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1.
Bupleurum shanianum X. G. Ma & X. J. He, previously recognized in China as B. gracillimum, is proposed here as a new species. This new species and B. gracillimum differ in many morphological characters (flowering stem position, bract size, number of flowers per umbellule) and have non‐overlapping distribution ranges. Bupleurum shanianum is most similar to B. yunnanense Franch., but the new species has shorter cauline leaves, and umbellules usually with 4 bracteoles and 3–6(–9) flowers. Bupleurum shanianum is known from eastern Himalayas to western Sichuan.  相似文献   

2.
The objective of this study was to develop single‐step PCR species‐specific primers that reliably discriminate four economically important Xiphinema species (X. brevicolle, X. elongatum, X. ifacolum and X. longicaudatum) and X. diffusum that is taxonomically very similar to X. brevicolle. Each species‐specific reverse primer was located in the ITS‐1 rDNA region and was used in combination with a universal forward primer located in the 18S rDNA gene. Primer reliability was confirmed by screening seven and 11 populations, respectively of X. diffusum and X. elongatum. Potential species‐specific primers were also identified for X. brevicolle, X. longicaudatum and X. ifacolum, however too few populations of these species were available to thoroughly assess their reliability. For all species‐specific primers, specificity was demonstrated by the absence of cross‐reactions with 14 non‐target Xiphinema species. Multiplex PCR was effective and reproducible for two (X. longicaudatum and X. ifacolum) or three (X. brevicolle, X. diffusum and X. elongatum) of the target nematode species, thus improving the applicability of the diagnostic primers.  相似文献   

3.
Salvia petrophila G. X. Hu, E. D. Liu & Yan Liu, a new species from the Chinese provinces of north Guangxi and south Guizhou, is described and illustrated. The new species is similar to S. miltiorrhiza, but can easily be distinguished by its shorter, unbranched stem, subsucculent simple leaf, longer pedicel and corolla tube, oblong‐entire middle lobe of lower corolla lip and larger oblate pollen. It is included in S. sect. Drymosphace on the basis of its falcate‐compressed upper corolla lip and connivent posterior connectives. Trichome and pollen micromorphology of the new species and similar species are described and compared. Additionally, assessment of the conservation status, current geographical distribution and notes on ecology of the new species are given.  相似文献   

4.
Carex dapanshanica X. F. Jin, Y. J. Zhao & Z. L. Chen, a new species of Cyperaceae from Mount Dapan, Zhejiang Province, eastern China is described and illustrated. The new species is morphologically similar to C. chungii C. P. Wang, but differs in having 2 or 3spikes, pistillate scales with brown margins and short‐awned at apex, and glabrous perigynia. Micromorphological photographs of the achenes of C. dapanshanica and C. chungii under SEM (scanning electron microscope) are provided as well.  相似文献   

5.
The taxonomic problem of cryptic species has long been recognized. Hemiboea subcapitata C. B. Clarke is a widespread and morphologically diverse species including two varieties, H. subcapitata var. subcapitata C. B. Clarke and H. subcapitata var. guangdongensis (Z. Y. Li) Z. Y. Li. However, genetic distance and molecular phylogenetic analyses based on nuclear ITS and four plastid DNA sequences (atpB‐rbcL, matK, rbcL, rpS16 intron) revealed that H. subcapitata var. guangdongensis is sister to H. subacaulis, and separated from H. subcapitata var. subcapitata, suggesting that it should be raised to the rank of an independent species as H. guangdongensis (Z. Y. Li) X. Q. Li & X. G. Xiang, comb. & stat. nov. Morphologically, the new species can be distinguished from H. subacaulis by its calyx 5‐sect from base, segments narrowly oblong‐lanceolate (versus calyx 5‐sect from base or 2‐lipped and adaxial lip 2‐lobed from below middle, segments ovate), peduncle glabrous (versus pubescent), and vermiform sclereids dispersed in leaf mesophyll (versus without sclereids).  相似文献   

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Didymodon mesopapillosus J. Kou, X.‐M. Shao & C. Feng is described and illustrated as a new species from Tibet, China. It is characterized mainly by its ovate to ovate‐lanceolate leaves appressed to weakly erect when dry, margins recurved from leaf base to apex, laminal cell superficial walls markedly thicker than the internal walls, laminal papillae present only on both sides of costa, short‐excurrent costa, undifferentiated basal cells and differentiated perichaetial leaves. This species is compared with similar species and its ecology is discussed.  相似文献   

8.
A new marine heterotrophic dinoflagellate species, Protoperidinium belizeanum sp. nov., from a coral reef‐mangrove pond was identified from scanning electron micrographs. Recognition of this new species was based on unique features of the thecal morphology, which included cell size and shape, presence of short and wide postcingular plates, sulcal architecture, antapical spines, and intricate thecal plate patterns of ridged hexagonal depressions. The thecal plate formula is as follows: Po, X, 4′, 3a, 7″, 4C (3+t), 6S, 5?, 2″″. Species association of P. be‐lizeanum sp. nov. within the genus Protoperidinium, its habitat, and associated dinoflagellates species are discussed.  相似文献   

9.
Oreocharis duyunensis Z.Y. Li, X.G. Xiang et Z.Y. Guo (Gesneriaceae), endemic to Guizhou, China, is described as a new species. The new species is easily distinguished from other Oreocharis species by having a white, stellate ring‐like disc. Morphologically, the species is similar to Oreocharis chienii (Chun) Mich. Möller & A. Weber but differs by its densely white pilose leaves, mixed brown‐pilose, pubescent and glandular‐pubescent peduncle and pedicle, white stellate ring‐like disc, and linear‐lanceolate capsule. Based on phylogenetic reconstruction and interspecific genetic distances of nuclear ITS and chloroplast trnL‐F regions, O. duyunensis is a new species with uncertain phylogenetic position.  相似文献   

10.
Two new species of Parnassia, Parnassia zhengyuana M.X. Ren & J. Zhang and P. simianshanensis M.X. Ren, J. Zhang & Z.Y. Liu, have been found in mountainous areas of Chongqing City, southwest China, and are described and illustrated here. Parnassia zhengyuana is found in a limestone cave near Mt Jinfo, Nanchuan District, Chongqing City. This tiny plant has special spoon‐shaped leaves and undivided staminodes with green apices. Parnassia simianshanensis was discovered in Mt Simian, Jiangjin County, Chongqing City. This species grows along streams on red sandstones, i.e. in Danxia landform. It can be easily identified by its unique rhombic leaves and the five‐ or four‐branched staminodes. The conservation status of P. zhengyuana and P. simianshanensis are assessed respectively as ‘Critically Endangered’ (CR) and ‘VU’ (Vulnerable) according to IUCN criteria. The roles of karst and Danxia landforms in the speciation process are discussed.  相似文献   

11.
A new genus of Pfiesteria‐like heterotrophic dinoflagellate, Luciella gen. nov., and two new species, Luciella masanensis sp. nov. and Luciella atlantis sp. nov., are described. These species commonly occur with other small (<20 μm) heterotrophic and mixotrophic dinoflagellates in estuaries from Florida to Maryland and the southern coast of Korea, suggesting a possible global distribution. An SEM analysis indicates that members of the genus Luciella have the enhanced Kofoidian plate formula of Po, cp, X, 4′, 2a, 6″, 6c, PC, 5+s, 5?, 0p, and 2″″. The two four‐sided anterior intercalary plates are diamond shaped. The genus Luciella differs from the other genera in the Pfiesteriaceae by a least one plate in the plate tabulation and in the configuration of the two anterior intercalary plates. An SSU rDNA phylogenetic analysis confirmed the genus as monophyletic and distinct from the other genera in the Pfiesteriaceae. The morphology of Luciella masanensis closely resembles Pfiesteria piscicida Steid. et J. M. Burkh. and other Pfiesteria‐like dinoflagellates in size and shape, making it easily misidentified using LM. Luciella atlantis, in contrast, has a more distinctive morphology. It can be distinguished from L. masanensis and other Pfiesteria‐like organisms by a larger cell size, a more conical‐shaped epitheca and hypotheca, larger rhombic‐shaped intercalary plates, and an asymmetrical hypotheca. The genus Luciella is assigned to the order Peridiniales and the family Pfiesteriaceae based on plate tabulation, plate pattern, general morphology, and phylogenetic analysis.  相似文献   

12.
Gutiérrez‐Gutiérrez, C., Palomares‐Rius, J.E., Cantalapiedra‐Navarrete, C., Landa, B.B., Esmenjaud, D. & Castillo, P. (2010). Molecular analysis and comparative morphology to resolve a complex of cryptic Xiphinema species. —Zoologica Scripta, 39, 483–498. During nematode surveys in cultivated and natural environments in southern Spain nine populations of parthenogenic Xiphinema species tentatively identified as Xiphinema cf. pyrenaicum and one population morphologically close to Xiphinema turcicum were detected. Surveys in southern France also identified one population resembling X. pyrenaicum. We developed a comparative study among these related Xiphinema species, including topotypes of two species of this group previously synonymized, viz. Xiphinema hispanum and Xiphinema sphaerocephalum, by considering morphological and morphometrical features together with molecular data from nuclear ribosomal RNA genes (D2‐D3 expansion segments of 28S, ITS1, and partial 18S). Morphological and morphometrical results identified eight of the Spanish populations as Xiphinema nuragicum (previously synonymized with X. pyrenaicum) whereas the ninth population was identified as Xiphinema adenohystherum (also synonymized with X. pyrenaicum). The species X. adenohystherum, X. nuragicum, X. pyrenaicum, and X. sphaerocephalum were shown to be morphologically almost indistinguishable but clearly separated by phylogenetic analyses, thus constituting a complex of cryptic species. Consequently, X. adenohystherum, X. nuragicum, and X. sphaerocephalum were re‐established as valid species. Similarly, X. hispanum (morphologically similar to X. aceri) was also shown as a valid species. Xiphinema turcicum, morphologically related to X. pyrenaicum complex by its rounded tail, uterus with a pseudo‐Z‐differentiation and small spines, was phylogenetically distant to these species based on D2‐D3 expansion segments of 28S and ITS1, which suggests a morphological convergence in their evolution.  相似文献   

13.
Impatiens pterocaulis S. X. Yu et L. R. Zhang, a new species of the Balsaminaceae from Yancha, Longlin, Guangxi Region, is described and illustrated. This species is similar to I. wilsonii in having nearly white flowers, 4 lateral sepals and a racememos inflorescence, but differs by having winged stems, very short‐spurred lower sepal, yellowish flowers and an acuminate dorsal petal apex. Pollen characters and leaf epidermal micro‐characters of these two species were studied, and the results support that the two species should be kept separate.  相似文献   

14.
Ilex sanqingshanensis, a new species of Aquifoliaceae from Jiangxi, China, is described and illustrated with morphological characteristics and ultrastructure of pollen grains. The new species is easily distinguished from the most similar species I. wugongshanensis C. J. Tseng ex S. K. Chen et Y. X. Feng by having smaller leaves that are elliptic, ovate or elliptic‐ovate, with shorter (0.5–1.0 vs 2–3 mm) teeth on the leaf margin, longer pedicels of staminate flowers (2.0–3.5 vs 1.5 mm), smaller pyrenes (3.5–4.0 × 2.0–2.5 vs 4.5–5.0 × 3.0 mm), and woody pyrenes (vs stony pyrenes).  相似文献   

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The taxonomy, host range and geographical distribution ofOligolecithus Vercammen-Grandjean, 1960, a genus of telorchiid digeneans fromXenopus spp. in Africa, is reviewed.O. jonkershoekensis Pritchard, 1964 is established as a junior synonym ofO. elianae Vercammen-Grandjean, 1960, andO. siluranae n. sp. is described fromX. tropicalis in Ghana. These two species are differentiated by variations in body length, testicular arrangement and ventral sucker width in proportion to body size.O. elianae occurs inX. laevis laevis from South Africa and Zimbabwe (new locality record),X. l. poweri from Zaire,X. l. victorianus from Zaire, Uganda and Rwanda (new locality record),X. l. bunyoniensis (new host record) from Uganda andX. l. sudanensis from Sudan (new host and locality record). It is also found inX. wittei from Uganda and Zaire andX. vestitus (new host record) from Uganda. The host ofO. siluranae belongs to a separate species group within the genusXenopus from the hosts ofO. elianae; this tropicalis group is phylogenetically isolated, but it also occurs in a different biotype, lowland tropical rain forest, ecologically distinct from the other known host species.  相似文献   

18.
Pfiesteria shumwayae Glasgow et Burkholder is assigned to a new genus Pseudopfiesteria gen. nov. Plate tabulation differences between Pfiesteria and Pseudopfiesteria gen. nov. as well as a maximum likelihood phylogenetic analysis based on rDNA sequence data warrant creation of this new genus. The Kofoidian thecal plate formula for the new genus is Po, cp, X, 4′, 1a, 6′′, 6c, PC, 5+s, 5′′′, 0p, 2′′′′. In addition to having six precingular plates, P. shumwayae comb. nov. also has a distinctive diamond or rectangular‐shaped anterior intercalary plate. Both Pfiesteria and Pseudopfiesteria gen. nov. are reassigned to the order Peridiniales based on an apical pore complex (APC) with a canal (X) plate that contacts a symmetrical 1′, four to five sulcal plates, and the conservative hypothecal tabulation of 5′′′, 0p, and 2′′′′. These morphological characters and the life histories of Pfiesteria and Pseudopfiesteria are consistent with placement of both genera in the Peridiniales. Based on the plate tabulations for P. shumwayae, P. piscicida, and the closely related “cryptoperidiniopsoid” and “lucy” groups, the family Pfiesteriaceae is amended to include species with the following tabulation: 4‐5′, 0‐2a, 5‐6′′, 6c, PC, 5+s, 5′′′, 0p, and 2′′′′ as well as an APC containing a pore plate (Po), a closing plate (cp), and an X plate; the tabulation is expanded to increase the number of sulcal plates and to include a new plate, the peduncle cover (PC) plate. Members of the family have typical dinoflagellate life cycles characterized by a biflagellated free‐living motile stage, a varying number of cyst stages, and the absence of multiple amoeboid stages.  相似文献   

19.
Impatiens pingxiangensis H. Y. Bi & S. X. Yu (Balsaminaceae), a new species from the limestone areas in Guangxi, China, is described and illustrated. The new species is similar to I. obesa in having succulent stems, subsessile peduncle, tufted pedicel and the lower petal in each pair of lateral united petals being connate, but differs from the latter by having perennial stems, leaf blades with 7–9 pairs of lateral veins, 1–2‐flowered racemes, ovate inner lateral sepals, and elliptic capsule. Moreover, the pollen and seed coat characters also support the recognition of the new species.  相似文献   

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