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1.
The two species ofPeratanthe, a genus allegedly endemic to the greater Antilles, are shown to be entirely within the variation range ofNertera granadensis (L.f.) Druce var.granadensis, a widespread, often weedy species.  相似文献   

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Bryosedgwickia is considered a synonym ofPlatygyriella and the following transfers are proposed:P. aurea, P. aureoides, P. densa, P. fragilifolia, P. kirtikarii andP. pringlei. A key is provided to the accepted species ofPlatygyriella. Excluded species are treated asHondaella entodontea (C. Müll.) Buck andIsopterygium jamaicense (Bartr.) Buck.  相似文献   

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Synopsis Evidence is presented which suggests that the nonparasitic lamprey, Lampetra (Eudontomyzon) gracilis Kux, 1965, is conspecific with the parasitic lamprey Eudontomyzon danfordi Regan, 1911. The diagnostic characters of the holotype and of the non-type material of E. gracilis are features found in E. danfordi specimens in their second and final year of adult life, thereby making the former a junior synonym of the latter.  相似文献   

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根据对广东木莲Manglientia kwangtungensis(Merr.)Dandy和毛桃木莲M.moto Dandy大量标本的研究,将毛桃木莲处理为广东木莲的一个异名。  相似文献   

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The phylogeny of Gardenieae (Rubiaceae) is evaluated using 70 morphological and anatomical characters and 81 terminal taxa. After successive reweighting of the characters and modified bootstrap tests the following is concluded. The position of the Diplosporinae genera Argocoffeopsis, Calycosiphonia, Cremaspora and Tricalysia with the genera belonging to the tribes Aulacocalyceae, Coffeeae, Octotropideae and Pavetteae, suggests that this subtribe does not belong in Gardenieae. Posoqueria is nested among outgroup genera and consequently is not a member of the tribe. Robbrecht & Puff's informal 'tetrad group' is monophyletic. Likewise, their 'Alibertia group' is supported as monophyletic, although slightly rearranged. On the other hand, their 'Aidia group' must he greatly expanded with several genera in order to be monophyletic, but the monophyly of this group is weakly supported. Several disputed genera should be included in Gardenieae ( Anomanthodia, Amaioua, Brachytome , and supposedly Bertiera ). Most inferred groups, however, exhibit low bootstrap values and should he viewed with caution.  相似文献   

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Occurrence of secondary pollen presentation (SPP) is evidenced for Duperrea pavettifolia. For this, self-pollen was presented on the stigma and reduced fertilization was observed in this case. The receptive area located in the furrow of the stigma becomes receptive from the third day of elongation growth. Fruit set upon hand pollination with pollen from other individuals was significantly higher than the results of selfed, bagged, emasculated and control treatments. However there was no difference in pollen tube growth rate between selfed and crossed pollen on a receptive stigma. Hawkmoths and butterflies were effective pollinators for D. pavettifolia, but the visiting frequencies were very low. Stingless bees removed pollen from the unreceptive stigma which had no contribution to reproductive success. High level of outcrossing in D. pavettifolia was demonstrated by molecular analyses using the simple sequence repeats (SSR) method. Although the wild populations of D. pavettifolia are small and with fragmented distribution, the genetic diversity of seedlings was high, with fluctuations among years. Our results indicated that protandry and the visitation of stingless bees reduced the amount of self-pollen on the still unreceptive stigma and self-incompatibility prevented fertilization by un-removed self-pollen.  相似文献   

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Pedicularis cyathophylla Franchet in Bull.Soc.Bot.France 47:25.1900.Type:China.Sichuan:Kangding,Zheduoshan Mountains (Ta-tsien-kou & Tche-to-chan),J.A.Soulié 218 (holotype,P00160827,P!).Pedicularis xiangchengensis H.P.Yang in Acta Phytotax.Sin.28:137.f.3:3.1990,syn.nov.Type:China.Sichuan:Xiangcheng,Rewu,on mountain slopes,alt.4100-4300 m,1981-08-06,Qing-Zang Exped.3829(holotype,00032964,PE!;isotypes,KUN!,CDBI!).  相似文献   

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直立百部的一个新异名   总被引:1,自引:0,他引:1  
根据对直立百部Stemona sessilifolia(Miq.)Miq.大量标本的研究和野外调查及引种栽培观察,结合对山东百部Stemona shandongensis D.K.Zang模式标本产地的调查,发现直立百部的形态性状是多变的。研究表明它的习性受生境影响而多变,从直立半灌木到蔓生都有;叶型多变;花通常出自叶腋,而花梗有时与叶柄,甚至主脉合生;内轮花被片大多明显大于外轮。山东百部的形态性状处于直立百部的变异范围内,因此作为独立的种是难以成立的,应处理为直立百部的新异名。  相似文献   

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Hedyotis salzmannii (Rubiaceae) is distylous. Experimental pollination revealed that both morphs are self-compatible. However, the thrum morph proved to be more self-compatible. Hand cross-pollination between different plants of the same floral form produced less seed-sets per pollination than hand cross-pollination between pin and thrum or thrum and pin pollination. Two species ofHymenoptera, oneApidae and oneHalictidae, and two species ofDiptera (Syrphidae) were observed as pollinators.  相似文献   

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All neotropical genera previously included in the tribe Isertieae A. Rich. ex DC. are considered. The tribe Isertieae is here delimited by the following characters: absence of rhaphides, valvate aestivation of the corolla, cordiform or discoid placenta, fleshy indehiscent fruit, and seed coat cells with pitted walls. As so delimited, the tribe definitely includes the neotropical generaIsertia Schreb.,Gonzalagunia Ruiz & Pav.,Amphidasya Standl.,Raritebe Wernh.,Sabicea Aubl., andMussaenda L. as well as some paleotropical genera not here considered. The following neotropical genera are excluded from tribe Isertieae:Hippotis Ruiz & Pav.,Pentagonia Benth.,Sommera Schlecht.,Tammsia Karst.,Coccocypselum P. Browne,Schradera Vahl,Didymochlamys Hook, f., andXerococcus Oerst. The position of four genera,Striolaria Ducke,Patima Aubl.,Habroneuron Standl., andNeosabicea Wernh., remains uncertain due to a lack of material.  相似文献   

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Pollen grains of 107 species of 61 genera of the Gardeniinae were investigated by scanning electron and light microscopy. The subtribe is europalynous and grains occur either as monads, tetrads or massulae. Grains are porate, colporate or rarely pororate. The majority of the genera has 3-zonoaperturate pollen grains. However, deviating numbers of apertures occur in Byrsophyllum (4–8) and Pseudomantalania (4–5). Pantoporate pollen occurs in Randia . The average equatorial size (E) of monads varies between 13 μm in Anomanthodiu to 59 μm in Posoqueria . The tetrads vary from 37 μm in Casasia to 61 μm in Calochone and Euclinia . The exine is usually reticulate, but also foveolate, rugulate, perforate and psilate exine occurs in the subtribe. The thickness of the exine is only 0.3 μm in tetrad grains of Randia armata and in the pantoporate monad grains of R. ruiziana , whereas the thickest exine occurs in Posoqueria (2.8 pm) and Euclinia (2.9 μm). Tectal excrescenses are generally absent. However, three genera with pollen in tetrads, namely Euclinia, Gardenia and Oligoco-don , show this feature. Contrary to the subtribe most genera are fairly stenopalynous, but in the neotropical genera Alibertia and Randia several different types of pollen are encountered.  相似文献   

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The nomenclatural and taxonomic history of the genusPerama Aubl. (Rubiaceae) is discussed. The major trends of evolution within the genus are characterized, and the sections of the genus are delimited. A new section,Diperama Kirkb. & Steyerm., is described. The distribution of the genus is updated, and centers of species concentration are indicated. A complete synonymy is given for the genus, and the type species cited. An artificial key to the species is given ; a new combination,P. parviflora (Standl.) Kirkb. & Steyerm., is mads; and three new species are described,P. harleyi Kirkb. & Steyerm.,P. irwiniana Kirkb. & Steyerm., andP. sparsiflora Standl. ex Steyerm. & Kirkb.  相似文献   

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Pollen wall ontogeny of RONDELETIA: odorata was studied with transmission electron microscopy (TEM) and scanning electron microscopy (SEM) from tetrad stage until maturity. The ontogenetic sequence of wall development in RONDELETIA: follows, to some extent, the basic scheme in the angiosperms, i.e., development starts centripetally with the pro-columellae in a plasmalemma surface coating (primexine) at the early tetrad stage when the microspores are still enveloped by callose, until intine formation in young pollen grains. The main ontogenetical features of Rondeletia odorata pollen are (1) the very thin irregular foot layer, (2) development of a continuous layer of radially oriented membranous granular material under the thick endexine, (3) initiation of intine before first mitosis with characteristic radial plasmalemma invaginations, and (4) a strong stretching force upon engorgement just prior to dehiscence, which leads to reduction in thickness of all wall layers. The possible function of Golgi vesicles in the considerable increase in surface area of the plasmalemma at intine initiation is discussed. The endocingulum observed on acetolyzed and sectioned mature grains is explained ultrastructurally.  相似文献   

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Chemical study of the aerial parts of Anthospermum emirnense led to the isolation of one original iridoid glycoside (1) along with six known iridoids (2–7), three lignans (8–10), two flavonoids (11–12), one coumarin (13), two anthraquinones (14–15), two benzoic acids (16–17) and three triterpenoids (18–20). These results are the first chemical data on non-volatile constituents of this genus. The chemotaxonomic significance of these compounds is discussed.  相似文献   

20.
Claes Persson 《Brittonia》2003,55(2):176-201
Agouticarpa, a new genus of the informalAlibertia group (Rubiaceae), is described and illustrated. It comprises six species, and occurs from Costa Rica to Bolivia. Three species are here described as new:Agouticarpa grandistipula, A. hirsuta, andA. velutina. Additionally, three new combinations are made:A. curvifolia andA. williamsii (previously inGenipa) andA. isernii (previously inAlibertia). Agouticarpa is characterized by being dioecious, having elliptic to abovate, membranaceous stipules, male flowers in a branched dichasial or thyrse-like inflorescence, a poorly developed cup-shaped calyx, pollen grains with 3–7 apertures, and large globose fruits.  相似文献   

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