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1.
This article presents a summary of what has been achieved during the last 20 years within the project ‘The hawkweeds (Hieracium s.s.) of Sweden’ in general, and concerning Hieracium sect. Vulgata in particular, a review of our present understanding of the taxonomy and evolution of this group, as well as some new results and classifications that will be implemented in a forthcoming monographic treatment of the section in Swedish. A complete nomenclatural checklist (including synonyms and type material) of the 229 accepted species is included as an appendix and these species have been assigned to 23 informal species aggregates based on a multi‐variate analysis based on morphology and what is known about their ploidy level and molecular variation. Complete lists of the morphological characters considered important in the group as well as relevant literature are also included as appendices. Seven species are described as new to science or newly elevated to the rank of species: H. anderssonii T. Tyler, H. chroocentrum (Dahlst. ex Zahn) T. Tyler, H. cramiceps T. Tyler, H. hemimaculatum T. Tyler, H. maculato‐ornatum T. Tyler, H. ragnarii T. Tyler and H. vietulifolium (Johanss. & Sam.) T. Tyler.  相似文献   

2.
Among Swedish Hieracium sect. Oreadea (Fr.) Arv.‐Touv., more than 100 taxa have been recognized by various experts but, except for a regional monograph from 1894 there are no thorough published revisions of the group and many of the names have never been validly published. At the same time, some of the oldest names have been variously applied to morphologically clearly different species. In the present study, 5000 specimens in Swedish herbaria have been revised using both traditional and statistical morphometric methods and the complicated nomenclature has been disentangled. Twenty‐eight species are recognized and described with diagnostic keys and illustrations aiding identification and their known distributions are mapped. Six species are described as new to science (viz. H. marinum T. Tyler, H. eulasium Dahlst. ex T. Tyler, H. victoriae T. Tyler, H. falcifolium Johanss. ex T. Tyler, H. guldbergense Folin ex T. Tyler and H. hispidosum Dahlst. ex T. Tyler) and 3 additional names are raised to the specific rank (viz. H. gigantocybe (Dahlst.) T. Tyler, H. hilare (Dahlst. ex Omang) T. Tyler and H. tanyphyllum (Dahlst. ex Zahn) T. Tyler). Lectotypes are designated for 50 names based on material from Sweden, Norway or Finland and one name is neotypified. Except for a few infraspecific names for which all original material appears to be lost, all names based on material from Sweden are typified. However, it is concluded that albeit the number of taxa is relatively low, the species of H. sect. Oreadea are morphologically less distinct and clear‐cut than those of other widespread Scandinavian sections of the genus. Many of the characters that are most important in other sections of the genus are either invariable or unreliable in H. sect. Oreadea. Thus, the taxonomy has to rely on characters more subjected to environmentally‐induced modification. Furthermore, members of this section exhibit great morphological plasticity, possibly connected to their preference for exposed rocky habitats where the environmental conditions may be both severe and unpredictable.In addition, due to their ecological demands, they are confined to habitats that have always been both strongly fragmented and restricted in size giving rise to multiple small and locally adapted local populations. The section is here circumscribed in agreement with previous Scandinavian authors, i.e. including both the H. schmidtii‐group sometimes referred to H. sect. Stelligera and the H. norvegicum group approaching H. sect. Tridentata, but it is concluded that the section is relatively heterogeneous and that further studies aiming at the identification of more natural supraspecific taxa are much needed.  相似文献   

3.
Lectotypes are designated for 174 names of taxa described based on material from the Swedish province of Dalarna and accepted to belong to Hieracium sect. Hieracium , sect. Bifida and sect. Vulgata . The taxonomic and nomenclatural implications, i.e. taxonomic synonyms and infraspecific taxa not worthy of taxonomic recognition, of the lectotypifications are discussed. Three new combinations, H. mundulifolium (Johanss.) T. Tyler, H. oligasterum (Johanss. & Sam.) T. Tyler and H. transtrandense T. Tyler, are proposed to accommodate the infraspecific taxa H. gilvocaniceps Johanss. var. mundulifolium Johanss., H. expallidiforme (Dahlst. ex. Stenstr.) Dahlst. var. oligasterum Johanss. & Sam. and H. insuccatum Johanss. var. occidentale Johanss. & Sam. respectively, when treated at the rank of species.  相似文献   

4.
Pseudostellaria tianmushanensis G. H. Xia & G. Y. Li, collected from the Tianmu Mountains Nature Reserve in northwestern Zhejiang, China, is described and illustrated. This new species is similar to P. rupestris Pax., but differs by having a string of fusiform or ovoid‐globose tubers, leaves that are narrow elliptic‐lanceolate, glabrous, with cuneate base with scattered multi‐nodulate hairs, papillate margins and basipetalous variation in floral morphology. Moreover, the seed tubercle ornamentation also supports the recognition of the new species. A key to the species of Pseudostellaria in Zhejiang province is provided.  相似文献   

5.
Five new bryozoan species (Buffonellaria cornuta, Lagenipora chedopadiensis, Turbicellepora canui, T. naniberensis andT. rostrata) belonging to the family CelleporidaeHINCKS, 1884 are described and illustrated from the Tertiary sequences of western Kachchh, Gujarat, India. The zoaria of these species comprise about 17 percent of total cheilostome bryozoan colonies from Kachchh in the present collection, and those ofTurbicellepora rostrata n. sp. account for over 64 percent of the celleporid specimens. These records of celleporids enrich our knowledge of the fossil occurrence of this group during the Early Miocene in the Indo-Pacific province.  相似文献   

6.
Teucrium andrusi, described by Post from Mardin province, Turkey, was synonimized with T. paederotoides in the flora of Turkey. According to the records in the flora of Turkey T. paederotoides was a steno‐endemic species, only known from the type locality in Gaziantep and from Mardin province. Specimens of T. paederotoides s.l. were collected from both localities and a detailed comparison of the plants from Gaziantep with those from Mardin revealed that the two populations were sufficiently distinct from each other to be recognised as separate species. Thus, T. andrusi Post is reinstated from the synonymy with T. paederotoides. Teucrium andrusi is morphologically different from T. paederotoides s.s. in terms of its general indumentum, leaf margin, bract and calyx shape, corolla colour and nutlet macro–micromorphology. It can be anatomically distinguished from T. paederotoides s.s. by stoma type, stomatal distribution on the leaf surface, crystal content in the cells and cuticula thickness. Ecological data related with the accompanying species also support species status for T. andrusi. While the two taxa are very similar in pollen and nutlet morphology, trichome density on the nutlets are different.  相似文献   

7.
Collection of 1327 ticks sampled throughout Greece, Bulgaria, Romania and Croatia, from 211 tortoises belonging to three species, Testudo marginata Schoepff, T. graeca Linnaeus, and T. hermanni Gmelin, revealed the presence of four species of ixodid ticks, namely Hyalomma aegyptium (Linnaeus), Haemaphysalis sulcata Canestrini and Fanzago, H. inermis Birula and Rhipicephalus sanguineus (Latreille). Study confirmed the strong dominance of all life stages of H. aegyptium among ticks parasitizing west Palaearctic tortoises of genus Testudo Linnaeus. Furthermore, a considerable portion of ticks collected from tortoises in southwestern Bulgaria represent larvae and nymphs of H. sulcata. At the same area we collected as exception one larva and one nymph of H. inermis from a single specimen of T. hermanni. Our findings of four adults of R. sanguineus is the first record of this species from reptilian host. According to our results achieved on localities with syntopic occurrence of two tortoise species, T. marginata and T. graeca represent in the Balkans the principal hosts of H. aegyptium, whereas T. hermanni serves only as an alternative host in the areas close to range of either T. marginata or T. graeca.  相似文献   

8.
Tetrahymena mitochondrial cox1 barcodes and nuclear SSUrRNA sequences are particularly effective at distinguishing among its many cryptic species. In a project to learn more about Tetrahymena natural history, the majority of >1,000 Tetrahymena‐like fresh water isolates were assigned to established Tetrahymena species with the remaining assigned to 37 new species of Tetrahymena, nine new species of Dexiostoma and 12 new species of Glaucoma. Phylogenetically, all but three Tetrahymena species belong to the well‐established “australis” or “borealis” clades; the minority forms a divergent “paravorax” clade. Most Tetrahymena species are micronucleate, but others are exclusively amicronucleate. The self‐splicing intron of the LSUrRNA precursor is absent in Dexiostoma and Glaucoma and was likely acquired subsequent to the “australis/borealis” split; in some instances, its sequence is diagnostic of species. Tetrahymena americanis, T. elliotti, T. gruchyi n. sp., and T. borealis, together accounted for >50% of isolates, consistent with previous findings for established species. The biogeographic range of species found previously in Austria, China, and Pakistan was extended to the Nearctic; some species show evidence of population structure consistent with endemism. Most species were most frequently collected from ponds or lakes, while others, particularly Dexiostoma species, were collected most often from streams or rivers. The results suggest that perhaps hundreds of species remain to be discovered, particularly if collecting is global and includes hosts of parasitic forms.  相似文献   

9.
Species diagnosis is of the utmost importance to both pest management and plant quarantine services. Because of difficulties in the morphological diagnosis of spider mites, molecular techniques are of great value to rapidly and accurately diagnose closely related species. We examined four species of genus Tetranychus (the green and red forms of T. urticae, and T. kanzawai, T. phaselus and T. truncatus), which are found in Korea and are of significance to plant quarantine services. DNA samples isolated from a single egg, larva or adult weighed 64–188 ng. We designed species‐specific primers by performing sequence alignment for 107 sequences of the ribosomal internal transcribed spacer 2 (ITS2) region, which we obtained from GenBank, and sequences generated in this study. Specific nucleotides of each species were selected for designing primers specific for each species. Each species‐specific primer pair, when used to perform PCR analyses, detected only the species from which it originated. However, a T. urticae‐specific primer pair did not discriminate between the green and red forms of this species. These species‐specific primers can be applied in practice for the rapid and accurate diagnosis of spider mite species in plant quarantine and in agricultural fields.  相似文献   

10.
The diversity of hard tick fauna was studied in different forest communities in 48 localities of eastern Croatia using the dragging‐flagging method and by hand from ten different vertebrate hosts. A total of 2,225 specimens comprising seven species in three genera were identified. Ixodes ricinus, the most abundant species (72.8% of all collected specimens) was recorded in 44 localities, followed by Dermacentor reticulatus in 19 localities, while the other five species (D. marginatus, H. concinna, H. inermis, I. canisuga, and I. hexagonus) were recorded in fewer localities. The highest ratio (67% of collected ticks) was in the adult stage with the predominance of females. The numbers of collected females, males, and nymphs of I. ricinus and H. concinna differed significantly. Ten new tick‐host associations in Croatia were recorded. Fifty‐three animals were infested with one tick species. Single species infestation with I. ricinus was found in 45.8% of animals, followed by D. reticulatus with 25.4%, D. marginatus with 10.2%, H. inermis and I. hexagonus with 3.4%, and I. canisuga with 1.7%. Coinfestation with two species of ticks were recorded in six animals. Ixodes ricinus, H. inermis, and D. reticulatus showed bimodal seasonal activity; for other species unimodal activity patterns were recorded.  相似文献   

11.
Tuber indicum, an endemic truffle species in eastern Asian, is an edible mushroom that is both an important export and widely distributed across China. Many existing studies on truffles focus on analyzing their taxonomy, population genetics, volatile organic compounds and artificial cultivation of the truffles, while little information is available about their nutrient composition and pharmacological activity, especially the relationship between chemical composition in ascocarps and their geographic distributions. This study presents a comprehensive investigation of the chemical composition of T. indicum, including free sugars, fatty acids, organic acids, phenolic acids, flavonoids, and polysaccharides, and tracks the antioxidant activity of T. indicum ascocarps collected from five geographical regions of four provinces in P. R. China: Hebei, Tibet, Yunnan, and Liaoning province. Our results showed that T. indicum collected from Qujing, Yunnan province, possessed the highest amount of free sugars (23.67 mg/g dw), total flavonoids (2.31 mg/g dw), total phenolics (4.46 mg/g dw) and the highest DPPH and ABTS radical‐scavenging activities. The amount of water‐soluble polysaccharides was the highest (115.24 mg/g dw) in ascocarps from Tibet, the total organic acids was the highest (22.073 mg/g dw) in ascocarps from Gongshan, and polyunsaturated fatty acids were most abundant in those from Hebei province. This study reveals that the quantity of chemical compounds in T. indicum varies by geographical origin. Detecting differences in chemical composition may provide important data for understanding the relationship between environmental factors and truffle formation, as well as quality evaluation of the commercial species T. indicum throughout China.  相似文献   

12.
The volvocacean genus Pleodorina has been morphologically characterized as having small somatic cells in spheroidal colonies and anisogamous sexual reproduction with sperm packets. In this study we examined two new species that can be assigned to the genus Pleodorina based on morphology: P. starrii H. Nozaki et al. sp. nov. and P. thompsonii F. D. Ott et al. sp. nov. P. starrii was collected from Japan and had 32‐ or 64‐celled colonies with anterior somatic cells and spheroidal individual cellular sheaths that were weakly attached to each other within the colonial envelope. P. thompsonii from Texas (USA) exhibited four or 12 somatic cells in the anterior pole of 16‐ or 32‐celled colonies, respectively, and had a single large pyrenoid in the chloroplast of mature reproductive cells. The chloroplast multigene phylogeny placed P. starrii and P. indica (Iyenger) H. Nozaki in a clade that was robustly separated from the type species P. californica Shaw and P. japonica H. Nozaki. Pleodorina thompsonii was resolved as a basal branch within a large monophyletic group (Eudorina group) composed of Eudorina, Pleodorina and Volvox (excluding section Volvox). Thus, Pleodorina was found among three separate lineages within the Eudorina group in which Eudorina and Volvox were also resolved as nonmonophyletic. The DNA sequences from additional species/strains as well as recognition of morphological attributes that characterize the monophyletic groups within the Eudorina group are needed to construct a natural generic classification within these members of the Volvocaceae.  相似文献   

13.
It is difficult to differentiate similar trichodinids solely based on morphological examination, thus other identification methods, such as molecular identification, are necessary for identification. One mobilid ciliate named Trichodina pseudoheterodentata sp. n. was isolated from the gills of channel catfish, Ictalurus punctatus, in Chongqing, China. In the present study, its SSU rDNA was sequenced for the first time. Based on the results from both morphological identification and SSU rDNA sequencing, the new species was identified and compared with similar species. The morphological analysis revealed that T. pseudoheterodentata is a large Trichodina species (cell diameter 73.0–82.5 μm) and possesses robust denticles with broad blades and well‐developed blade connections. Characterization of its primary and secondary SSU rDNA structures indicated that T. pseudoheterodentata was distinctly different from congeneric species in H12, H15, E10_1, and V4 regions. Phylogenetic analysis revealed that the genetic distances among the new species and similar species reached interspecific levels, furthermore, the phylogenetic study also validated the identification of T. pseudoheterodentata and its placement in the genus Trichodina.  相似文献   

14.
Ticks may act as vectors for a number of infectious diseases including Crimean Congo Hemorrhagic Fever (CCHF). The causative agent is Crimean Congo Hemorrhagic Fever Virus (CCHFV), a member of Bunyaviridae, causing extensive ecchymosis, visceral bleeding and hepatic dysfunction with a high fatality rate in the affected individuals. CCHF was initially recognized in Turkey in 2002 and the current number of reported cases exceeds 4,400. This study was conducted to confirm the presence of tick species established as potential CCHFV vectors and investigate CCHFV activity in ticks at Ankara province, Turkey’s second most-densely populated province, where CCHF cases were demonstrated. A total of 1,196 adult ticks, collected from various animals and vegetation in 12 sites located in 5 counties of Ankara during April–July 2010 were identified to species level. Twenty-two tick pools from county K2 were also evaluated for the presence of CCHFV RNA via a one-step real-time RT-PCR assay and reactive results were further confirmed by an in house nested RT-PCR assay. Nine tick species were identified: Rhipicephalus bursa (44.9%), R. sanguineus (18.9%), R. turanicus (18.1%), Haemaphysalis parva (8.3%), Hyalomma marginatum marginatum (5.4%), H. aegyptium (1.4%), H. anatolicum excavatum (1.3%), Hae. punctata (0.3%) and Dermacentor marginatus (0.2%). A total of five tick pools (22.7%) were reactive in real-time and nested RT-PCR assays. The pools included R. bursa, H. m. marginatum and Hae. parva ticks, collected from mammal hosts from two villages in one county. This is the first documentation of CCHFV activity in ticks from Ankara province, which indicates requirement for detailed surveillance to predict high risk zones in the region.  相似文献   

15.
Trichogramma, polyphagous endoparasitoids of lepidopteran eggs, are used against a variety of crop pests throughout the world including those of sugar cane and corn in south‐eastern Asia. Their ability to be easily and economically reared on factitious hosts and their wide host range have contributed to their widespread use in pest control. The overall aim of this study was to select strains for eventual release in crop areas for control of lepidopteran borer pests of sugar cane and corn. To this end, we identified common Trichogramma species emerging from corn borer egg masses throughout south‐western Taiwan, compared their life‐history characteristics, assessed their thermal limits and identified the Wolbachia infection status of collected Trichogramma parasitoids. Trichogramma ostriniae was the most commonly collected species on corn, with occasional detection of T. chilonis and an unidentified species designated as T. sp. y. Although the sex ratio varied widely between sites, Wolbachia infection was detected only at a single site in one species (T. ostriniae). Wolbachia‐infected T. ostriniae were tolerant to high temperature stress. Trichogramma chilonis had lowest fecundity of the three species tested, and a Wolbachia‐infected T. ostriniae strain had lower fecundity than an uninfected strain. Given the limited availability of distribution and historical data for Trichogramma species in Taiwan, the current study provides a baseline for future work and also highlights the importance of accurately identifying species when establishing colonies of natural enemies for biocontrol.  相似文献   

16.
17.
The vine weevil Otiorhynchus sulcatus is a parthenogenetic reproducing species which forages for suitable host plants at night, but is found congregated in dark places during the day. Frass of this weevil species is suspected to contain attractive compounds that are host‐plant related. Using a still‐air olfactometer, we tested adult vine weevils at night for their behavioural response to odours from conspecifics, feeding on a mixture of spindle tree (Euonymus fortunei) and yew (Taxus baccata), and to a sexually reproducing related species (Otiorhynchus salicicola), feeding on a mixture of ivy (Hedera helix) and cherry laurel (Prunus laurocerasus). Their attraction to conspecifics and O. salicicola appeared to be related to frass production. Freshly collected frass from O. sulcatus and from O. salicicola males and females was attractive. Prunus laurocerasus and H. helix have not been observed to be hosts of the vine weevil in the field. However, our tests showed that the vine weevil was attracted to mechanically damaged leaves of both plant species, whereas undamaged leaves were not attractive. Only undamaged young unfolding leaves of H. helix were also attractive. The attraction to odours from mechanically damaged host and non‐host plants suggested the involvement of compounds that are commonly found in many plant species. The involvement of plant compounds and/or aggregation pheromones in attraction to frass of the vine weevil and frass of the related weevil species O. salicicola is discussed.  相似文献   

18.
Endogenous cytokinins, auxins, and abscisic acid (ABA) were identified and quantified in 11 red algae collected from the Brazilian coast. Field materials and two isolates cultured in the laboratory were extracted with various solvents and buffers containing a mixture of appropriate internal standards, purified by solid‐phase extraction followed by immunoaffinity chromatography, and analyzed by liquid chromatography–tandem mass spectrometry. Isoprenoid cytokinins (free and conjugated forms of isopentenyladenine [iP], cis‐zeatin [cZ], and trans‐zeatin [tZ]) were detected in all species with concentrations of cZ and iP forms being higher than tZ forms. Dihydrozeatin (DHZ) and its metabolites were only detected at very low levels in nine of the studied species. Aromatic cytokinins (6‐benzylaminopurine [BA], ortho‐ and meta‐topolin [oT and mT]) were not detected in any of the samples. The cytokinin profile of Chondracanthus teedei (Mert. ex Roth) Kütz. was distinct in comparison to other species with para‐topolin (pT) derivatives detected in low concentrations. The main auxins present in all species were free indole‐3‐acetic acid (IAA) and indole‐3‐acetamide (IAM). Indole‐3‐ethanol (IEt), indole‐3‐acetyl glutamic acid (IAGlu), and indole‐3‐acetyl leucine (IALeu) were detected in a few species at low concentrations. ABA was present in all species analyzed except for Hypnea nigrescens Grev. ex J. Agardh. No ABA conjugates were detected in any species. These results confirm that cytokinins, auxins, and ABA were common constituents in red seaweeds, with this being the first report of the occurrence of ABA in Rhodophyta. The complexity of the hormone profiles suggests that plant hormones play a role in regulating physiological processes in Rhodophyta.  相似文献   

19.
《Journal of morphology》2017,278(6):780-790
Tachyoryctes splendens (Northeast African mole‐rat) and Heliophobius emini (Emin's mole‐rat) are two African mole‐rats that represent separate allopatric rodent families namely Spalacidae and Bathyergidae respectively. While these species consume a similar diet of underground plant storage organs such as roots and tubers, T. splendens has been reported to additionally consume small amounts of aerial foliage. This study aims to provide detailed gross morphological and histological morphometric analyses of the gastrointestinal tract (GIT) of these two subterranean species. The formalin fixed gastrointestinal tracts of T. splendens (n = 9) and H. emini (n = 6) were photographed, weighed and measured. The length and basal surface areas were calculated for each anatomically distinct region. Representative histological samples were prepared and stained using Hematoxylin and Eosin. Microscopic luminal measurements were used to calculate a surface enlargement factor and the luminal surface area of each region. Tachyoryctes splendens had a large double chambered hemi‐glandular stomach with a macroscopically visible transition from keratinized stratified squamous epithelium to glandular epithelium. The cecum was large and the luminal surface revealed a single spiral fold. The ascending colon of T. splendens was arranged in a spiral, with two centripetal and two centrifugal windings. The descending colon was arranged in a single parallel loop, similar to H. emini . A narrow colonic groove was accompanied by V‐shaped folds on either side. Heliophobius emini had a simple glandular stomach, a large, haustrated cecum that displayed a cecal appendix and the descending colon was arranged in a single parallel loop. The internal aspect of the colon revealed a wide colonic groove extending from the ceco‐colic junction to distal colon. As both species originate from a similar geographical region and ingest very similar diets, it is likely that the differences in the GIT morphology are attributed to phylogeny as the species represent two different families of mole‐rats.  相似文献   

20.
In the laboratory, a dual culture primary screen using wheat straw agar (WSA) showed that 64 out of 152 selected fungi inhibited the in vitro growth of Pseudocercosporella herpotrichoides by 50% or more. An ‘asymmetric’ species of Penicillium isolated from wheat stubble was the most effective, inhibiting growth of the pathogen by 70%. The results were similar using both W‐type and R‐type isolates of P. herpotrichoides. Other fungi showing in vitro antagonism included: Trichoderma viride, T. koningii, T. harzianum, Chaetomium globosum, Acremonium persicum, Botryotrichum piluliferum, Sordaria alcina, Microdochium bolleyi, Rhizoctonia cerealis and Laetisaria arvalis.

In a glasshouse secondary screen, the 64 fungi showing antagonism in vitro were assessed further for their ability to reduce eyespot disease symptoms of wheat seedlings using a straw collar co‐inoculation technique. Of them, 13 fungi reduced disease symptoms significantly: a Chaetomium sp. from stubble, two Fusarium spp., a F. culmorum isolate T. viride, T. koningii, T. harzianum, B. piluliferum, M. bolleyi, L. arvalis, the ‘asymmetric’ Penicillium sp. and two unidentified fungi from stubble. A F. culmorum isolate was the most effective antagonist on average, giving disease reductions of 54 and 58% for the W‐type and R‐type of P. herpotrichoides respectively. M. bolleyi, T. harzianum and the F. culmorum isolate were the most effective antagonists of the W‐type, all three reducing disease by 54%. T. viride was most effective against the R‐type, reducing disease by 64%.  相似文献   


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