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1.
The genus Macrorungia C. B. Clarke is revised. 5 taxa have previously been proposed in the genus; the present revision recognises 3, viz. Macrorungia galpinii C. Baden sp. nov., M. longistrobus C. B. Clarke and M. pubinervia (T. Anders.) C. B. Clarke. The delimitation between Anisotes and Macrorungia is discussed. Phytogeographical and ecological aspects are discussed in relation to the phytogeog–raphical division of Africa.  相似文献   

2.
Diagnoses of three new species and three new subspecies of Anisotes are presented together with those of six subgeneric taxa.  相似文献   

3.
The characters that define the genus Kailarsenia (Rubiaceae), namely the stipule morphology, seed-coat perimeter thickening and colporate pollen, are entirely consistent with the morphology of three Australian species placed in that genus. A preliminary cladistic analysis of the genus indicates that the Queensland species K. ochreata and K. jardinei are more closely related to the Bornean K. campanula than to K. suffruticosa an endemic of the Northern Territory, Australia. Kailarsenia suffruticosa has its affinities with the type of the genus K. tentaculata and K. lineata of tropical Asia. The recently described genus, Larsenaikia is reduced to synonomy.  相似文献   

4.
An aberrant species of the genus Asteriscus (Asteraceae–Inuleae), A. pinifolius from SW Morocco, is here proposed to be removed and placed in a separate, monotypic genus Ighermia. The systematic position and morphology of the new genus are also discussed.  相似文献   

5.
Artem Y. Sinev 《Hydrobiologia》2004,520(1-3):29-47
The little-known cladoceran Alona macrocopa Sars, 1894 and four related species differ from the majority of the genus Alona by unusual morphology of antenna and postabdomen. Only two species of the five, A. macrocopa Sars, 1894 and A. imitatoria Smirnov, 1989, are found to be valid. The species A. abbreviata Sars, 1895, A. duodontha Henry, 1922 and A. guernei Smirnov, 2001 are proved to be the synonims of A. macrocopa. The detailed morphology of appendages of A. macrocopa and A. imitatoria is studied for the first time. Analysis of morphology of the macrocopa-group reveals numerous characters clearly separating it from other species of Alona despite the wide diversity of this genus. Unusual morphology of the antenna, and the female and male postabdomen does not allow placement of the macrocopa-group in any other genera of Aloninae. So the new genus Armatalona gen. n. is suggested. This new genus is the highly specialized marginal genus of Aloninae, closely related only to the Australian endemic genus Pseudomonospilus Smirnov, 2001. The morphology of Armatalona gen. n. and its place within Aloninae are discussed.  相似文献   

6.
In this study we show that morphological diversification in the avian genus Carduelis (Carduelinae) has to a large extent been conservative. Using multivariate methods, we found only minor deviations from the common (ancestral) body-plan. In particular, variation in bill morphology was found to be more conservative than variation in other parts of the body. We argue that constraint models of population differentiation can successfully account for the variation in bill morphology in this genus, but are less successful in accounting for variation in other traits. This can be interpreted as a result of long-term overall stabilizing selection for a certain bill morphology which is related to the way the birds open seeds. A trait combination that is adaptive on the evolutionary time scale may thus act as a constraint on changes in bill morphology on the microevolutionary scale. We conclude that the most parsimonious explanation for low divergence in bill morphology in this genus is that all species have retained the ancestral bill morphology. This may mean that each species chooses its environment rather than being moulded by it. This argument seems to apply to bill morphology, but other traits studied in this genus appear to have evolved in a less constrained fashion. A new index of morphometric integration is introduced to describe covariance structures.  相似文献   

7.
A detailed morphological and anatomical study of the tropical African genus Virectaria is presented. The observations are used to characterize the genus, to propose a key to all eight species, and to unravel the relationships between the species using cladistics. A taxonomic survey of the genus is also given. Verdcourt's infraspecific taxa based on calyx morphology in V major are adopted, but it was found that morphological distinction is correlated with ecological, habit and distributional differences. Hence, it is better to recognize Verdcourt's varieties spathulata and major as subspecies of V. major. The problematic systematic position of the genus is discussed in detail. New evidence is given for the exclusion of the genus from the Hedyotideae and Ophiorrhizeae (subfamily Rubioideae). The recently proposed position in the Sabiceeae (subfamily Ixoroideae) is not convincing either, since none of the genera included in the Sabiceeae matches Virectaria with respect to pollen, fruit, flower and growth habit. Exclusion from the Rubioideae and a position near the Sabiceeae is supported by lack of raphides, seed anatomy, placentation, stipule morphology and molecular evidence. Molecular data from a larger number of taxa are needed to confirm the position of the genus.  相似文献   

8.
Hannah Banks  Lourdes Rico 《Grana》2013,52(5):261-276
The diverse pollen morphology of fourteen species of the genus Eperua is described and illustrated using light, scanning electron and transmission electron microscopy. Six pollen types are described and a key for their identification is provided. A cladistic analysis was carried out using macromorphological and palynological characters to form a hypothesis of relationships between taxa. The pollen morphology is discussed with regard to systematic relationships, function and phylogenetic significance of certain pollen morphological structures within the genus.  相似文献   

9.
A monotypic new genus,Harleyodendron, is described from the relict coastal rainforest of eastern Brazil. Gross morphology, wood and leaf anatomy, and pollen morphology are considered.  相似文献   

10.
若干悬钩子属植物的花粉形态研究   总被引:7,自引:0,他引:7  
陈少风  叶居新 《植物研究》1996,16(4):463-466
蔷微科悬钩子属10种植物的花粉形态进行了扫描电镜观察,描述了花粉形态的特征,探讨了植物花粉形态特征与外部形态特征的关系。  相似文献   

11.
12.
Anderberg, A. A. & Karis, P. O. 1995. Psednotrichia , a genus of the tribe Senecioneae hitherto misplaced in the Astereae (Asteraceae). — Nord. J. Bot. 15: 375–379. Copenhagen. ISSN 0107–055X.
The tribal position for the little known genus Psednorrichia , is established. This monotypic genus, hitherto placed in the tribe Astereae, is a congener of Xyridopsis of the tribe Senecioneae (Asteraceae). The two species of Xyridopsis are here transferred to Psednotrichia and the new combinations P. xyridopsis and P. newtonii are made. A brief discussion of the morphology of the genus, and its systematic position within the tribe Senecioneae is provided.  相似文献   

13.
A species of the genus Tupistra,T.pingbianensis J.L.Huang et X.Z.Liu,is described as new,and its karyotype and pollen morphology are reported. The bimodal karyotype of this species is formulated as 2n=38=14m+10sm+8st+6t,and pollen grains are spheroidal,inaperturate,with rugulate exine sculpture.Based on its floral structure,karyotype and pollen morphology,T.pingbianensis J.L.Huang et X.Z.Liu is considered phylogenetically closely related to T.fungilliformis Wang et Liang.Whether the repense rhizome,solitary leaves of T.pingbianensis J.L.Huang et X.Z.Liu indicate a close relationship between the genus Tupistra and the genus Aspidistra needs further studies.  相似文献   

14.
An account is given of the morphology and the taxonomy of the Asian, Australian and Pacific genus Archidendron (Leguminosae – Mimosoideae). A new infrageneric classification based on morphological data is presented, the genus being subdivided in 8 series. The phylogeny of the genus is discussed, the base of discussion being all available morphological, palynological and wood–anatomical characters. The presence/absence of stipules, the length of the staminal tube compared with that of the corolla–tube, the sessile/stipitate ovary(–ies), the morphology of the pods and the wood–anatomy have been particularly useful in determining the evolutionary trends within the genus. Analyses of the geographical range of selected character states are presented. The data suggest a Central – W. Malesian origin of the genus. The series endemic to the E. Malesian – Australian area have probably evolved more recently. The pluricarpellate condition of the flowers in several species endemic to the E. Malesian and Australian area is considered to be a derived character state. The following new taxa are proposed: Ser. Calycinae Nielsen, ser. Ptenopae Nielsen, ser. Bellae Nielsen, Archidendron falcatum Nielsen, A. cockburnii Nielsen, A. sabahense Nielsen, A. fagifolium (Bl. ex Miq.) Nielsen var. borneense Nielsen, A. kunsrteri (Prain) Nielsen subsp. ashtonii Nielsen, A. ellipticum (Bl.) Nielsen subsp. cordifoliolatum Nielsen. New combinations are proposed in the Malesian species formerly referred to Abarema, Zygia and Morolobium by Kostermans. Keys to and an enumeration of the species are presented.  相似文献   

15.
An account is given of the morphology and the taxonomy of the Asian, Australian and Pacific genus Archidendron (Leguminosae - Mimosoideae). A new infrageneric classification based on morphological data is presented, the genus being subdivided in 8 series. The phylogeny of the genus is discussed, the base of discussion being all available morphological, palynological and wood-anatomical characters. The presence/absence of stipules, the length of the staminal tube compared with that of the corolla-tube, the sessile/stipitate ovary(-ies), the morphology of the pods and the wood-anatomy have been particularly useful in determining the evolutionary trends within the genus. Analyses of the geographical range of selected character states are presented. The data suggest a Central - W. Malesian origin of the genus. The series endemic to the E. Malesian - Australian area have probably evolved more recently. The pluricarpellate condition of the flowers in several species endemic to the E. Malesian and Australian area is considered to be a derived character state. The following new taxa are proposed: Ser. Calycinae Nielsen, ser. Ptenopae Nielsen, ser. Bellae Nielsen, Archidendron falcatum Nielsen, A. cockburnii Nielsen, A. sabahense Nielsen, A. fagifolium (Bl. ex Miq.) Nielsen var. borneense Nielsen, A. kunstleri (Prain) Nielsen subsp. ashtonii Nielsen, A. ellipticum (Bl.) Nielsen subsp. cordifoliolatum Nielsen. New combinations are proposed in the Malesian species formerly referred to Abarema, Zygia and Morolobium by Kostermans. Keys to and an enumeration of the species are presented.  相似文献   

16.
开口箭属一新种及其核型和花粉形态   总被引:1,自引:0,他引:1  
文章报道了新种屏边开口箭T.pingbianensis J.L.Huang et X.Z.Liu及其核型和花粉形态。屏边开口箭的核型公式为2n=38=14m+lOsm+8st+6t,具明显的二型性,属3C型。花粉粒为球形,无萌发孔沟,外壁具皱块状纹饰。从花结构、核型和花粉形态上看,屏边开口箭和伞柱开口箭T.fungilliformis Wang et Liang亲缘关系近,而且伞柱开口箭比屏边开口箭在一系列特征上都较特化。  相似文献   

17.
本文对中国东北牛儿苗科(Geraniaceae)二属(太阳花属Erodium, 老鹳草属(Geranium)计14种(species)1变种(Variety)和1变型(form)植物的种皮亚显微结构(SEM)及种子形态进行了研究.结果表明, 太阳花属与老鹳草属植物无论从种子形状, 长宽比, 还是种皮初级雕纹及次级雕纹形态都表现出明显差异。在老鹤草属下种及种下等级的鉴定和划分上, 种皮微形态及种子形态特征提供了大量有价值的信息。  相似文献   

18.
WIKLUND, A., 1986. The genus Rhanterium (Aateraceae: Inuleae) . This revision of the genus Rhanterium Desf. of the /nu/a-group in the Asteraceae: Inuleae, subtribe Inulinae, is based on studies of herbarium material. The genus is distributed over western North Africa, the Arabian peninsula, Iraq and Iran. Three species are recognized: R. adpressum Coss. & Durieu, R. epapposum Oliver and R. suaveolens Desf. A fourth previously accepted species, R. intermedium Coss. & Durieu ex Pomel, is here considered to be composed of hybrids between R. adpressum and R. suaveolens. A laxonomical recognition of these hybrids is not found to be justified. The morphology, phylogeny and phytogeography of the species are discussed and a cladogram of the genus is proposed.  相似文献   

19.
20.
ROMERO, G. A., 1992. Non-functional flowers in Catasetum orchids (Catasetinae, Orchidaceae). Plants of the genus Catasetum generally produce unisexual, dimorphic flowers but occasionally bear intermediate, polymorphic flowers. Staminate (male) flowers are commonly produced both in cultivation and in nature. Within the genus, the morphology, texture, resupination, and colour of male flowers are extremely variable. Pistillate (female) flowers, in contrast, are rarely produced in cultivation and in nature and have relatively constant morphology, texture, resupination and colour. Intermediate, polymorphic flowers are extremely rare, ranging in morphology from male-like to female-like, often combining characters of both. Some are bilaterally half male and half female. Intermediate flowers have previously been regarded as functionally hermaphroditic but evidence presented here shows that in Catasetum male and female functions appear to be mutually exclusive. Intermediate flowers that approach the morphology of female flowers may bear seeds but do not have functional pollinaria; those that approach male flower morphology do not have functional stigmas and seldom have functional pollinaria. The vast majority of Catasetum intermediate flowers are sterile. The absence of truly hermaphroditic flowers in Catasetum is important in the interpretation of evidence for gender choice in this genus, as flowers and/or plants can be unequivocally scored as either functionally male or female.  相似文献   

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