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1.
The two generaPlectranthus andIsodon are compared and found to be very dissimilar.Isodon ist considered to be misplaced inOcimeae subtribePlectranthinae and apparently is more closely related to subtribeHyptidinae. The disjunct genusRabdosiella is compared to these two genera and regarded to be polyphyletic. The AfricanR. calycina (Benth.)Codd is returned toPlectranthus and calledP. calycinus Benth., while the AsianR. ternifolia (D. Don)Codd is placed inIsodon sect.Pyramidium and calledI. ternifolius (D. Don)Kudo.  相似文献   

2.
Fall rates of tumblers ofCombretum and of parachutes ofLeucadendron are shown to be generally high (> 1.8 ms–1). Tumblers contribute up to 77% of the mass of the dispersal unit and parachutes upto 22%. This implies that they are relatively expensive and inefficient in comparison with other propagule types. Morphometric analyses confirm previous findings that species with large seeds also have the largest dispersal structures, but the lowest dispersibility. Finally, there is a correlation between the sizes of these propagules and their associated leaf-size, confirming other studies that link the relative sizes of various plant attributes.  相似文献   

3.
This revision describes, illustrates and documents morphological variation inDoniophyton (Compositae, Barnadesioideae), restricted to Argentina and Chile. Two species are recognized,D. anomalum andD. weddellii (sp. nova), possessing distinct morphological and chromosomal features, elevational tolerances, and nearly allopatric distributions.Doniophyton weddellii occurs primarily in central to northern Andean Chile and Argentina from 1900–4000 m a. s. l.;D. anomalum is found principally in centralwestern Argentina and south into Patagonia at 0–1800 m a. s. l. Close relationship exists withChuquiraga of subfam.Barnadesioideae. It is hypothesized thatDoniophyton evolved out ofChuquiraga in the high central Andes between Chile and Argentina. It is suggested thatD. weddellii differentiated first, correlating with an aneuploid chromosomal decrease from n = 27 (inChuquiraga) to n = 25. Further evolution and chromosomal decrease to n = 24 resulted inD. anomalum, with accompanying migration into southern Andes and Patagonia. Nomenclatural changes result from examination of protologues and type specimens:Doniophyton anomalum replaces the commonly used nameD. patagonicum, and a new species,D. weddellii, is described for the taxon masquerading under the routinely used superfluous nameD. andicola. This paper is dedicated with admiration and respect to emer. Univ.-Prof. DrFriedrich Ehrendorfer, one of the world's outstanding plant systematists, and a leading scientist and administrator of the Institute of Botany of the University of Vienna  相似文献   

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Pairings of monokaryon cultures representingOmphalotus illudens (eastern North America),O. nidiformis (southeastern Australia),O. olearius (southern Europe),O. olivascens (North American Pacific coast), andO. subilludens (southern North America) showed widely variable compatibility patterns.Omphalotus olearius ×O. subilludens ×O. olivascens showed high compatibility, whileO. illudens was significantly less compatible with all other taxa. Isolates ofOmphalotus nidiformis represented an almost genetically isolated biological species. The role of partial compatibility in nomenclatural ranking is discussed.  相似文献   

6.
李腾  唐启明  韦玉梅  赵建成  李敏 《广西植物》2021,41(8):1372-1390
通过对采自广西24个县(市)的1 147份青藓科植物标本的逐一鉴定及相关文献的查阅,确认有广西青藓科植物11属、44种,其中包括广西青藓科植物新记录属1属,即拟异叶藓属(Pseudokindbergia),新记录种7种,分别为匐枝青藓(Brachythecium procumbens)、阔叶尖喙藓(Oxyrrhynchium latifolium)、泛生尖喙藓(O. vagans)、拟异叶藓(Pseudokindbergia dumosa)、华东细喙藓(Rhynchostegiella sinensis)、长肋拟青藓(Sciurohypnum populeum)和弯叶拟青藓(S. reflexum)。该文提供了修订后的广西青藓科植物名录,并对其中的新记录属、种的主要形态学识别特征、生境和地理分布等进行了详细描述。  相似文献   

7.
InMicrocarpaea muscosa gametogenesis, embryo sac development (Polygonum type), endosperm development (cellular), embryogeny (Onagrad type), and seed structure are described. The different modes of endosperm development withinGratioleae are compared.  相似文献   

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Reproduction and/or sperm structure was studied in 18 species belonging to five genera of Galeommatidae from Phuket Island, Andaman Sea, Thailand, and Hong Kong. Incubation of the ova occurs in the inner and outer demibranchs of both gills, and sperm is most probably transferred to the ctenidial brood chamber as masses of agglutinated and non-encapsulated spermatozoa. The smallest specimens are males, but change into the female sex and there is a strong indication that some of the species are alternate hermaphrodites. Dwarf males occur in one species (Galeomma layardi). The sperm of all 18 species studied are of the ent-aquasperm type with a more or less hemispherical acrosome that is tilted with respect to the long axis of the moderately elongated nucleus. It is suggested that this type of sperm affords the best autapomorphy for the family Galeommatidae.  相似文献   

10.
The endemic New Guinean genusIschnea F. Muell. (Asteraceae, Senecioneae, Blennospermatinae) is revised and four species are recognized. Characters of special interest are tubeless ray florets, male disc florets, and secretory spaces in leaves. A principal component analysis is made on theIschnea elachoglossa F. Muell. complex which shows great variation. One new species,I. capellana Swenson, from the Star Mountains, is described. A key, illustrations, and distribution maps to all species are supplied.  相似文献   

11.
James C. Zech 《Brittonia》1999,51(4):415-421
Flavonoid chemistry of the genusMulinum and selected Mulineae taxa was studied. Both flavones and flavonols were identified as C- and O-glycosides. AllMulinum species contain 6,8-di-C-glycosyl chrysoeriol (flavone) and, with the exception of one, quercetin (flavonol). The presence of both flavones and flavonols in this genus weakens previous generalizations that the mulineae contain only flavonols and are primitive compared to other Apiaceae tribes. Based on the selected taxa studied,Azorella appears to differ from bothMulinum andGymnophyton in producing more kinds of flavonols, andGymnophyton appears similar toMulinum in the production of both chrysoeriol and quercetin as well as relatively few compounds. The flavonoid profile ofAsteriscium glaucum is reported as well. In general, a more homogeneous flavonoid compound composition for the Apiaceae is suggested.  相似文献   

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Eight species in Pleomassariaceae are described and illustrated. They are Pleomassaria maxima, Pl. swidae, Pl. siparia “type A,” Prosthemium canba, Asteromassaria macroconidica, A. pulchra, Splanchnonema mori, and S. argus. Of these, Pl. swidae on twigs of Swida controversa, Pr. canba on Betula ermanii, and A. macroconidica on twigs of Prunus ×yedoensis and an unknown woody plant are new. Three species, Pl. siparia “type A,” A. pulchra, and S. argus, are reported from Japan for the first time. A new combination, S. mori (≡ Massaria mori), is proposed.  相似文献   

14.
The various classifications of the orchid tribeNeottieae are reviewed and a new classification is proposed that divides the tribe into three subtribes,Neottiinae, Limodorinae, andCephalantherinae, based primarily on characters of the column (gynostemium). A cladistic analysis illustrates that these three subtribes are more closely related to one another than either is to any other group in subfam.Neottioideae, although there are very few apomorphic characters for the tribe. Pollination biology is also discussed showing links between breeding systems and distribution. There is also a possible role between column and labellum morphology and the emergence of a deceptive pollination syndrome from one of reward.  相似文献   

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Morphological and seed protein studies of selected species ofFestuca were performed to elucidate the relationships between species of sect.Ovinae and their affinity with other fescues.Festuca rubra andF. heterophylla (extravaginale group) had higher phenetic affinity with taxa of sect.Scariosae, Montanae andBovinae than with members of their own section. 5 species of the intravaginale group (F. ovina, F. capillata, F. valesiaca, F. sulcata, F. trachyphylla) were fairly uniform and well defined by protein and morphological data. This supports current systematic thinking and does not agree withHackel's (1882) classification of this group.  相似文献   

17.
The occurrence of eight biflavones belonging to the biluteolin series, the apigenin-luteolin series and the 2,3-dihydro-biluteolin series, and one monomeric flavone with an acid group, was investigated in six taxa ofBartramia with emphasis on sect.Ithyphyllae. The variation of biflavone profiles contributes to the characterization of theBartramia species studied; substitution patterns signalize relevance also on the sectional level. Based upon the flavonoid composition,Bartramia afro-ithyphylla is suggested to be transferred from sect.Ithyphyllae to sect.Bartramia of the genusBartramia.  相似文献   

18.
Laboulbenia stenolophi is reported for the first time from Japan.Stenolophus iridicolor andS. propinquus are added as new hosts. The crowded antheridia and the protruding (bulging) cell IV are characteristic of this fungus, although thalli with an almost normal cell IV sometimes occur.Laboulbenia anoplogenii onAnoplogenius is easily distinguished from what has been calledL. anoplogenii onStenolophus, Astigis, Abacetus andChlaeminus by the following characters: 1) no crowded antheridia can be observed throughout thallus development, but many sterile long branches can be observed instead; 2) cell IV starts to undergo cell division early in thallus development; 3) cell V extends downward to the level of cell VII, rather than extending only as far as the perithecial basal cells; and 4) cell VI is usually longer and extends farther distally than cell III.Anoplogenius is the host genus ofL. anoplogenii and the records from other hosts represent misapplied names.  相似文献   

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20.
A cladistic analysis of 44 species of the generaCladina andCladonia is presented.Pycnothelia papillaria, Cladia aggregata andC. retipora were used as outgroup taxa. The consensus of all equally parsimonious trees suggests a common ancestral origin for species inCladonia andCladina while the generaPycnothelia andCladia cluster outside this group. The results do not support distinction ofCladina at genus level although it is distinguished as a monophyletic group but within the genusCladonia. The current sectional division ofCladonia is not supported. SectionsCocciferae andHelopodium are best supported but even these groups as currently delimited seem to in include elements that are more closely related to species of the other sections, e.g.C. carneola of sect.Cocciferae andC. pityrophylla of sect.Helopodium. Sections such asUnciales andPerviae seem to be artificial assemblages. In general the evolutionary scheme of the genus seems to be more complicated than revealed by the current sectional division.  相似文献   

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