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1.
We describe fossil fruits collected from outcrops of the Salamanca Fm. (Paleocene, Danian, 63.3–61.9 Ma) at the Estancia Las Violetas locality, Chubut, Argentina that show affinities with members of the Subtribe Attaleinae, Tribe Cocoseae, Subfamily Arecoideae within the Arecaceae. The fossils are preserved as permineralizations, and were examined by longitudinal, tangential and cross-sections, as well as by the application of Computed Tomography Scanning technology (CT Scan). The fruits are ovoid drupes with 3 longitudinal grooves delimiting three valves; displaying apical stigmatic remains and a single apical germination pore. The exocarp and mesocarp are fused and anatomically indistinguishable one from another; they contain longitudinal fibrous bands with brachysclereids. A centrally placed seed occupies the single locule entirely; the seeds are deltoid with a basal hilum and acuminate tip while the endosperm is ruminate. The taxonomic position of the fossils was explored using phylogenetic analyses of molecular sequences combined with morphological data. Along with the suite of morphological characters that points to an affinity with the Subtribe Attaleinae, Tribe Cocoseae, subfamily Arecoideae, the results of the combined phylogenetic analyses confirm the taxonomic placement. This report constitutes the first confirmed record for the Subtribe Attaleinae worldwide and the first record of fossil palm fruits from Argentina.  相似文献   

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革苞菊属的分类及其地理分布   总被引:4,自引:0,他引:4  
研究认为卵叶革苞菊是一个独立种。因此,革苞菊属包含了2个种。革苞菊为北阿拉善一东戈壁分布种,卵叶革苞菊为南阿拉善东部(桌子山-贺兰山)低山丘陵分布种,二者形成明显的替代分布格局。该属为阿拉善荒漠特有属,亦为蒙古高原特有属。  相似文献   

4.
楼梯草属植物的瘦果具有较高的形态多样性,可作为种类鉴定的重要依据.然而,中国超过半数楼梯草属植物缺少瘦果形态信息.该研究通过野外考察、标本查阅以及光镜和扫描电镜的观察,对七种楼梯草属植物的瘦果进行了补充描述,并提供了墨线图和照片.该研究结果对该属的进一步分类修订提供了有价值的信息.  相似文献   

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Antichthomysis notidana n.g. n. sp. belonging to the Tribe Leptomysini is described from the coastal waters of south-eastern Tasmania. The genus is at present monospecific.  相似文献   

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应用光镜和扫描电镜对山东菊科莴苣亚族11属18种、1变种植物的花粉形态进行了观察研究。结果表明:莴苣亚族植物的花粉呈球形,具3~4沟孔,花粉表面具有网状纹饰,粗网眼15~21个,网脊上具1行刺,属于蒲公英(Taraxacum)型,与已报道的莴苣亚族其它属种的花粉形态相一致。通过莴苣亚族属间花粉形态的比较,认为花粉形态在属间分类上意义不大。  相似文献   

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The genus Oreocharis as circumscribed here consists of 27 species including 5 varieties, of which 5 species and 4 varieties are described as new in the present paper. In the work analysed were the external morphology and geographic distribution and examined under SEM were pollen exine of 22 species and seed coat of 16 species. As a result, three types of the corolla, two types of the anther, three types of the pollen exine and three types of the seed coat are distinguished here in the paper. It is discovered that the corolla in the genus is relatively stable, though diverse, and highly correlated with the characters of pollen grains and seeds. The corolla clearly bilabiate but constricted at the throat, occurring in O. auricula, O. cordatula, O. aurantiaca, etc., for an example, is correlated with smooth, reticulate pollen exine and partial tectum and the reticulate and smooth seed coat. For this reason the subdivision of the genus in the paper is mainly based on the characters of the corolla, but combined with those of the anther, pollen and seed coat. The genus is divided into four sections in the present classification. Dasydesmus Craib, based on a single species. O. bodinieri, is reduced here, and the reasons are given. The genus is distributed mainly in the subtropics, and less frequently in the tropics, of China south of 32.5°N and east of 98.5°E, with only two species beyond the border, O. hirsuta in Thailand (only a single locality in Chiengmai) and O. aurea also found in north Vietnam (see Fig. 1, Table 3). Sect. 1. Stomactin (Clarke) Fritsch. Corolla urceolate-tubular, constricted at the throat, with limb distinctly bilabiate; anthers broad-oblong; seed coat reticulate, smooth, rarely minutely tuberculate; pollen exine fine-reticulate, tectum partial and smooth, luminae slightly unequal in size. Sect. 2. Orthanthera K. Y. Pan Corolla campanulate or campanulate-tubular; anthers broad-oblong; seed coat reticulate, muri smooth, rarely spiny-processed; pollen exine fine-reticulate, with partial and smooth tectum and luminae slightly unequal in size, rarely exine insular and fine-tuberculate, tectum perforate. Setc. 3. Oreocharis Corolla thin-tubular; anthers broad-oblong; seed coat densely spinyprocessed, rarely fine-tuberculate; pollen exine insular, densely spiny-processed, rarely finereticulate and smooth, luminae unequal in size. Sect. 4. Platyanthera K. Y. Pan Corolla campanulate; anthers hippocrepiform; seed coat densely spiny-processed; pollen exine fine-reticulate, tectum perforate, luminae small, nearly equal in size. In the section Stomactin, although the constriction of corolla at its throat is a specialized character, the characters of seed coat, pollen grains and anthers are apparently primitive. Therefore it may be said at least that more primitive characters are preserved in the section. In the section Oreocharis, on the contrary, the characters of corolla, seed coat and pollen exine are all advanced. And in the section Platyanthera, the seed coat, pollen (with perforate tectum) and anthers have developed rather specialized characters.  相似文献   

12.
After having examined all specimens of the genus Prenanthes L. of Compositae in the Herbarium of Institute of Botany, Academia Sinica, I find that the classic concept on the genus Prenanthes established by G. Bentham in 1873 has not been held exactly by some of European, American, Japanese and Chinese botanists. For example, W. B. Hemsley, S. T. Dunn, A. Franchet, S. Kitamura and C. C. Chang placed plants from China which belong to other groups into the genus; I also find that the classic concept of the genus is not clear. The present paper makes a revision not only on the classic concept of the genus, but also on its concept assumed by the above-mentionded botanists. With the combination of numerous (25-35), white or yellow ligular florets, numerous ribs of achenes, Prenanthes alba L. (Nabalus albus (L.) Shih, comb. nov.) is distinctly different from Prenanthes purpurea L., which has the combination of purple, few (5-15) ligular florests and few ribs of achenes. Nabalus Cass., as a genus established early (1825) by H. Cassini, should be restored. It is not reasonable to treat Nabalus as a subgenus (E. B. Babcock et al. 1947) or a section (S. Kitamura, 1956) or as a synonym (G. Bentham, 1983) of the genus Preanathes L. The present author recognizes seven species in the new revised genus Prenanthes L. in China, 4 of which are described as new. In the genus Nabalus Cass. only one species, N. ochroleuca Maxim., is distributed in Northeast China. As Lactuca melanantha Franch. (1895), Prenanthes henryi Dunn (1903), P. glandulosa Dunn (1903), Lactuca triflora Hemsl. (1888) (it was transferred to Prenanthes L. by C. C. Chang in 1934), Prenanthes formosana Kitam. (1934) and P. wilsoni Chang (1934) all have campanulate involucres, purple phyllaries, purple dorsi-ventrally compressed achenes, longitudinal rids 6-9 on each side of achene truncate and beakless at its apex and pilose tubes of corollae, they should be placed neither into the genus Prenanthes with obtusely tri-or pentagonous, subterete achenes and glabrous tubes of corollae, nor into the genus Lactuca with beak achenes. Besides the above-mentioned species misnamed by some of foreign and Chinese botanists, 6 other species also have the same structure in achenes and corollae. Evidently, they fall into a new genus with the name Notoseris Shih. The new genus Notoseris Shih of the tribe Lactuceae of Compositae seems to be more reminiscent of Lactuca L. than of Prenanthes L. emend. All the 12 species of the genus Notoseris Shih are endemic to China and distributed in the area of south of Yantze River. Of them 6 are new combinations and 6 are described as new.  相似文献   

13.
Pierre Teilhard de Chardin was a French Jesuit paleontologist, priest, and philosopher. In the figures published in articles in 1943 and 1951, he attempted to draw a “plausible schematic reconstruction of the natural connections between fossil men” and a “phyletic composition of the human group”. I draw attention to Teilhard's reference to Eoanthropus (“Piltdown Man”) in small print in his figure that was first printed in 1943. Most suspiciously, there is no reference to this (supposedly important) genus in the associated text, nor is there any reference whatsoever to “Piltdown Man” in the article published in 1951. Even as early as January 1913, Teilhard may have been aware that “Piltdown Man” was a hoax or joke, artificially associating a human cranium with a modified orangutan mandible. A new suspect is Edgar Willett (rather than Charles Dawson). Teilhard may have been an advisory accomplice in a joke that went seriously wrong.  相似文献   

14.
报道了发现于山东的中国菊科新归化属种——史库菊属(Schkuhria Roth)和史库菊(Schkuhria pinnata(Lam.)Kuntze ex Thell.)。该种的主要特征为:叶片羽状全裂,裂片狭条形;总苞狭倒卵形;舌状花1~2枚或无,雌性;管状花4~8枚,两性;瘦果倒四棱锥形,鳞片状冠毛常8枚。提供了史库菊的彩色图片,简要介绍了该属的分布、史库菊的应用价值及入侵风险。  相似文献   

15.
该文报道了中国唇形科植物一新归化种——荆芥叶狮耳草[Leonotis nepetifolia(L.)R.Br.],该种的发现代表狮耳草属[Leonotis(Pers.)R.Br.]在中国的新归化。狮耳草属的主要特征为轮伞花序腋生,苞片和萼齿顶端针刺状,花冠桔红色或黄色,冠唇上唇较大,下唇较小;其与绣球防风属(Leucas R.Br)较为接近,但后者的萼齿等大,花冠通常白色,花冠筒不超出萼外,冠檐下唇长于上唇,二者区别较为显著。荆芥叶狮耳草为一年生草本。轮伞花序球形,多花密集,其下承以多数密集苞片;苞片细长,向下微弯曲,先端针刺状。花萼管状,先端膨大而略折曲;萼齿针刺状,最上面一枚较大。花冠桔红色,密被桔红色绒毛;花冠筒细长,伸出萼筒之外;冠檐二唇形,上唇较大,下唇较小。荆芥叶狮耳草与同属植物Leonotis leonurus R.Br.最为相似,但前者叶为卵圆形或心形,后者的叶片多为披针形。根据该研究的标本和相关文献资料,该文还提供了狮耳草属和荆芥叶狮耳草的形态描述、地理分布的讨论,以及荆芥叶狮耳草的资源价值、归化途经、繁殖和危害的讨论和野外生态照片。  相似文献   

16.
An earlier article described the mid-twentieth century origins of the method of “paradigms” in paleobiology, as a way of making testable hypotheses about the functional morphology of extinct organisms. The present article describes the use of “paradigms” through the 1970s and, briefly, to the end of the century. After I had proposed the paradigm method to help interpret the ecological history of brachiopods, my students developed it in relation to that and other invertebrate phyla, notably in Euan Clarkson’s analysis of vision in trilobites. David Raup’s computer-aided “theoretical morphology” was then combined with my functional or adaptive emphasis, in Adolf Seilacher’s tripartite “constructional morphology.” Stephen Jay Gould, who had strongly endorsed the method, later switched to criticizing the “adaptationist program” he claimed it embodied. Although the explicit use of paradigms in paleobiology had declined by the end of the century, the method was tacitly subsumed into functional morphology as “biomechanics.”  相似文献   

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报道了发现于山东的中国菊科新归化属种——史库菊属(Schkuhria Roth)和史库菊(Schkuhria pinnata(Lam.) Kuntze ex Thell.)。该种的主要特征为:叶片羽状全裂,裂片狭条形;总苞狭倒卵形;舌状花1~2枚或无,雌性;管状花4~8枚,两性;瘦果倒四棱锥形,鳞片状冠毛常8枚。提供了史库菊的彩色图片,简要介绍了该属的分布、史库菊的应用价值及入侵风险。  相似文献   

18.
树舌亚属是灵芝属(Ganoderma)的重要组成部分。因许多分类学家对这一类群真菌的分类有不同的处理,所以对它的分类地位时有变动。全面论述这一类群真菌的著作也比较少。现作者比较详细地研究了中国的本亚属标本,综合各国专家历年的论著,对于它的历史与分类地位,宏观与微观特性以及亚属的范围作了比较全面的论述。并有亚属描述和中国已知种检索表。另外报道了2新种(Ganoderma meijiangense Zhao sp.nov.;G.shangsienseZhao sp.nov.),1中国新记录和1疑问种。全部研究标本都保藏于中国科学院微生物研究所真菌标本室。  相似文献   

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Lindenius paleomystax” described from the Miocene Dominican amber has been included into a separate digger wasp genus, Lindocerus gen. nov. (Crabronidae, Crabroninae, Crabronini), which is similar to the genus Crossocerus Lepeletier de Saint Fargeau et Brullé, 1835, but differs in the well-pronounced hypersternaulus.  相似文献   

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Surface and transverse section achene structures ofBolboschoenus maritimus, B. robustus, B. fluviatilis, B. novae-angliae, B. glaucus, and the putative hybridsB. maritimus × B. rubustus andB. glaucus × B. maritimus from North America are described and illustrated with SEM micrographs. The same three type of pericarp structure reported by Browning and Gordon-Gray (1993) from southern Africa were found except that the “type 2” (B. glaucus) was not matched precisely. Intermediate achene structures and other evidence support both the hybrid origin ofB. novae-angliae (=B. fluviatilis × B. robustus) and hybridization betweenB. glaucus andB. maritimus. The new combinationBolboschoenus novae-angliae is made.  相似文献   

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