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1.
23种伞形科植物果实形态及其分类学意义   总被引:2,自引:0,他引:2  
张乐  李敏  赵建成 《西北植物学报》2015,35(12):2428-2438
该实验采用徒手切片法对伞形科17属23种植物的果实进行了外部形态和解剖特征的观察,结果表明:伞形科果实有背腹压扁、两侧压扁和不压扁3种类型;侧棱有宽、有窄;油管的分布有棱槽单油管型和棱槽多油管型;花柱基多数为圆锥状,少数种的花柱基为扁平垫状;萼齿明显或不明显。通过进一步对属间和属内果实解剖特征的比较得出:(1)果实表面被钩刺或刚毛及果棱特征在属间差异明显,在属内表现出一致性,可作为伞形科属间分类的依据。(2)果实横切面的形状、胚乳腹面的凹凸以及萼齿的形态特征在属内种间的分类研究中有重要的意义。基于果实形态特征,编制了17属23种植物的分种检索表。  相似文献   

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A review of available Caribbean Island red-lists species (CR and EN categories based on the IUCN guidelines from 2001, and E category established according to the IUCN guidelines from 1980) is presented. A database of over 1,300 endemic species that are either Critically Endangered or Endangered sensu IUCN was created. There are molecular systematic studies available for 112 of them. Six of these species (in six genera) are the only members of early divergent lineages that are sister to groups composed of a large number of clades. Seven of the species (in seven genera) belong to clades that have a small number of taxa but are sister to species/genus-rich clades. Ten of the species (in six genera) are sister to taxa restricted to South America or nested in clades endemic to this region. Fifty-seven of the species (in 35 genera) are sister to Caribbean Island endemic species. Erigeron belliastroides, an Endangered (EN) Cuban endemic, is sister to the Galapagos genus Darwiniothamnus. The phylogenetic placement of four of the threatened species resulted in changes in their taxonomic placement; they belong to polyphyletic or paraphyletic genera.  相似文献   

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The phylogenetic position of the African and Malagasy species of Pimpinella is assessed using nrDNA ITS sequence data and a representative sampling of the genus, including 16 species from Africa and Madagascar and 26 species from Eurasia. The results of maximum parsimony and Bayesian analyses of these data show that the African and Malagasy species ally with their Eurasian counterparts in Pimpinelleae. The genus Pimpinella is rendered paraphyletic by the inclusion of African Cryptotaenia and the small African and Malagasy endemic genera Frommia and Phellolophium. Within a paraphyletic Pimpinella, three major clades are recovered, with the African species occupying two of these clades. The current sectional classification of the genus, based predominantly on fruit vestiture, is largely artificial. Chromosome base number, however, was found to be consistent with the groupings recovered in the molecular analyses. Those African and Malagasy Pimpinella species with a chromosome base number of x = 11 and largely glabrous petals and fruits, form the earliest diverging clade together with Frommia, which also has a base count of n = 11 and glabrous petals and fruits. The remaining African species ally with several Eurasian species of Pimpinella and share a chromosome base number of x = 9 and usually hairy petals and fruits.  相似文献   

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《Journal of Asia》2022,25(2):101903
Ceylonitermellus Emerson is a rarely collected soil inhabiting nasute termite endemic to Oriental region with three known species. A fourth species, Ceylonitermellus sahyadriensis sp. nov. is described and illustrated based on morphological characters of soldier and gut morphology of workers. Both the castes have poorly sclerotized body and paler in colour. This is the second species from India and fourth species of the genus from world. The species can be distinguished from the closely related C. periyarensis by the pyriform and shorter head capsule and with other two species of the genus by its larger head capsule as compared to C. kotuae and smaller head capsule as compared to C. hantanae. The new species was collected from tropical evergreen forest from a small colony near the base of a tree.LSID: urn:lsid:zoobank.org:pub:34616357-2CC9-46B2-8B8D-3CFD984CED89.  相似文献   

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Middle Permian Inoceramus-like bivalves of the genera Kolymia Licharew and Cyrtokolymia Astafieva endemic to the East Boreal Biogeographic Realm are considered. Cyrtokolymia, previously regarded by the author as endemics of the Verkhoyansk–Okhotsk Province and including only the type species, are also recorded in the Kolyma–Omolon Province, where they are represented by the endemic species C. bobini sp. nov. An emended diagnosis of the genus Cyrtokolymia is provided. The genus Kolymia comprises about 30 species. The greatest diversity of Kolymia (24 species, 13 of which are endemic) is known from the Verkhoyansk–Okhotsk Province, which is the center of diversification of this genus. The Kolyma–Omolon Province is characterized by 12 species, only three of which are endemic. In other provinces of the East Boreal Realm, only individual members of Kolymia are known. From the Middle Permian of the Omolon Massif, northern Verkhoyansk Region, and Penzhinsky Ridge, the following new species are described: Kolymia posneri Muromzeva, Kusnezov et Biakov, sp. nov., K. pontoneica Biakov, sp. nov., K. simkiniformis Biakov, sp. nov., and Cyrtokolymia bobini Biakov, sp. nov.  相似文献   

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瑞香属和荛花属为瑞香科瑞香亚科的落叶或常绿灌木,中国西南部是瑞香属和荛花属的重要分化中心。全世界共有瑞香属95种、荛花属70种,中国分布有瑞香属52种、荛花属49种。瑞香属和荛花属的分类学研究一直存在不同程度的分歧。花盘形状和果实类型在传统分类中一直是区分瑞香属和荛花属的典型特征,而花盘形态和果实类型在2个属中存在交叉和过渡,部分植物分类学家根据这些特征将两个属进行过不同程度的归并。该研究采用数量分类法对瑞香属77种(变种)和荛花属62种(变种)植物,选取32个形态学性状进行聚类分析和主成分分析。结果表明:聚类分析和主成分分析均显示两属均未形成单系类群。在主成分分析中,前3个主成分分析的贡献值为35.56%,传统分类中用来区分两属的花盘形状、叶序及果实类型等特征对前3个主成分贡献相对较小,因此,传统分类学中对这两个属进行区分的性状并没有典型的分类学意义。同时,聚类图和主成分分析得到的散点图均不能将这两个属区分开来。数量分类研究结果显示两属植物存在明显的交叉,支持瑞香属和荛花属不是两个独立自然类群的观点。  相似文献   

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A new genus and species Kurtamia bykhovskyi gen. sp. nov., similar to the genus Archamia, but differing by presence of a foliiform-widened pleural ribs at the 5–9 vertebrae and combinations of certain other characters are described. Kurtamia and Archamia are considered as sister groups. The structures of pleural ribs and pterygophores of the anal-fin spiny rays in the new species have several similarities with those in the family Kurtidae, which should be considered close to Apogonidae. The relationships between Kurtamia, Apogonidae, and Kurtidae are considered.  相似文献   

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Our main goals were to identify diagnostic characters at the species, genus, and subfamily levels, find anatomical features with potential for future morphological and molecular (combined) phylogenetic analyses, and to reconstruct the evolution of wood anatomical characters in two subfamilies of Primulaceae in a molecular phylogenetic framework. We investigated twenty-seven species from the woody Myrsinoideae (4 genera) and Theophrastoideae (2 genera) using scanning electron, light, and epifluorescence microscopy. Samples were prepared using standard protocols. Based on the wood anatomical characters, we were able to identify synapomorphies and to detect evolutionary trends of interest for the genera and subfamilies. Both subfamilies share the presence of diffuse porosity, simple perforation plates, septate fibres, and scanty paratracheal axial parenchyma. Theophrastoideae species have rays?>?10 cells wide and short (<?350 µm) vessel elements, and Myrsinoideae have breakdown areas in rays and longer vessel elements. Ardisia and Stylogyne have scalariform intervessel pits, Myrsine exhibit breakdown areas in rays, and two Cybianthus species from subgenus Weilgetia have distinguishing features (e.g., scalariform perforation plate in C. nemoralis and the absence of rays in C. densiflorus). Overall, when combining characters, we were able to segregate the Neotropical Primulaceae subfamilies and genera from each other and from the subfamily Maesoideae based on wood anatomy.  相似文献   

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《Geobios》2014,47(5):335-343
Taxonomic studies on chironomids of the tribe Tanytarsini recorded in Eocene Baltic amber from the Rovno region have revealed two new species: Archistempellina perkovskyi and Stempellinella ivanovae. Both species display interesting characters supporting evolutionary trends in the tribe. A. perkovskyi nov. sp. combines plesiomorphic characters, thus consolidating the hypothesis that the genus Archistempellina is one of the basal lineages of the tribe Tanytarsini. The antennal flagellum composed of 13 discernible segments found in S. ivanovae nov. sp. is defined as a plesiomorphic character state opposite to a reduced number of flagellomeres in extant species; the nipple-like process on the apex of the gonostylus is recognised as a unique character in the Tanytarsini and a possible homologue of the horn-like tip of the gonostylus known from several extant species of the genus Stempellinella Brundin. A key to determination of all genera and species of the Tanytarsini recorded in the Eocene is presented. Notes on evolutionary trends in the tribe are also provided.  相似文献   

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Vegetative, floral and fruit anatomy and morphology ofUldinia, a monotypic hydrocotyloid genus endemic to Australia, are described in detail. These observations, when compared to available reports for other genera of Hydrocotyloideae, indicate thatUldinia is most closely allied to members of Hydrocotyleae—Hydrocotylinae, and, in particular, toTrachymene. Similarities between these two genera include such anatomical and morphological characteristics as habit and leaf morphology, stem anatomy, trichome anatomy, inflorescence morphology, floral morphology, and several details of the floral venation pattern and fruit anatomy. Nevertheless, the nature and development of the fruit wings, the papillae and retrorse barbs of the fruit, the absence of a carpophore, the differences in floral venation at the commissure and in the upper portion of the mericarp, and the orientation of fibers in the endocarp, all provide a basis for the generic distinctness ofUldinia. These comparative studies also point to the need for a possible re-evaluation of relationships within the subtribes of Hydrocotyleae.  相似文献   

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Molecular phylogenetic analyses of 18S rDNA (SSU) gene sequences confirm the placement of Crusticorallina gen. nov. in Corallinoideae, the first nongeniculate genus in an otherwise geniculate subfamily. Crusticorallina is distinguished from all other coralline genera by the following suite of morpho‐anatomical characters: (i) sunken, uniporate gametangial and bi/tetrasporangial conceptacles, (ii) cells linked by cell fusions, not secondary pit connections, (iii) an epithallus of 1 or 2 cell layers, (iv) a hypothallus that occupies 50% or more of the total thallus thickness, (v) elongate meristematic cells, and (vi) trichocytes absent. Four species are recognized based on rbcL, psbA and COI‐5P sequences, C. painei sp. nov., the generitype, C. adhaerens sp. nov., C. nootkana sp. nov. and C. muricata comb. nov., previously known as Pseudolithophyllum muricatum. Type material of Lithophyllum muricatum, basionym of C. muricata, in TRH comprises at least two taxa, and therefore we accept the previously designated lectotype specimen in UC that we sequenced to confirm its identity. Crusticorallina species are very difficult to distinguish using morpho‐anatomical and/or habitat characters, although at specific sites, some species may be distinguished by a combination of morpho‐anatomy, habitat and biogeography. The Northeast Pacific now boasts six coralline endemic genera, far more than any other region of the world.  相似文献   

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A comparative morphological analysis of all known members of the Lower-Middle Cambrian genus Kutorgina, one of the brachiopod genera with a carbonate shell that are oldest and richest in species. The evolution of the genus is discussed, and the borders between the Kutorgina species are emended. A new species, Kutorgina elanica sp. nov., is described.  相似文献   

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The history of the study and review of generic and species diversity of Mesozoic rissoid gastropods are provided. The generic composition of Jurassic rissoid gastropods is revised, so that it is proposed to regard them as the family Rissoidae, comprising the genera Bralitzia, Buvignieria, Palaeoceratia, and Palaeorissoina. It is tentatively proposed to assign the genus Hudlestoniella to Rissoidae; this is caused by insufficient morphological knowledge of this genus. The family Palaeorissoidae is regarded as a synonym of Rissoidae. Stratigraphical and geographical distribution of Rissoidae genera is reviewed. From the Jurassic of European Russia, the following species of the genus Buvignieria are described: B. calloviana Gründel, B. imminuera Gründel, B. paucicostata Gründel, B. eichwaldiana (Rouillier), B. choroshovensis Gerasimov, and B. gruendeli sp. nov. The morphological characteristics and stratigraphical distribution of these species are provided. Based on extensive material, the taxonomic significance of particular conchological characters for the establishment of species is discussed.  相似文献   

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The tribe Psoraleeae (Leguminosae subfamily Papilionoideae) comprises 185 species in nine genera that have a nearly worldwide distribution, occurring predominantly in Mediterranean regions. About 60% of the species belong to the genera, Otholobium C.H.Stirt. and Psoralea L., which have a centre of diversity in the Cape Floristic Region of South Africa. Since previous molecular studies have sampled only a few species of the tribe from this region, this study sought to determine the phylogenetic position of the southern African genera and to test whether they are monophyletic. Phylogenetic relationships were reconstructed using DNA sequence data (trnL-F, rpoB-trnC and ITS) and seven morphological characters, which diagnose the two southern African genera. The data were analysed using the parsimony method. There was strong support for the Psoraleeae as a clade, but most of the nodes within the large genera were poorly supported. The southern African species of Psoralea and Otholobium together formed a strongly supported clade. This clade was sister to the genus Hoita Rydb., but without support. However, the Psoralea species were nested within the southern African Otholobium. Additionally, some South American species that are currently recognised as Otholobium were resolved in a clade distinct from the southern African species, making Otholobium polyphyletic. Morphological characters that separate Otholobium and Psoralea are discussed. Finally, the southern African genera as currently circumscribed are not monophyletic. However, further investigations using more informative DNA loci are required to validate this observation. Furthermore, the taxonomic placement of the South American species needs to be reviewed.  相似文献   

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New species of the genera Gymnothorax (fam. Muraenidae) and Parapercis (fam. Mugiloididae) are described from coastal waters of central Vietnam. G. emmae sp. n. is a common species all along the coast from the Van Phong Bay to the Phan Thiet Bay and differs from other species of this genus in characters of coloration, dentition, and the vertebral formula. P. bicoloripes sp. n. is common in the Phan Thiet Bay and is also know from one specimen from the Nha Trang Bay; from other species of the genus, it differs in coloration and meristic characters.  相似文献   

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