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1.
Nuclear DNA content (2C) is used as a new criterion to investigate nearly all species of the genus Nerine Herb. The species have the same chromosome number (2n = 2x = 22), with the exception of three triploid plants found. The nuclear DNA content of the diploids, as measured by flow cytometry with propidium iodide, is demonstrated to range from 18.0–35.3 pg. This implies that the largest genome contains roughly 2 × 1010 more base pairs than the smallest. The species, arranged according to increasing genome size, fell apart in three groups if growth cycle and leaf width were also considered. A narrow-leafed, evergreen group with a DNA content between 18.0 and 24.6 pg contains thirteen species, a broad-leaved winter growing group with four species has a DNA content from 25.3–26.2 pg and a broad-leafed summer growing group has a DNA content of 26.8–35.3 pg and contains six species. If the presence of filament appendages and hairiness of the pedicels were also considered, the thirteen evergreen species could be further divided into a group without filament appendages or hairy pedicels with a DNA content of 18.0–18.7 pg. A second group without filament appendages but with hairy pedicels had a DNA content of 19.7–22.3 pg. And a third group with both filament appendages and hairy pedicels had a DNA content of 22.0–24.6 pg. The exception is N. marincowitzii that, despite a low DNA content and narrow leaves is summer growing. The broad-leafed group is further characterised by the absence of filament appendages and the absence of strongly hairy pedicels. The exception here is N. pusilla that, despite a high DNA content, has narrow leaves and minutely hairy pedicels. Nuclear DNA content as measured by flow cytometry is shown to be relevant to throw new light on the relationships between Nerine species.  相似文献   

2.
Spiromastix saturnispora, isolated from a soil sample collected from central Java in Indonesia, is described and illustrated as a new species. The new species was compared with the type ofSpiromastix, S. warcupii, and is similar in having brownish ascomata with a peridium of a loose network of delicate hyphae, peridial appendages which are curved in the manner of a scimitar and never completely coiled, and the absence of an anamorph. The ascospores ofS. saturnispora are characterized as large oblate, 3.2–4.8 × 2.5–3µm, punctate, and with an equatorial rim, which serves to distinguish the species fromS. warcupii and other known species.  相似文献   

3.
The leg genes extradenticle, homothorax, dachshund, and Distal-less define three antagonistic developmental domains in the legs, but not in the antenna, of Drosophila. Here we report the expression patterns of these leg genes in the prosomal appendages of the spider Cupiennius salei. The prosoma of the spider bears six pairs of appendages: a pair of cheliceres, a pair of pedipalps, and four pairs of walking legs. Three types of appendages thus can be distinguished in the spider. We show here that in the pedipalp, the leg-like second prosomal appendage, the patterns are very similar to those in the legs themselves, indicating the presence of three antagonistic developmental domains in both appendage types. In contrast, in the chelicera, the fang-like first prosomal appendage, the patterns are different and there is no evidence for antagonistic domains. Together with data from Drosophila this suggests that leg-shaped morphology of arthropod appendages requires an underlying set of antagonistic developmental domains, whereas other morphologies (e.g. antenna, chelicera) may result from the loss of such antagonistic domains.Edited by M. Akam  相似文献   

4.
A coelomycetous fungus occurring on culms of Pleioblastus sp. in Yakushima Island, southern Japan, is described and illustrated as a new species, Pseudolachnella yakushimensis. The species is characterized by cupulate, superficial black setose conidiomata, and cylindrical 3-septate conidia with two to five appendages at each end. Pseudolachnella yakushimensis is similar to P. indica and P. scolecospora by its 3-septate conidia, but is different from them by its smaller conidia with more than two appendages.  相似文献   

5.
Based on 18S, 5.8S, and 28S rDNA sequences, the phylogenetic position of Uncinula septata within the Erysiphales has been inferred. Although appendages of the ascomata are uncinula like, i.e., unbranched with curved-coiled apices, U. septata is situated at the very base of the large Erysiphales cluster, far away from the pseudoidium clade (Erysiphe emend., including Microsphaera and Uncinula). Morphologically, U. septata differs from the species of Erysiphe sect. Uncinula (Uncinula) in having terminal, pluriseptate ascoma appendages, curved ascospores, and the absense of an anamorph. This species is a basal, tree-inhabiting powdery mildew with some additional ancestral characteristics, viz., uncinula-like appendages and 8-spored asci. The new genus Parauncinula with U. septata as the type species is proposed. Uncinula curvispora (U. septata var. curvispora) is tentatively maintained as a separate species, which is also assigned to Parauncinula.  相似文献   

6.
蔡磊  BORAH Dipankar  刀志灵  温放 《广西植物》2020,40(10):1402-1408
通过查阅相关文献和标本,作者发现近期发表的苦苣苔科吊石苣苔属植物一新种——Lysionotus bijantiae D. Borah & A. Joe实为鉴定错误,应是汉克苣苔属的长圆叶汉克苣苔[Henckelia oblongifolia(Roxb.)D. J. Middleton & Mich. Möller] [原长圆叶唇柱苣苔Chirita oblongifolia(Roxb.)Sinclair]。Lysionotus bijantiae的模式标本采集于中国西藏东南部地区的喜马拉雅南坡,该地区苦苣苔植物多样性较为丰富。作者因其花具2枚发育雄蕊而将其归于吊石苣苔属,花萼分裂不达基部而与吊石苣苔属其他相关种类比较,而忽略了其种子先端不具附属物的特征。通过电镜扫描观察到,该种在墨脱境内居群以及其模式产地居群的种子均无附属物,从而证实了该种不是吊石苣苔属的物种,而是属于汉克苣苔属。因此,作者将Lysionotus bijantiae处理为Henckelia oblongifolia的新异名,同时提供了长圆叶汉克苣苔的彩色图片(含种子扫描图)、选定模式标本,并给出了吊石苣苔属和汉克苣苔属的区分方法和主要识别特征,不仅为这两个属的物种鉴定提供了参考,而且避免更多的物种分类混淆问题出现。  相似文献   

7.
TheSimaroubaceae generally have no true stipules. The stipule-like appendages of some genera proved to be pseudo- or metastipules (Weberling & Leenhouts 1965). There seem to be some exceptions, however: the generaCadellia (incl.Guilfoylia) andRecchia on the one hand, and theIrvingioideae on the other. As these taxa, with exception ofRecchia, have simple leaves, there are no indications that their stipule-like appendages might be pseudo- or metastipules. In regard to their position and ontogeny these appendages behave completely like true stipules. Assuming the view ofForman, one could conceive a morphological line from the long, broadly inserted axillary stipules of mostIrvingioideae to the small scaly triangular stipules ofIxonanthoideae. The similarities between the stipules ofIrvingioideae andErythroxylaceae (already emphasized byHallier and others), become even more evident when their ontogeny is investigated. TheIrvingioideae, therefore, might be regarded as a separate family (perhaps with some relation to theErythroxylaceae,Hallier) or as a subfamily ofIxonanthaceae (Forman).—In addition to data on stipules some results on the palynology and shoot anatomy of the generaCadellia (incl.Guilfoylia) andRecchia are reported. Their relationship with theSimaroubaceae also appears doubtful. If they are to be included, they represent a somewhat isolated group near the base of the family which otherwise has lost its stipules.
Herrn Univ.-Prof. Dr.Walter Leinfellner zum 70. Geburtstag gewidmet.  相似文献   

8.
Lasiobolidium gracile isolated from a soil sample collected from California, USA is described as a new species. This species is characterized by yellowish brown to reddish brown, nonostiolate ascomata with numerous, long straight appendages and a translucent peridium, subglobose to broadly clavate asci, hyaline to pale yellowish brown, ellipsoidal ascospores. It differs from the other species ofLasiobolidium in the straight and narrow appendages and the large ascospores. A key is presented separating the seven known species.  相似文献   

9.
Summary  The new species Cibirhiza spiculata Thulin & Goyder, from Acacia-Commiphora bushland on sand in the Somali National Regional State (Ogaden) of Ethiopia, is described and illustrated. Its conservation status has been assessed. A molecular phylogenetic analysis confirms its placement in the tribe Fockeeae and indicates a position of the new species as sister to C. albersiana. The almost obsolete anther appendages, the outer corona with spreading lobes, as well as the pollinia with apparently single pollen grains, also support its placement in Cibirhiza. However, C. spiculata differs markedly from both previously known species of this genus (C. dhofarensis in Oman and Yemen and C. albersiana in Tanzania and Zambia) by its narrowly linear, subsessile leaves and by the inner corona lobes that are curved inwards over the gynostegium and each ending in a spinulose head.  相似文献   

10.
Emericella appendiculata, a new species isolated from soil of the Pamire Plateau, is described and illustrated. It is characterized by grayish green non-ostiolate ascomata surrounded by a thick layer of hülle cells, membranaceous peridium, prototunicate asci, violet-brown, lenticular ascospores which are ornamented by two stellate equatorial crests, capitate convex surfaces, and long filiform appendages, and anAspergillus anamorph with biseriate conidiogenous cells.  相似文献   

11.
Moellerodiscus advenulus, a sclerotiniaceous fungus new to Japan, was collected and its ascospore morphology and cultural characteristics were studied. Ascospores possess previously unreported characters, such as gelatinous polar appendages and a sheath, and become brown and one-septate after discharge, prior to germination. The stromata produced in culture have a thin black rind typical ofLambertella. The taxonomic position ofM. advenulus is discussed, and a new combination,L. advenula, is proposed.  相似文献   

12.
The appendages of an insect are subdivided into distinct segments or podomeres. Many genes responsible for the regionalization of the growing limb into subdomains have been isolated from Drosophila. So far, only one gene is known in the leg that is solely required for specifying the distal-most pattern element—the pretarsal claw. In Drosophila, the gene aristaless is expressed in the centre of the antennal and leg imaginal disc that represents the most distal position of appendages, and in a proximal region. When Drosophila aristaless function is impaired, antennae and legs develop without their distal-most structures—the arista and the claw. We describe here the analysis of aristaless in the beetle Tribolium—an insect that shows a different, more ancestral mode of appendage formation than Drosophila. In Tribolium, appendages grow out continuously during embryogenesis, and no imaginal discs are formed. Tribolium aristaless (Tc-al) expression starts midway during appendage elongation, and is seen in a distal and a proximal position of head and trunk appendages. At the end of embryogenesis, Tc-al is seen in four expression domains in the leg, in the dorsal epidermis, and ventrally in every segment in lateral groups of cells, presumably the histoblasts. Like in the Drosophila adult, Tc-al is required in the larva for the formation of the most distal structures of the leg and the antenna as revealed by RNAi experiments. We conclude that aristaless is evolutionarily robust, meaning that it has retained its expressional and functional characteristics, although a heterochronic change of the process of appendage elongation took place towards the evolution of the highly derived diptera.Edited by D. Tautz  相似文献   

13.
Emericella qinqixianii, a new species isolated from desert soil from Sanchakou, Aksu, Qiemo, Yuli, Yutian, and the Taklimakan desert 100 km inland from Minfeng, Xinjiang Province, China, is described and illustrated. It is characterized by grayish yellow to olive brown, non-ostiolate ascomata surrounded by hyaline to pale yellowish brown hülle cells, membranaceous peridium, prototunicate asci, and violet-brown, lenticular ascospores with two equatorial crests, smooth convex surfaces, and long filiform appendages. It hasAspergillus anamorph with biseriate aspergilla.  相似文献   

14.
The tribal name Bocageeae Endlicher is reestablished and the tribe is circumscribed on the basis of solitary internodal ebracteate pedicels that are articulated at the base, and pollen shed in polyads of eight or more grains. Septate anther locules, large pollen size, and seed appendages are prevalent in the tribe. Intectate pollen with free-standing columellae, rare in Annonaceae, occurs not only in the genusTrigynaea but also in some species ofBocagea andHornschuchia. As defined here, the Bocageeae include seven neotropical genera:Cymbopetalum, Porcelia, Bocagea, Cardiopetalum, Froesiodendron, Hornschuchia, andTrigynaea. The latter five genera are revised and the treatments include ten new species:Cardiopetalum plicatum, Froesiodendron urceocalyx, Hornschuchia lianarum, H. santosii, H. leptandra, Trigynaea cinnamomea, T. lanceipetala, T. triplinervis, T. lagaropoda, andT. axilliflora, all from tropical South America. A new combination,Froesiodendron longicuspe, changes the rank of that taxon from subspecies to species.Cardiopetalum surinamense is removed fromFroesiodendron and reassigned toCardiopetalum on the basis of its connate petals, dehiscent monocarps, and seeds with bilobed arils. A cladogram provides an explicit hypothesis of intergeneric relationships in the tribe. The new combinationOnychopetalum periquino, based onTrigynaea periquino, is made.  相似文献   

15.
A new type of exterilium larvae referable to Leptobrotula (Ophidiiformes: Ophidiidae) is described on the basis of two specimens (20.7+mm and ca. 35.4mmSL) collected from the tropical Indo-Pacific. They are characterized, in particular, by several elongated anterior dorsal fin rays supported by the large dorsal pterygiophores and the exterilium gut bearing filamentous appendages along the ventral border. It is suggested from larval evidence that Leptobrotula forms a distinct lineage with Brotulotaenia and Lamprogrammus, which may be placed in an expanded Brotulonaeniinae.  相似文献   

16.
The nature and origin of the arthropod labrum is a matter much under dispute. We show here that in Tribolium castaneum (Herbst, 1797) the labrum develops from two individual primordia, termed labral buds. Expression of the genes decapentaplegic (dpp) and wingless (wg) in these buds is identical to the buds of the metameric appendages (e.g. thoracic legs), except that the patterns are reversed. We propose that this reversal is the result of the rotation of the labral buds through an angle of approximately 180°. We also for the first time study dpp and wg expression in the fully developed labrum of older embryonic stages. Here, gene expression patterns show that the labrum proper is formed by fusion of the labral buds along their dorsal sides, while their ventral sides are facing outward forming the lateral sides of the fused labrum. Furthermore, we show that there are very similar patterns in another arthropod species, the spider Cupiennius salei (Keyserling, 1877), although in this species the labrum develops as a single structure and not from two separate primordia. However, in C. salei the expression of engrailed is also reversed in addition to the reversal of dpp and wg expression: engrailed is expressed in the anterior half of the labrum, and not in the posterior half like in the remaining appendages. Our results suggest that the arthropod labrum is derived evolutionarily from paired limb-bud-like primordia by rotation and fusion, and that this process is recapitulated ontogenetically to a different extent in different arthropod species.  相似文献   

17.
Nannizziopsis mirabilis, isolated from a soil sample collected from New Jersey, USA, is described as a new species. The ascomata are white to pale yellow, with a peridium of a network of loosely interwoven hyphae and simple, more or less straight, clavate appendages. The ascospores are hyaline, globose to subglobose, and ornamented with spiral bands or sometimes polygonal pits. The associated anamorph is assignable to the form genusChrysosporium.  相似文献   

18.
华西南毛茛科六新种和二新变种   总被引:1,自引:0,他引:1  
王文采 《广西植物》2013,(5):579-587
该文描述了自华西南东部发现的毛茛科翠雀属2新种和1新变种、唐松草属1新种、银莲花属1新种和1新变种,以及毛茛属2新种。  相似文献   

19.
Yukari Mizuta 《Mycoscience》2006,47(6):380-384
Two new species and one new variety of Oudemansiella (Agaricales) from Japan are described and illustrated: (1) Oudemansiella latilamellata sp. nov. (subgenus Xerula, section Radicatae) has relatively broad lamellae and broadly ellipsoid spores with a subacute apex; (2) Oudemansiella rhodophylla sp. nov. (subgenus Xerula, section Radicatae), growing in deciduous forests of Fagus crenata, Quercus crispula, etc., is characteristic in having lamellae tinted reddish; and (3) Oudemansiella amygdaliformis var. bispora var. nov. (subgenus Xerula, section Albotomentosae) is distinguished from the type variety by having two-spored basidia and grows in evergreen oak forests (Castanopsis sieboldii, Quercus glauca, etc.) or bamboo groves.  相似文献   

20.
王文采 《广西植物》2016,36(Z1):76-84
该文描述了自华西南东部发现的毛茛科翠雀属2新种和1新变种、唐松草属1新种、银莲花属1新种和1新变种,以及毛茛属2新种。  相似文献   

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