isolated from pine litter or obtained from public collections revealed three new species, Fusicladium cordae, F. sicilianum (Venturiaceae), Cladophialophora matsushimae (Herpotrichiellaceae) and a cryptic species morphologically identical to Devriesia americana (Teratosphaeriaceae), but phylogenetically distinct. Morphological survey and phylogenetic analysis using nucleotide sequence data from the nuclear ribosomal subunit genes indicate a close relationship within three species colonising pine litter needles, F. cordae, F. pini and F. ramoconidii. F. sicilianum is most related to F. rhodense. C. matsushimae represents a species belonging to one of the lineages of the polyphyletic genus Cladophialophora. None of the strains observed can be classified morphologically as S. ochraceum, of which the type material does not exist.  相似文献   

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The architecture of the musculature of the eutardigrade species Milnesium tardigradum Doyère, 1840, Hypsibius sp. and Ramazzottius oberhaeuseri (Doyère in Ann Sci Nat Zool Sér 2(14):269–369, 1840) is investigated by phalloidin staining and confocal laser scanning microscopy. There are methodological problems in staining eutardigrades due to physiological alterations under stress (anhydrobiosis) and due to penetration problems of the cuticle. It is helpful to fix specimens in the state of asphyxy, where animals are stretched following an oxygen shortage in their environment. The musculatures of all three species correspond in their general architecture, but differ in detail, such as in the number of muscles. All muscles are isolated muscle strands. There are on each body side two dorsal and one ventral muscle strands, in addition to a system of dorsoventral, lateral and lateroventral muscles. Seven median ventral attachment points give rise to dorsoventral, ventrolateral and appendage muscles. The appendages receive several muscles originating dorsally and ventrally. The number of muscles and the arrangement differ in each appendage. The fourth appendage shows the greatest differences with a far smaller number of muscles compared to other species. The musculature shows comparably few strict segmental patterns, for example, the musculature of each appendage differs from the other ones. By comparison with literature data on the same species and data of Macrobiotus hufelandi it can be shown that eutardigrades have a roughly comparable muscular architecture, but that there are several differences in detail. Dedicated to Professor Westheide on the occasion of his 70th birthday.  相似文献   

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Columba livia is an important reservoir and carrier of Cryptococcus neoformans, Cryptococcus uniguttulatus, Cryptococcus laurentii and Cryptococcus albidus. Upper digestive tract of this species is also known as a habitat for Cryptococcus neoformans. Given the increasing clinical interest of this microorganism, 331 swabs from crop and 174 dropping samples from pigeon lofts in Grand Canary Island have been studied. The obtained results show an extensive presence samples 81 positive (24.47%) of Cryptococcus spp. in analysed crops: 32 (9.66%) for C. neoformans, 24 (7.2%) for C. uniguttulatus, 23 (6.9%) for C. albidus and 2 (0.6%) for C. laurentii. In the same way, Cryptococcus spp was also isolated in 82 (47.13%), dropping samples: C. neoformans in 59 (33.9%), C. uniguttulatus, in 9 (5.17%), C. laurentii in 8 (4.59%) and C. albidus in 6 (3.44%) of the investigated samples, respectively. The cryptococcosis produced by species of cryptococci other than C. neoformans has become more important during the last decade, supporting the study on the role of pigeon in the epidemiology of this disease.  相似文献   

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The presence of Ixodes neuquenensis (Ringuelet, Notas Mus la Plata 12:207–216, 1947) (Acari: Ixodidae) parasitizing populations of Dromiciops gliroides Thomas, 1894 (Microbiotheria: Microbiotheriidae) at Chiloé Island confirms that this tick species is established in Chile. No preference of the ticks for sex or age of the host was observed.  相似文献   

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Karyological preparations were made from the testisacs of three medicinal leech species Hirudo medicinalis Linnaeus, 1758, H. verbana Carena, 1820 and H. orientalis Utevsky & Trontelj, 2005 . The samples originated from different populations in Azerbaijan, Kazakhstan, Russian Federation, Ukraine and Uzbekistan. The chromosome numbers were determined both from mitotic and meiotic stages of spermatogenesis using the propionic haematoxylin staining technique. All three species were found to have different haploid chromosome numbers: H. medicinalis 14, H. verbana 13 and H. orientalis 12, thus corroborating the validity of these taxa. The chromosomes can be classified as meta-, submetacentric and acrocentric. The chromosome numbers obtained are similar to that of the related species Haemopis sanguisuga (Linnaeus, 1758), which has 13 pairs.  相似文献   

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In this study, the Phanerotomini of Turkey collected between July 1959 and July 2004, are listed. A total of thirteen Phanerotomini species were determined, and six of these are reported for the first time from Turkey. Phanerotoma (Bracotritoma) permixtellae Fischer, 1968 was reared from a new natural host Recurvaria pistaciicola (Danilevskii, 1955) (Lepidoptera: Gelechiidae). With this present study an illustrated identification key for the Phanerotomini of Turkey is given. The distribution of the Phanerotomini species is discussed according to the phytogeographical provinces of Turkey.  相似文献   

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Phengaris (=Maculinea) arion is an endangered social parasite of Myrmica ants, and for a very long time was considered as specific to Myrmica sabuleti. Previous studies carried out in Poland suggested some discrepancies within this assumption, and therefore a much more intensive survey was undertaken. The host ant use of P. arion was studied at five sites in different types of biotopes in Poland, i.e. xerothermal grasslands where Thymus pulegioides was used as a larval food plant by the butterfly, and more or less sandy biotopes with Thymus serpyllum. Altogether nine Myrmica species were recorded, and considerable variation in species composition and density of nests was recorded. At four localities M. sabuleti proved to be the most common ant. A total of 529 Myrmica nests were examined, and only 20 of them contained larvae and pupae of P. arion. Host ants belonged to five different species, i.e. M. sabuleti, Myrmica scabrinodis, Myrmica schencki, Myrmica lobicornis and Myrmica hellenica. Only at one site (NE Poland) was a significant heterogeneity in parasitation rates among Myrmica species detected. M. lobicornis was the most often infested ant there, which may suggest local specialisation of the butterfly. Overall low parasitism rates may explain the vulnerability of P. arion in Central Europe but further studies are also necessary.  相似文献   

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Following a re-examination of the material treated under Barleria brevispina (Fiori) Hedrén in the recent Flora of Somalia account of the Acanthaceae, it is concluded that two distinct species are involved and Barleria compacta Malombe & I. Darbysh. is described here from north-eastern Somalia. Its affinities and conservation status are discussed.  相似文献   

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Both Engaeus sericatus and Cherax destructor are omnivorous crayfishes consuming a variety of food items. Materials identified in the faeces of both E. sericatus and C. destructor consisted of mainly plant material with minor amounts of arthropod animals, algae and fungi. The morphology of the gastric mill of C. destructor suggests that it is mainly involved in crushing of food material while the gastric mill of E. sericatus appears to be better suited to cutting of food material. Given this, the gastric mill of E. sericatus may be better able to cut the cellulose and hemicellulose fibres associated with fibrous plant material. In contrast, the gastric mill of C. destructor appears to be more efficient in grinding soft materials such as animal protein and algae. Both species accumulated high amounts of lipids in their midgut glands (about 60% of the dry mass) which were dominated by triacylglycerols (81–82% of total lipids). The dominating fatty acids were 16:0, 16:1(n-7), 18:1(n-9), 18:2(n-6), and 18:3(n-3). The two latter fatty acids can only be synthesised by plants, and are thus indicative of the consumption of terrestrial plants by the crayfishes. The similarity analysis of the fatty acid patterns showed three distinct clusters of plants and each of the crayfish species. The complement of digestive enzymes, proteinases, total cellulase, endo-β-1,4-glucanase, β-glucosidase, laminarinase and xylanase within midgut gland suggests that both C. destructor and E. sericatus are capable of hydrolysing a variety of substrates associated with an omnivorous diet. Higher activities of total cellulase, endo-β-1,4-glucanase and β-glucosidase indicate that E. sericatus is better able to hydrolyse cellulose within plant material than C. destructor. In contrast to E. sericatus, higher total protease and N-acetyl-β-d-glucosaminidase activity in the midgut gland of C. destructor suggests that this species is better able to digest animal materials in the form of arthropods. Differences in total cellulase and gastric mill morphology suggest that E. sericatus is more efficient at digesting plant material than C. destructor. However, the contents of faecal pellets and the fatty acid compositions seem to indicate that both species opportunistically feed on the most abundant and easily accessible food items.  相似文献   

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Invasive species are often hypothesized to have superior performance traits. We compared stress tolerance (as change in biomass) of the invasive macroalgae Codium fragile ssp. tomentosoides and Gracilaria vermiculophylla to the native macroalgae Fucus vesiculosus, Agardhiella subulata, Hypnea musciformis and Ulva curvata in Hog Island Bay, a shallow lagoon in Virginia, USA. We hypothesized that the success of the two aliens is due to their high tolerances of turbidity, sedimentation, desiccation, grazing and nutrient enrichment. Like many lagoons, Hog Island Bay is characterized by extensive intertidal mudflats, high turbidity and sedimentation, and high densities of omnivorous mud snails. Nutrient enrichment may also become a problem as land use practices in adjacent watersheds change. Contrary to our hypothesis, C. fragile was less resistant to sedimentation, desiccation and grazing than other algae and had low growth at all light and nutrient levels. This suggests that any superior performance of this invasive species compared to native algae is probably limited to microhabitats where stress is minimal and where bivalve shells facilitate recruitment and long-term persistence. In contrast, G. vermiculophylla was resistant to desiccation, burial and grazing, and was not negatively influenced by either high or low light or nutrient levels. These traits reflect the current success of G. vermiculophylla in already invaded lagoons and estuaries, and indicates that it will likely continue its spread in European and North American turbid and tidal soft-sediment systems.  相似文献   

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The life cycle and developmental stages of Aylax hypecoi (Trotter, 1913, Hymenoptera: Cynipidae: Aylacini) were studied in detail. Aylax hypecoi is known to induce galls in fruits of two Hypecoum species — H. imberbe and H. geslini (Papaveraceae) and the larva develops in host plant fruits. The morphology and development of egg, larva and pupa were investigated, which has previously not been done. The shape and size of terminal-instar larvae and associated galls are sex-specific. Overwintering stage, adult emergence and flying periods, and egg productivity were studied also.  相似文献   

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To explore the possibility of an effectively long-term preservation of the germplasm of the HR lines of medicinal plant Astragalus membranaceus, Gentiana macrophylla Pall., and Eruca sativa Mill., both cold storage and cryopreservation approaches were attempted and compared. After 5-month cold storage on half strength Murashige and Skoog (1962) (1/2 MS) agar medium (AM), up to 82.9, 75.7, and 100% of the A. membranaceus, G. macrophylla and E. sativa hairy roots (HRs) recovered growth, respectively. The survival rates of A. membranaceus and G. macrophylla HRs significantly decreased, whereas that of E. sativa HR was unchanged with the addition of increased levels of exogenous abscisic acid (ABA) during cold storage. Using the encapsulation–vitrification (EV) method for cryopreservation, the G. macrophylla HRs died, whereas up to 6 and 73% of the A. membranaceus and E. sativa HRs survived, respectively. The HR lines evaluated with both methods showed no significant differences in morphology and growth rate compared with controls that were not subjected to preservation methods. These results suggest that cold storage is a more suitable alternative for the HR lines of the three studied plant species and that specificity of plant species have profound effects on the effectiveness of preservation.  相似文献   

17.
Capsicum chinense is a recalcitrant species for in vitro morphogenesis, and up to date there is no efficient system for genetic transformation and regeneration of this species via somatic embryogenesis. Here, we carried out an in vitro transformation of C. chinense via Agrobacterium tumefaciens co-cultivation with a system that expresses the heterologous gene WUSCHEL from Arabidopsis thaliana. WUSCHEL has been shown to promote the transition from vegetative to embryogenic state when overexpressed. We tested if the expression of WUSCHEL in C. chinense would promote an embryogenic response in this species. After 15 days of induction, the segments of transformed stems begun to form globular structures, suggesting that heterologus WUSCHEL was active and involved in the process of morphogenesis.  相似文献   

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Ferruh Aşçi 《Biologia》2009,64(6):1146-1149
In this study, the structural characteristics, unique features, various organ measurements of males and females of the water mite Atractides (Atractides) turcicus sp. n. from Turkey are described. In addition, the study compares their characteristics with related species.  相似文献   

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