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1.
The tribe Echieae of the subfamily Boragineae (Boraginaceae) is represented in southern Africa by the genera Lobostemon Lehm, and Echiostachys Levyns, endemic to the south‐western Cape region, and two species of Echium L., E. plantagineum L. and E. vulgare L., both introduced weeds of cultivation. Pollen of all these genera was studied and only one pollen type is recognized. Grains are tricolporate, heteropolar and triangular in equatorial view; ora more or less circular and situated towards the broader pole; tectum reticulate with densely spaced lumina; suprateetal nodules are situated at margins of lumina. The P/E ratio varies from 1.08 to 1.63. Genera of the Echieae are sometimes placed in the tribe Lithospermeae. A comparison of the pollen of the studied genera with that of Lithospermum, confirms that the tribe Echieae should be retained. Pollen of Lithospermum is 6–8‐zonocolporate, usually more or less isopolar and with colpi rhombic in outline. The presence of zygomorphic flowers and absence of calciumcarbonate in the fruit wall also support the retention of Lobostemon, Echiostachys and Echium in the Echieae. Pollen grain structure of the southern African Echieae reveals a close relationship between the genera and could support the merging of Lobostemon and Echiostachys with Echium. Lobostemon and Echium can, however, be separated on the position of an annulus. Echium has a minute collar or ring of 5–10 minute, sparingly hairy lobes, very close to the corolla base. Lobostemon and Echiostachys have densely hairy scales, tufts of hair, ridges or protuberances at or near the base of the filaments. Futhermore, the style is 2‐lobed in Echium and simple in Lobostemon.  相似文献   

2.
Onosma maculata Ranjbar & Almasi, a new Boraginaceae species endemic to Iran, is described and illustrated. The new species belongs to Onosma sect. Onosma subsect. Onosma. It is closely related to O. nervosa Riedl, but is easily distinguished by its spotted stem and peduncle (vs no spots), leaves 14–23 cm long (vs leaves 4–12 cm long), pedicel 5–15 mm long (vs pedicel 3–5 mm long), higher density of hairs, and glabrous nutlet (vs villous). Moreover, meiotic chromosome number and behavior were studied in two populations of the new species and it was found to be diploid with 2n = 2x = 16.  相似文献   

3.
We analysed 87 species of Onosma (Boraginaceae) from throughout its distribution range to investigate its evolutionary history. Using nrDNA ITS and two plastid (rpl32‐trnL(UAG) and trnH–psbA) markers, we reconstructed phylogenetic relationships within Onosma by conducting maximum parsimony, maximum likelihood, Bayesian, and BEAST analyses. The analyses revealed that Onosma as currently circumscribed is not monophyletic. However, the vast majority of Onosma species appear to belong to a single clade, the so‐called Onosma s.s. Outside of this core clade is a clade containing O. rostellata, a subclade of Sino‐Indian species and Maharanga emodii. Podonosma orientalis (as O. orientalis) appear only distantly related to Onosma but is more closely related to Alkanna, as also suggested in previous molecular studies. The Onosma s.s. clade includes all representatives of O. sect. Onosma, and encompasses three subsections, i.e. Onosma, Haplotricha and Heterotricha, corresponding to asterotrichous, haplotrichous and heterotrichous groups, respectively, but none of these subsections was retrieved as monophyletic. We observed significant incongruence between nuclear and chloroplast phylogenies regarding the phylogenetic status of the heterotrichous group. A dozen of the Iranian haplotrichous species formed a lineage which may not hybridize with asterotrichous species. Divergence time estimates suggested that the early radiation of Onosma s.l. took place at the Oligocene‐Miocene boundary and the diversification within Onosma s.s. occurred during middle to late Miocene and Pliocene.  相似文献   

4.
Pollen size and exine structure of the following five Onosma L. species from Slovakia and Italy were studied by light and scanning electron microscopy: Onosma echioides, O. tornensis, O. visianii, O. arenaria, and O. pseudoarenaria. Among the taxa studied, O. echioides has the smallest pollen grains in average (10.5–17.5 × 8.0–14.5 μm), and O. pseudoarenaria the largest grains in average (15.3–20.5 × 12.3–16.3 μm). Pollen grains of all 5 species are small sized, 3-syncolporate, subprolate, heteropolar, with ovate equatorial outlines and circular to rounded triangular polar outlines; the tectum is microechinate. A positive correlation is found between pollen size and chromosome number. The value of pollen characters for taxonomic purposes and the position of the taxa studied within the genus Onosma are discussed.  相似文献   

5.
6.
We review the morphological and molecular evidence that Mayden & Chen recently used to infer that the developmentally truncated fish genus Paedocypris is not a member of the teleost order Cypriniformes or carp‐like fishes, but is ‘the basal sister group to all Cypriniformes’. This hypothesis contradicts several previous studies that used molecular sequence data or morphological characters. A review of the morphological characters that Mayden & Chen discussed and mapped onto their ‘simplified tree’ shows that these, analysed alone, rather support a close relationship of the cyprinids Sundadanio, Danionella, and Paedocypris. We also present four additional analyses of morphological data, which all contradict Mayden & Chen's result. Despite its highly reductive skeleton, posing a serious problem when analysing its phylogenetic position with skeletal characters, the presence in Paedocypris of the basioccipital masticatory plate is compelling evidence that it is a member of the Cyprinoidei (Cyprinidae plus Psilorhynchidae). Our reanalysis and exploration of their molecular sequence data shows that only a single gene, EGR3, of the six nuclear genes analysed by Mayden & Chen, is responsible for the position of Paedocypris as ‘the basal sister group to all Cypriniformes’. Three independent methods to visualize and analyse phylogenetic signal and conflict of data sets (phylogenetic networks, splits analysis methods or SAMS, and site‐wise likelihood analyses) reveal a high level of character conflict and noise in Mayden & Chen's data set. The ‘basal’ position of Paedocypris seems to be the outcome of the interplay of two long‐branch effects. We apply the same analytical methods to the data set from Rüber et al.'s molecular analysis of the phylogenetic position of Paedocypris and discuss our findings. We conclude that none of the molecular data sets compiled to date can establish the phylogenetic position of Paedocypris with confidence. Morphological data suggest that Paedocypris and Danionella are sister genera, and that their closest relative is Sundadanio, although the position of these three miniatures among cyprinoids is still unclear. © 2014 The Linnean Society of London  相似文献   

7.
Abstract

The pollen morphology of the Iberian taxa of the genus Xanthium s.l. and of the non-Iberian species X. ambrosioides was studied to help to identify these poisonous, allergenic and invasive taxa and clarify their taxonomic relationships. In addition, the question of the existence and structure of a mesoaperture in the apertural system of Xanthium was also considered. The pollen grains of sections Acanthoxanthium and Xanthium clearly differ by their characters, which supports the separation of both taxa and allows for their distinction based on pollen morphology. It is suggested that the morphological and palynological differences between Xanthium and Acanthoxanthium, together with the lack of hybridisation between the two sections and the monophyly of Acanthoxanthium, could lead to the elevation of the latter to the generic status. The two species of section Xanthium present in the Iberian Peninsula (X. orientale and X. strumarium) and of section Acanthoxanthium are well separated by their palynological features. Likewise, the Iberian subspecies of Xanthium, X. orientale subsp. orientale and X. orientale subsp. italicum are palynologically distinguishable. However, no significant difference could be found between the pollen of X. strumarium subsp. strumarium and of X. strumarium subsp. brasilicum. The pollen data do not support the hypotheses of a hybrid origin for X. strumarium subsp. brasilicum. A mesoaperture intersecting the foot layer and the upper part of the endexine is present in both sections, which is congruent with the results already found for other Asteroideae.  相似文献   

8.
Anew osteostracan genus and species,Victoraspis longicornualis n. gen., n. sp., is described based on material from Rakovets’, present day Ukraine. This new taxon shares characters with the two generaStensiopelta Denison, 1951 andZychaspis Janvier, 1985. A phylogenetic analysis supports the position ofVictoraspis as the sister group to a monophyleticStensiopelta, while the interrelationships of the various species ofZychaspis are poorly resolved. A morphometric analysis is carried out in an attempt to further resolve the taxonomic affinity. This analysis groups all examinedZychaspis species closely together, and further supports the establishment ofVictoraspis as separate genus.   相似文献   

9.
Asterosporium orientale, described on Betula ermanii, is transferred to the genus Prosthemium, and a new combination, P. orientale, is proposed. Because of the morphological similarities, P. asterosporum originally described from twigs of B. pendula is considered as a synonym of P. orientale.  相似文献   

10.
A new species of Boraginaceae, Onosma lhokaensis, is described and illustrated from Xizang, China. The new species closely resembles O. waddellii and O. waltonii in having azure corollas, coherent anthers and glabrous filaments, but differs in having particularly bristly indumentum, observably narrow corolla, longer calyxes and anthers, and remarkable nutlets with stipitate cicatrix. An updated key to the species of Onosma known from Xizang is also provided.  相似文献   

11.
A new Australian genus of Orthotylinae, Myrtlemiris Cheng, Mututantri & Cassis gen.n. , is described, with nine included species described as new to science (M. agnew sp.n. , M. astartephila sp.n. , M. meanarra sp.n. , M. newmanensis sp.n. , M. rubrocuneatus sp.n. , M. russulatus sp.n. , M. silveirae sp.n. , M. tesselatus sp.n. , M. yalgoo sp.n. ). A phylogenetic analysis based on 39 morphological characters is presented for all Myrtlemiris species and 6 outgroup taxa. This analysis establishes Myrtlemiris as monophyletic, defined by a broad apophysis on the left paramere. A key to species is provided and diagnostic characters are illustrated. Myrtlemiris is endemic to southwest Western Australia. Host plants for Myrtlemiris species are near restricted to the myrtaceous tribe Chamelaucieae.  相似文献   

12.
Shikonins are commercially important secondary compounds, known for array of biological activities such as antimicrobial, insecticidal, antitumor, antioxidants, etc. These compounds are usually colored and therefore have application in food, textiles and cosmetics. Shikonin and its derivatives, which are commercially most important of the naphthoquinone pigments, are distributed among members of the family Boraginaceae. These include different species of Lithospermum, Arnebia, Alkanna, Anchusa, Echium and Onosma. The growing demand for plant-based natural products has made this group of compounds one of the enthralling targets for their in vitro production. The aim of this review is to highlight the recent progress in production of shikonins by various biotechnological means. Different methods of increasing the levels of shikonins in plant cells such as selection of cell lines, optimization of culture conditions, elicitation, in situ product removal, genetic transformation and metabolic engineering are discussed. The experience of different researchers working worldwide on this aspect is also considered. Further, to meet market demand, the needs for continuous and reliable production systems, as well as future prospects, are included.  相似文献   

13.
Echium hypertropicum, E. stenosiphon and E. vulcanorum are the three endemics representative of the genus Echium (Boraginaceae) in Cape Verde archipelago. The aim of this study is to provide a first attempt at estimating genetic diversity among natural populations of these endangered Echium species based on RAPD, so as to provide data available for future appropriate strategies for their conservation. PCO and UPGMA of RAPD analysis suggests a close genetic proximity between the Southern endemic species (E. hypertropicum and E. vulcanorum) and shows that the levels of polymorphism strongly differ between these two Echium species (27 and 29% respectively) and E. stenosiphon (74%), the Northern endemic species. Mantel test also corroborates a close genetic proximity between genetic and geographic data. Population genetic analysis of E. stenosiphon revealed low levels of gene flow between islands (Nm = 0.32) being S. Nicolau the most isolated as evident in PCO. Furthermore the differentiation between groups of individuals belonging to putative subspecies was tested by AMOVA. According to our results there is no genetic basis to consider the two subspecies of E. stenosiphon namely ssp. stenosiphon and ssp. lindbergii. Our results enable us to suggest that E. stenosiphon must be ranked as a Threatened species. Measures aiming at conservation of E. hypertropicum and E. vulcanorum must be implemented at short-term taking into account the small number of existing plants and its low genetic variability.  相似文献   

14.
Doronicum caucasicum M. Bieb. (Compositae: Senecioneae) is described and illustrated for the second time in the history of Curtis's Botanical Magazine. Critical examination and reading of the works in which the protologues were published has led to the conclusion that D. caucasicum was published earlier than D. orientale Hoffm., but it is highly likely that the two names were based on the same Adams collection that Adams had annotated as Doronicum orientale. The possibility of Doronicum L. being the sole genus in the recently proposed tribe Doroniceae Panero is discussed. The lack of any present infrageneric classification is commented upon, but this is probably due to insufficient characters in the multivariate analyses used, and where the limits are drawn in molecular analyses. Cultivation and propagation guidelines for the species are provided and currently availability of cultivars is outlined, as are likely pests and diseases.  相似文献   

15.
选择乐安河—鄱阳湖湿地典型植物群落,采用重要值方法评价各样点植物群落特征并筛选出典型优势植物,通过室内理化测试分析不同生境中优势植物植株及其根区土壤中重金属Cu、Pb、Cd的含量;采用生物富集系数(BCF)方法评价不同优势植物对重金属Cu、Pb、Cd的富集特性。结果表明:研究区湿地植物以草本为主,在各样点共发现124种物种,包括蕨类植物2科2属2种,种子植物40科97属122种,并从中筛选出羊蹄、红蓼、鼠曲草、紫云英、苎麻等5种富集能力较强的优势植物;植物根区土壤中的Cu、Cd含量均超过土壤环境质量三级标准,而且Cu、Cd的最高含量分别为824.03、5.03 mg·kg-1;不同优势植物对Cu、Pb、Cd等3种重金属元素中的1种或2种表现出较强的富集能力,其中优势物种红蓼对Cu具有较强的富集能力,含Cu量最高为148.80 mg·kg-1,另一种优势物种鼠曲草对三种元素的生物富集系数均较高,且对Cd的最高富集含量为15.17 mg·kg-1,对Cd的生物富集系数最高值为19.14,高于其他植物10倍以上,鼠曲草对重金属Cd具有富集植物的基本特征,且对Cu和Cd具有共富集特征并具有较高的耐性,紫云英、羊蹄等对Cd的富集能力也较强。上述5种优势植物种群对鄱阳湖湿地Cu、Pb、Cd等重金属污染物的生态修复具有一定参考价值,可作为鄱阳湖湿地重金属污染修复植物的选择对象。  相似文献   

16.
The Palaeotropical goniine genus Dolichocolon Brauer & Bergenstamm is revised and analysed cladistically. Seventeen new species are described from Australia (Queensland, Northern Territory), Cameroon, China, the Democratic Republic of Congo, Ethiopia, Japan, Papua New Guinea, Senegal, Thailand, Uganda, Yemen, and Zimbabwe. The following new synonymy is proposed after direct comparison of primary types: Dolichocolon klapperichi Mesnil, 1967 = Dolichocolon orientale Townsend, 1927 syn. nov. A key to the 21 known species is presented. A cladistic analysis based on 36 morphological characters provides support for the monophyly of Dolichocolon. A sister‐group relationship is indicated between Dolichocolon and Kuwanimyia Townsend, whereas Dolichocolon chiangmaiensis sp. nov. from Thailand takes a position as sister group to all other Dolichocolon species. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 544–584.  相似文献   

17.
Shigeru Kaneko 《Mycoscience》2000,41(2):115-122
The Asian pine gall rust, which has hitherto been assigned toCronartium quercuum distributed in North America, is described asC. orientale, sp. nov. The spermogonial and aecial states occur on hard pines, and the uredinial and telial states occur on various oaks.Cronartium orientale has globose, almost hyaline basidiospores in contrast to the ellipsoid, yellow-orange ones of North AmericanC. quercuum s.l. Characteristics of the new rust species in morphology, DNA analysis, and host alternation are discussed.  相似文献   

18.
A phylogenetic analysis was performed to determine the monophyly of non‐monotypic genera of the terebelliform family Polycirridae, i.e. Polycirrus, Amaeana, Lysilla, and Hauchiella, and the evolution of characters among members of this clade. The monotypic genera, Enoplobranchus and Biremis, were also included, together with members of both known species in Hauchiella. Representative species were included for remaining genera: 14 species of Polycirrus, six species of Amaeana, and six species of Lysilla. Out‐groups consisted of representatives of Spionidae, Cirratulidae, and Sabellariidae, as well as several species of Telothelepodidae. A total of 40 in‐ and out‐group species were coded for 50 subjects (‘characters’) and 117 subject–predicate relationships (‘states’). Although results are consistent with recent phylogenetic studies within Terebelliformia that suggest Polycirridae monophyly, only Hauchiella was found to be monophyletic, albeit part of the more inclusive clade comprising remaining polycirrid genera. Evolutionary transformation series are discussed for selected characters in relation to the non‐monophyly of Polycirrus, Lysilla, and Amaeana. Implications for the use of supraspecific taxa as ‘taxonomic surrogates’ are highlighted. The definition of Polycirridae is emended. © 2015 The Linnean Society of London  相似文献   

19.
Harbach, R. E., Kitching, I. J., Culverwell, C. L., Dubois, J. & Linton, Y.‐M. (2012). Phylogeny of mosquitoes of tribe Culicini (Diptera: Culicidae) based on morphological diversity. —Zoologica Scripta, 41, 499–514. Relationships among taxa of the mosquito tribe Culicini are explored using 169 morphological characters from 86 exemplar species representing the four genera and 26 subgenera of Culicini, most species groups and subgroups of subgenus Culex and an outgroup of five species from five other tribes. We analysed the data set, with multistate characters treated as unordered, under implied weights with values of K ranging from 1 to 20, implemented by TNT. Each analysis, except K = 4, produced a single most parsimonious (fittest) cladogram (MPC). The topology of the ingroup was identical for K = 6–11, whereas the MPCs for K = 14–20 differed only in the position of a single species, which occupied the same position in the K = 16 and K = 6–11 topologies. The K = 9 and K = 16 trees were given further consideration. In both these cladograms, Lutzia is sister to a clade comprising genera Culex, Deinocerites and Galindomyia. The two topologies have 13 clades in common, but their arrangements differ primarily because of Culex (Culex) duttoni acting as a ‘rogue’ taxon. We evaluated the effect of removing this species from the K = 9 and K = 16 analyses and chose the refined K = 9 topology as the best hypothesis of relationships within Culicini. Genus Culex is not monophyletic because it includes Deinocerites and Galindomyia as derived members of the New World subgenera. With the exception of subgenera Culex, Eumelanomyia and Neoculex, there is strong support for the monophyly of all genera and subgenera. Subgenus Culex would be monophyletic were four other subgenera included and three other taxa (the Afrotropical Cx. duttoni, Neotropical Cx. apicinus and the Australasian Atriceps Group) excluded.  相似文献   

20.
The genetic differentiation between the members of the Dugesia (Girardia) dorotocephala group was analyzed by means of multilocus electrophoresis, and comared to that of another planarian secies, D. tahitiensis, also belonging to the subgenus Girardia. The species examined were: D. dorotocephala s.s (2n = 16), D. arizonensis (2n = 8), D. jenkinsae (2n = 8), and the above mentioned D. tahitiensis (2n = 16). The former three species inhabit North America, and show different proportion of fissiparous and sexual individuals; the latter species inhabits Polynesia and is fully asexual. A total of 11 enzyme loci were genetically analyzed: Mdh-1, Mdh-2, Zdh-1, Idh-2, G3pdh, Got-1, Ck, Pgm-2, Ada, Mpi, and Gpi. Low values of observed mean heterozygosity per locus (Ho) were found in the populations studied, ranging from 0 to 0.18 (average 0.08. In asexual populations (except that of D. tahitiensis) fixed heterozygosity was observered in all the individuals for 1 or 2 loci. The genetic divergence between the species examined is very high, with many loci showing discriminating alleles in different taxa (Nei's genetic distance varies from 0.871 to 1.759). The populations of D. dorotocehala s.s., on the contrary, appear to be genetically quite homogenous average D= 0.019), and the genetic distance values are apparently unrelated to their geographic location and to their way of reproduction. The genetic distance between D. tahitiensis, a species not included in the D. dorotocephala group and D. dorotocephala s.s. is 1.314 and hence similar to the D value between two members of;he dorotocephala group: D. dorotocephala and D. jenkinsae (D = 1.303). The genetic relationships among the populations studied were established by UPGMA cluster analysis and multidimensional scaling. The descendence of the North American species with 2n = 8 from a dorotocephala-like ancestor with 2n = 16 is considered. It is suggested that the latter, as well as a tahitiensis-like line, also having 2n = 16, have originated from a common ancestor by geographic isolation.  相似文献   

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