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1.
Cremanthodium weixiense (Asteraceae, Senecioneae), a new species from northwestern Yunnan, China, is described and illustrated. The new species is referred to C. ser. Calcicola based on its palmately veined leaves, discoid capitula and leaflike, herbaceous phyllaries. However, it is unique in this series in having dissected leaves. It is somewhat similar to C. pinnatisectum in C. ser. Campanulata in the dissected leaves and the discoid capitula, but differs by the suborbicular (versus subreniform) basal leaves with deeply cordate (versus subtruncate) bases and very narrow (versus obviously divergent) sinuses, the presence (versus absence) of a conspicuously sheathed petiolar base of stem leaves, the broadly cylindrical (versus campanulate) involucres and the leaflike, herbaceous (versus petaloid, membranous) phyllaries.  相似文献   

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The species of the New World syrphid genus, Quichuana Knab, 1913 (Diptera: Syrphidae: Eristalini), are revised and the genus is re‐diagnosed. Twenty‐four new species are described, bringing the total number considered valid to 48. New species were mostly reared from Bolivia, Brazil, Costa Rica, El Salvador, Mexico, Peru, Trinidad, and Venezuela. The male of Quichuana picadoi is described for the first time. Quichuana championi is proposed as a synonym of Quichuana cincta, Quichuana aurata as a synonym of Quichuana angustiventris, and Quichuana sepiapennis as a synonym of Quichuana calathea. Quichuana inca var. brevicera is raised to specific status. Lectotypes are designated for Helophilus auratus, Quichuana bezzii, Quichuana fasciata, and Quichuana parisii. A species‐level identification key for both males and females is provided. Male genitalia of 18 species are illustrated. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 72–131.  相似文献   

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New material from the Atlantic sector of the Antarctic Ocean allows a revision of the Antarctic genus Notaeolidia Eliot, 1905. One new species (Notaeolidia schmekelae sp.n.) is described. N. depressa Eliot, 1905 and N. gigas Eliot, 1905, which arc poorly known, arc redescribed. N. rufopicta Thiele, 1912, N. robsoni Odhner, 1934, N. subgigas Odhner, 1944, N. alutacea Minichev, 1972 and N. flava Minichev, 1972 are synonymized with N. depressa. N. purpurea Eliot, 1905 is synonymized with N. gigas. The monogeneric family Notaeolidiidae Odhner, 1926. is characterized by the following autapomorphy: "nephroproct in front of the genital apertures". Too little is known to elaborate the phylogenetic position of the family Notaeolidiidae within the cladobranch Nudibranchia.  相似文献   

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Gynoxys dilloniana from northern Peru is described and illustrated, and its taxonomic relationships discussed.  相似文献   

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Clibadium L. (Asteraceae, Heliantheae) is a genus of 29 species distributed throughout latin America, from Mexico to Peru, and in the West Indies, with high numbers of species in Costa Rica, Colombia, and Ecuador.Clibadium includes shrubs and small trees; usually with loosely aggregated capitula; herbaceous phyllaries arranged in 1–5 series; receptacles usually paleaceous throughout; corollas of pistillate florets 2–4-lobed; corollas of the staminate florets 4–5-lobed; purple to black anthers; and chromosome numbers alln=16. Two sections of species previously recognized are here considered as subgenera (subg.Paleata and subg.Clibadium) containing two and four sections, respectively.Clibadium subg.Paleata contains five species distributed in sects.Eggersia (3 spp.) andTrixidium (2 spp.), and subg.Clibadium has 24 species distributed among sects.Clibadium (6 spp.),Glomerata (9 spp.),Grandifolia (5 spp.), andOswalda (4 spp.).  相似文献   

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Twenty-two populations of seven species of Cremanthodium from high altitude regions of western China were observed karyologically. C. ellisii, C. microglossum, C. brunneo-pilosum, C. stenoglossum, C. discoideum and C. lineare all had the same chromosome number of 2 n = 58 whereas C. humile had 2 n = 60. All chromosome numbers of these species are documented here for the first time. The basic number of x = 30 is new for this genus. The karyotypes of all species belong to 2A type according to Stebbins' asymmetry classification of karyotypes. Two basic chromosome numbers, x = 30 and x = 29 in Cremanthodium , correspond exactly to two branching patterns in this genus, sympodial versus monopodial. The systematic and taxonomic statuses of the sympodial species need further study. The karyomorphological data provide no support to the sectional subdivision in Cremanthodium .  相似文献   

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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   

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The unusual disjunct distribution of the yellow-flowered, radiate, Northern Cape endemic Emilia hantamensis J.C.Manning & Goldblatt, relative to the other Emilia species in southern Africa, prompted investigation into its phylogenetic position and relationships. Phylogenies based on the ITS and trnL–trnF regions reveal that it is not a member of the genus Emilia but belongs in a well-supported clade with Bolandia, a genus comprising five species mainly from the Western and Northern Cape, and the monotypic genera Stilpnogyne and Mesogramma. It is placed sister to Bolandia and its cypselas match those of Bolandia in shape, colour and indumentum, except for a distinct ridge of hairs on the inner rib of the ray cypselas. It is further distinguished from Bolandia by its annual habit and conical disc floret style apices and obtuse to rounded ray floret style apices. It is recognised and described here as a new monotypic genus, Bertilia Cron with the single species B. hantamensis (J.C.Manning & Goldblatt) Cron.  相似文献   

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The new genusCaucasalia is described. Four species are included, previously referred toSenecio, Cacalia, Cineraria, Pojarkovia orAdenostyles. The latter genus may be the closest relative, being similar in habit and chromosome number, but different in floret colour and style morphology. The new genus is centered in the Caucasus mountains, with extensions into Anatolia.Dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer on the occasion of his 70th birthday  相似文献   

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Abstract

The family Acanthoclinidae includes 10 species: Acanthoclinus fuscus Jenyns, 1842; Taumakoides littoreus ((Forster) Bloch & Schneider, 1801); T. rua n. sp.; T. marilynae n. sp.; T. matti n. sp.; Belonepterygion fasciolatum (Ogilby, 1889); Beliops xanthokrossos n. gen. et sp.; Acanthoplesiops indicus (Day, 1888); A. hiatti Schultz, 1953; and A. psilogaster n. sp. Acanthoclinus quadridactylus (Bloch & Schneider, 1801) and A. trilineatus Griffin, 1933, are reduced to synonymy under Taumakoides littoreus ((Forster) Bloch & Schneider, 1801).

Osteological and morpological character states, between and within genera, suggest that Acanthoclinus and Taumakoides are close to the stock from which the family is derived. There is also compelling evidence that T. matti is the least specialised species of Taumakoides. Progressive specialisation is evident in the remaining genera, with Acanthoplesiops being the most highly specialised.

The family occurs primarily in shallow waters of the Indian and western Pacific oceans; most of the species are found about New Zealand. The centre of origin of the Acanthoclinidae was probably on the Indian-Australian Plate (which includes the New Zealand continental shelf). Acanthoplesiops hiatti and A. indicus are considered to be endemics of the Pacific and African plates, respectively.

A key to species is included.  相似文献   

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The key process in speciation concerns the formation and maintenance of reproductive isolating barriers between diverging lineages. Although species boundaries are frequently investigated between two species across many taxa, reproductive isolating barriers among multiple species (>2) that would represent the most common phenomenon in nature, remain to be clarified. Here, we use double digest restriction‐site associated DNA (ddRAD) sequencing to examine patterns of hybridization at a sympatric site where three Ligularia species grow together and verify whether those patterns contribute to the maintenance of boundaries among species. The results based on the RAD SNP datasets indicated hybridization Ligularia cyathiceps × L. duciformis and L. duciformis × L. yunnanensis were both restricted to F1s plus a few first‐generation backcrosses and no gene introgression were identified, giving rise to strong reproductive isolation among hybridizing species. Moreover, hybrid swarm simulation, using HYBRIDLAB, indicated the RAD SNP datasets had sufficient discriminatory power for accurate hybrid detection. We conclude that parental species show strong reproductive isolation and they still maintain species boundaries, which may be the key mechanism to maintain species diversity of Ligularia in the eastern Qinghai‐Tibetan Plateau and adjacent areas. Moreover, this study highlights the effectiveness of RAD sequencing in hybridization studies.  相似文献   

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Phagnalon rechingeri spec. nova from S Baluchestan (Iran) is described as a species new to science and illustrated; its relationships to other species of the genus, in particular to thePh. woodii group from S Arabia, are discussed.Dedicated to Hofrat Univ.-Prof. DrK. H. Rechinger on the occasion of his 80th birthday.  相似文献   

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Taxonomic revision of South American species of Grindelia Willd. has revealed a new species from Argentina, with homogamous capitula and cushion-shaped habit. The taxon is here described and illustrated.  相似文献   

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湖南菊科紫菀属—新种—吉首紫菀   总被引:1,自引:0,他引:1       下载免费PDF全文
吉首紫菀 新种 图 1AsterjishouensisW .P .LietS .X .Liu ,sp .nov .Fig.1SpeciesA .baccharoidi(Benth .)Steetz.affinis,sedcaulesimplici,caulorumfoliorumlami nislineari lanceolatisusqueoblongo lanceolatisapicelongeacuminatis,nervislateralibusincon spicuis,capitulis 1~ 4inracemumdi…  相似文献   

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