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1.
王文采  韦毅刚 《广西植物》2016,36(Z1):100-106
描述了在中国广西发现的楼梯草属五新种:小果楼梯草(Elatostema microcarpum W. T. Wang & Y. G. Wei)在体态方面与荔波楼梯草(E. liboense W. T. Wang)极为相似,但茎较低矮,不具软鳞片,叶上面无毛,钟乳体较小而可区别。圆序楼梯草(E. gyrocephalum W. T. Wang & Y. G. Wei)在体态上与浅齿楼梯草(E. crenatum W. T. Wang)相似,但叶两面均有糙伏毛,侧脉较少,4~6对,钟乳体较小,长约0.1 mm而不同。对序楼梯草(E. binatum W. T. Wang & Y. G. Wei)在亲缘关系方面与深绿楼梯草(E. atroviride W. T. Wang)相近,但茎和叶无毛,雄花序托较小,近方形,长度及宽度约6.5 mm,小苞片较小,长约1.5 mm,无毛,可以区别。河池楼梯草(E. hechiense W. T. Wang & Y. G. Wei)似华南楼梯草(E. balansae Gagnep.)但叶的渐尖头全缘,钟乳体较小,长0.1~0.15 mm,雌花序苞片顶端无角状突起,可以区别。环江楼梯草(E. huanjiangense W. T. Wang & Y. G. Wei)可能与樟叶楼梯草(E. petelotii Gagnep.)有亲缘关系,但后者的叶全缘,钟乳体较大,长0.3~0.7 mm,侧脉在狭侧3条,在宽侧4条,雌花序常有长花序梗,而与本种相区别。  相似文献   

2.
Four species of heath, occurring in the heathlands of Brittany, are compared regarding their water relations: Calluna vulgaris, Erica ciliaris, E. cinerea and E. tetralix. E. cinerea is unable to establish itself in wet heathland because of its intolerance of prolonged waterlogging. It is the Erica species best adapted to dry habitat conditions in Brittany. E. ciliaris canot establish itself in dry heathland and is less tolerant of waterlogging than E. tetralix. E. tetralix is the species best adapted to wet heathland, being tolerant of waterlogging, but can also establish itself in dry heathland. Of the three E. species it has the widest ecological range. Calluna is tolerant of both wet and dry conditions and has a wide ecological range. E. cinerea is typical of dry- and E. tetralix of wet heathland. Although both species did best in moist aerated soil in experimental cultures, neither is abundant in mesophilic heaths where E. ciliaris is dominant. One explanation may be competition for aerial space. E. cinerea and E. tetralix both have an upright growth, whereas E. ciliaris rapidly adopts a straggling bushy habit, with long rooting branches. E. ciliaris thus establishes large interpenetrating clumps. With increasing dryness E. ciliaris disappears and may be replaced by E. cinerea and, with increasing wetness and especially waterlogging, E. tetralix will take over.  相似文献   

3.
A systematic analysis of the variable and probably allotetraploidE. minima is presented, its infraspecific taxonomy is discussed.E. tatrae is provisionally included intoE. minima although some differences may exist;E. mendonçae may be a relic of a formerly wider distribution ofE. minima; E. willkommii seems to be closer toE. stricta s. lat. than toE. minima. 4x-E. minima is supposed to be derived from phylogenetic lines close to extant dwarf alpine forms of 2x-E. alpina (including its yellow flowering subsp.christii;Vitek 1985b) and 2x-E. hirtella (vgl.Vitek 1985a). Some characteristics (e.g., its small flowers) could have been introduced through hybrid introgression from other 2x-species, particularlyE. inopinata and/orE. sinuata (vgl.Ehrendorfer & Vitek 1984).  相似文献   

4.
王文采 《广西植物》2017,37(2):135-138
该文描述了自云南东南部发现的荨麻科楼梯草属二新种。(1)文山楼梯草,与上林楼梯草在亲缘关系上相近,与后者的区别在于本种的茎密被短柔毛,叶片在基部斜楔形,具半离基三出脉,雌头状花序的花序托较小,长约1.2 mm,宽1 mm,不分裂,其雌苞片约12,不等大,只3枚在顶端具角状突起。(2)绿突楼梯草,与马关楼梯草近缘,与后者的区别在于茎密被反曲的柔毛和贴伏的短柔毛,雄花序较长,雄总苞的苞片6枚,排成2层,2外层苞片较大,背面具1绿色纵列龙骨状突起和4或6绿纵肋,4内层苞片较小,背面近中央有1绿色角状突起。  相似文献   

5.
王文采 《广西植物》2016,36(Z1):152-155
该文描述了自云南东南部发现的荨麻科楼梯草属2新种。其中,文山楼梯草与上林楼梯草在亲缘关系上相近,与后者的区别在于本种的茎密被短柔毛,叶片在基部斜楔形,具半离基三出脉,雌头状花序的花序托较小,长约1.2 mm,宽1 mm,不分裂,其雌苞片约12,不等大,只3枚在顶端具角状突起。第二种,绿突楼梯草与马关楼梯草近缘,与后者的区别在于茎密被反曲的柔毛和贴伏的短柔毛,雄花序较长,雄总苞的苞片6枚,排成2层,2外层苞片较大,背面具1绿色纵列龙骨状突起和4或6绿纵肋,4内层苞片较小,背面近中央有1绿色角状突起。  相似文献   

6.
Three new species of Etamphidelus are described from Orange Bay, Hoste Island, Chile. All three are distinguished from previously described species by their numerous longitudinal cuticular ridges. E. acucephalus n. sp. is further distinguished by its extremely narrowed anterior body region and posteriorly situated amphids. E. fueguensis n. sp. is distinguished from E. acucephalus by its anteriorly located amphideal fovea, fewer cuticular ridges, smaller V-an/tail ratio and presence of males. E. yamani n. sp. is more similar to E. fueguensis n. sp. differing from it by a wider head end, more posteriorly located excretory pore, longer V-an/tail ratio, more numerous cuticular ridges and smaller spermatozoa. E. puccinelliae (Lorenzen, 1966) Andrássy, 1977 is transferred to Paramphidelus puccinelliae (Lorenzen, 1966) n. comb. The generic diagnosis of Etamphidelus is amended, and a key to species is presented.  相似文献   

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9.
Among the ascomycete isolates from soil and armadillo dung collected in São Paulo State, Brazil, a new species ofEmericella, E. montenegroi and a new variety ofE. rugulosa, E. rugulosa var.Iazulina are described and illustrated.Emericella montenegroi differs from the other known species of the genus in having ascospores with an incompletely reticulate or ribbed ornamentation on the convex walls.Emericella rugulosa var.Iazulina differs from the type variety in having blue to violet color of ascospores. Isolations ofE. corrugata andE. foveolata are also reported as a South American record. A synoptic key to all accepted species of the genus is provided.  相似文献   

10.
Entomophthora brevinucleata, a fungal pathogen of gall midges, is described. The species occurs on at least 3 host species, including the wheat blossom midgeSitodiplosis mosellana Géhin andMycodiplosis sp.E. brevinucleata produces rhizoids, either monohyphal or comprising bundles of a few hyphae, without holdfasts. The hyphal bodies are subspherical with mean dimensions of 27.5×22.1 μm. The primary conidia are campanulate with mean dimensions from individual hosts of 11.2–18.9×8.7–15.8 μm. They contain 3–13 nuclei with a mean diameter of between 2.7 and 3.7 μm stained with lactophenol-aceto-orcein. The secondary conidia are of similar shape but smaller. Cystidia and resting spores were not observed.  相似文献   

11.
The essential oils of the leaves of Eugenia acutata, Eugenia candolleana, Eugenia copacabanensis and Myrcia splendens (Myrtaceae) from Brazil’s southeastern Atlantic Forest were obtained by hydrodistillation and analyzed by GC–MS. Oxygenated sesquiterpenes were predominant in E. copacabanensis (54.3%) and E. candolleana (50.9%) whilst hydrocarbon species predominated in E. acutata (83.4%) and M. splendens (94.5%). trans-Caryophyllene was the most abundant component in E. acutata. Isomers of guaiol and cadinol alcohols, followed by δ-elemene and viridiflorene, were the major components of the essential oil of the leaves of E. candolleana. Hydrocarbons and alcohols of the cadinane-type predominated in E. copacabanensis the most abundant being epi-cubenol (14%). M. splendens had 80% α-bisabolene in the leaf oil along with <5% β-farnesene. Additionally, E. copacabanensis exhibited 13.7% monoterpenes. Whereas the bisabolene-rich M. splendens oil is highly similar to that of other Myrcia species reported elsewhere, the Eugenia species oils corroborated the complex array and differing abundances of terpene classes within this genus. This study generated data which may provide further comprehension of the phylogenetic relationships between Myrtaceae genera and species.  相似文献   

12.
Chaperone GroEL/GroES and Lon protease were shown to play a role in regulating the expression of the Vibrio fischeri lux operon cloned in Escherichia coli cells. The E. coli groE mutant carrying a plasmid with the full-length V. fischeri lux regulon showed a decreased bioluminescence. The bioluminescence intensity was high in E. coli cells with mutant lonA and the same plasmid. Bioluminescence induction curves lacked the lag period characteristic of lon + strains. Regulatory luxR of V. fischeri was cloned in pGEX-KG to produce the hybrid gene GST-luxR. The product of its expression, GST-LuxR, was isolated together with GroEL and Lon upon affinity chromatography on a column with glutathione-agarose, suggesting complexation of LuxR with these proteins. It was assumed that GroEL/GroES is involved in LuxR folding, while Lon protease degrades LuxR before its folding into an active globule or after denaturation.  相似文献   

13.
Strain Z-M001 of a unicellular cyanobacterium, assigned by analysis of the 16S rRNA gene sequence to the phylogenetic group of the generic level Euhalothece, was isolated from soda Lake Magadi. It was shown that strain Z-M001, unlike all other known cultured and uncultured organisms of the Euhalothece group, is extremely natronophilic, and it was named accordingly “Euhalothece natronophila”. In its ecophysiological characteristics, it is comparable to extremely alkaliphilic organotrophic natronobacteria, which is essential for soda ecosystems, because cyanobacteria belong to primary producers. E. natronophila exhibits considerable morphological variability depending on the concentration of carbonates in the medium. The polymorphism of “ E. natronophila” is primarily connected to limitation by utilizable forms of carbon.  相似文献   

14.
The diploid Emila sonchifolia (2n = 10) and the tetraploid E. fosbergii (2n = 20) species are widely distributed throughout tropical and subtropical America, and are the only two Emilia species occurring in Brazil. Emilia fosbergii displays two sets of ten chromosomes, one slightly larger than the other. The smaller chromosome set is similar to the chromosome complement of the diploid, which agrees with the suggested participation of E. sonchifolia in the formation of E. fosbergii. To elucidate this hypothesis, the relationship between the genomes of the two species was investigated using chromomycin A3 (CMA)/4’,6-diamidino-2-phenylindole (DAPI) double staining, distribution of 5S and 45S rDNA sites by fluorescence in situ hybridization (FISH) and whole genome comparison by genomic in situ hybridization (GISH). CMA/DAPI staining and FISH revealed the occurrence of one pair of CMA bands in E. sonchifolia and three pairs in E. fosbergii, all of them co-localized with 45S rDNA sites. Additionally, E. fosbergii displayed a fourth, small 45S rDNA site in its larger subgenome which was not detected as CMA band. Surprisingly, the euchromatin of the smaller subgenome of E. fosbergii stained less intensely with CMA than the larger one. The GISH procedure demonstrated the similarity between the genome of E. sonchifolia and the smaller chromosome set of E. fosbergii. GISH and CMA staining clearly demonstrate that E. fosbergii is an allotetraploid species and suggest E. sonchifolia as one of its ancestors. The maintenance of at least one pair of 5S and 45S rDNA sites per subgenome of E. fosbergii and the differentiation between its subgenomes by CMA staining seem to indicate that post-polyploidization changes are still incipient, probably because the polyploidization event and the origin of E. fosbergii were relatively recent.  相似文献   

15.
Peter Lesica 《Brittonia》2005,57(1):47-54
Erigeron parryi was described in 1890 from a single collection from southwest Montana. No additional collections were made during the following 90 years. Recent floristic treatments have synonomized E. parryi under E. ochroleucus. I used principal components and discriminant analyses of morphological characters to examine the relationship of E. parryi to its presumed closest relatives, E. ochroleucus, E. radicatus, and E. scribneri, in light of several populations discovered in the past 20 years. Erigeron parryi should be considered a distinct species. It can be readily distinguished from closely related species based on indument and caudex morphology. It is allopatric with E. ochroleucus and E. scribneri and ecologically separated from E. radicatus. Erigeron scribneri is intermediate between E. ochroleucus and E. radicatus and is probably best treated as a variety of one or the other of these species.  相似文献   

16.
报道了卫矛属(Euonymus)一新变种——腥臭卫矛(Euonymus sanguineus var.paedidus L.M.Wang)。该新变种与原变种石枣子(Euonymus sanguineus Loes.var.sanguineus)相似,但其独特的强烈腥臭花不仅明显可与石枣子区别,而且也有别于卫矛属中所有其他种类。另外,该变种叶柄极短,一般短于5mm,可以与原变种区别。对腥臭卫矛的分布与生境做了简略讨论。  相似文献   

17.
王文采 《广西植物》2019,39(3):291-293
描述了自重庆南部发现的荨麻科楼梯草一新种,江津楼梯草(Elatostema jiangjinense)。此新种与锐齿楼梯草(E. cyrtandrifolium)近缘,两者的区别在于江津楼梯草的叶在狭侧具2条二级脉,托叶卵形或披针形,以及雄总苞片在顶端具长角状突起。  相似文献   

18.
A new species of the fungus weevil genus Glaesotropis is described from the Late Eocene Rovno amber. G. diadiasashai sp. nov. differs from G. weitschati and G. minor described from Baltic amber in having a longer rostrum and in the structure of its antennae, with the third and fourth antennomeres being longer than the first and second ones. Additionally, the new species differs from G. weitschati in being smaller, in having unswollen frons, and weakly and smoothly concave elytral margin near hind coxae. The new species also differs from G. minor in having an uninterrupted posterior transverse carina on the pronotum, elytra less convex longitudinally, and a slightly broadened rostrum at the attachment of antennae.  相似文献   

19.
A new emmelichthyid,Erythrocles microceps, is described from 15 specimens collected in Mimase Fish Market and Tosa Bay, Kochi Prefecture, Japan. It differs from its most similar congener,E. acarina, in having a greater number of lateral line scales (70–72 vs. 62–67 inacarina), more elongate body (body depth 23.8–25.9% SL vs. 27–29% SL), and smaller head (head) length 26.8–28.4% SL vs. 34–36% SL).  相似文献   

20.
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