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1.
The African genus Welwitschiella has traditionally been placed in tribe Heliantheae. Our phylogenetic analysis of chloroplast DNA ndhF sequence data, however, reveals that it is part of tribe Astereae. In order to assess the relationships of this genus within the tribe, we produced a phylogeny based on ITS (nrDNA) sequence data of a sample including Amellus, African Conyza, Chrysocoma, Felicia spp., Mairia, Poeciliopsis, Printzia, Welwitschiella and Zyrphelis. Both parsimony and Bayesian analyses were done. The Bayesian analysis showed that African genera form a basal grade in tribe Astereae along with the Chinese Nannoglottis and South American and New Zealand genera, with Printzia being the earliest diverging member of the tribe. Mairia occupies an isolated position. Amellus, Chrysocoma, Felicia, Poecilolepis and Zyrphelis belong to subtribe Homochrominae, a South African radiation that also includes the St Helena endemics Commidendron and Melanodendron. Pteronia appears isolated, though it might be close to the Homochrominae. Welwitschiella is placed in the latest diverging African clade, subtribe Grangeinae, which also includes Grangea, Psiadia, Nidorella, and the African Conyza species except C. gouani. This subtribe is sister to the Eurasiatic subtribe Bellidinae, and together they are sister to the Astereae crown lineages of Australasia-Asia and South and North America.  相似文献   

2.
《Phytochemistry》1987,26(4):1049-1052
The investigation of several South African representatives of the tribe Senecioneae afforded in addition to known compounds a caryophyllene and a bicyclogermacrene derivative, two furoeremophilanes, three bisabolone derivatives and a guaiane derivative.  相似文献   

3.
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   

4.
The Gnaphalieae are a group of sunflowers that have their greatest diversity in South America, Southern Africa, and Australia. The objective of this study was to reconstruct a phylogeny of the South African Gnaphalieae using sequence data from two noncoding chloroplast DNA sequences, the trnL intron and trnL/trnF intergenic spacer. Included in this investigation are the genera of the Gnaphalieae from the African basal groups, members of the subtribes Cassiniinae, Gnaphaliinae, and Relhaniinae, and African representatives from the large Old World genus Helichrysum. Results indicate that two Gnaphaloid genera, Printzia and Callilepis, should be excluded from the Gnaphalieae. In most trees the Relhaniinae s.s. (sensu stricto) and some of the basal taxa comprise a clade that is sister to the remainder of the tribe Gnaphalieae. The Relhaniinae, which are restricted to Africa, are not a monophyletic group as presently circumscribed, nor are the South African members of Helichrysum, the Cassiniinae and Gnaphaliinae. There is general agreement between our molecular analysis and that of morphology, particularly in the terminal branches of the trees.  相似文献   

5.
Anthemideae (Asteraceae) is primarily a north temperate, Old World tribe of 109 genera and approximately 1740 species. We sequenced a 1200-bp portion of chloroplast gene ndhF for representative genera and subtribes and constructed a phylogeny for the tribe. There is support for monophyly of subtribes Chrysantheminae and Gonosperminae and for portions of some subtribes. However, our molecular phylogeny differs significantly from traditional classifications and from previously published morphological phylogenies of the tribe. Many South African genera from several different subtribes form a basal grade, indicating multiple, relictual lineages. Eurasian genera form a recently derived clade that includes the Mediterranean genera of the Iberian Peninsula and North Africa. There is little resolution or support for the placement of eastern Asian genera. Apparently, the tribe originated in the Southern Hemisphere, presumably in Africa, with the Eurasian and Mediterranean members being derived from a common ancestor.  相似文献   

6.
The Platypleurini is a large group of charismatic cicadas distributed from Cape Agulhas in South Africa, through tropical Africa, Madagascar, India and eastern Asia to Japan, with generic diversity concentrated in equatorial and southern Africa. This distribution suggests the possibility of a Gondwanan origin and dispersal to eastern Asia from Africa or India. We used a four‐gene (three mitochondrial) molecular dataset, fossil calibrations and molecular clock information to explore the phylogenetic relationships of the platypleurine cicadas and the timing and geography of their diversification. The earliest splits in the tribe were found to separate forest genera in Madagascar and equatorial Africa from the main radiation, and all of the Asian/Indian species sampled formed a younger clade nested well within the African taxa. The tribe appears to have diversified during the Cenozoic, beginning c. 50–32 Ma, with most extant African lineages originating in the Miocene or later, well after the breakup of the Gondwanan landmass. Biogeographical analysis suggests an African origin for the tribe and a single dispersal event founding the Asian platypleurines, although additional taxon sampling and genetic data will be needed to confirm this pattern because key nodes in the tree are still weakly supported. Two Platypleurini genera from Madagascar (Pycna Amyot & Audinet‐Serville, Yanga Distant) are found to have originated by late Miocene dispersal of a single lineage from Africa. The genus Platypleura is recovered as polyphyletic, with Platypleura signifera Walker from South Africa and many Asian/Indian species apparently requiring assignment to different genera, and a new Platypleura concept is proposed with the synonymization of Azanicada Villet syn.n. The genera Orapa Distant and Hamza Distant, currently listed within separate tribes but suspected of platypleurine affinity, are nested deeply within the Platypleurini radiation. The tribe Orapini syn.n . is here synonymized while the tribe Hamzini is pending a decision of the ICZN to preserve nomenclatorial stability.  相似文献   

7.
Abstract. The South African genus Pameridea and its two species are redescribed. The tribe Pamerideini, founded for this genus only, is removed from synonymy with Mirini (subfamily Mirinae) and transferred to Dicyphini (subfamily Bryocorinae), falling as a synonym of the subtribe Dicyphina. The bugs live only on intensely viscid small shrubs of the genus Roridula. This plant genus is the only member of its family but the bug genus is closely related to two widespread tropical dicyphine genera.  相似文献   

8.
The aerial parts of the South African composite Printzia laxa contain two manoyl oxides and three clerodane derivatives together with two further acids, which belong to a new type of diterpene, biogenetically closely related to the clerodanes. The structures have been elucidated by spectroscopic methods. The constituents may indicate some relationship of Printzia to the tribe Astereae.  相似文献   

9.
The Yoruba are an important ethnic group mainly occupying Southwestern Nigeria. Mainly for genetic reasons, this very large tribe happens to present the highest dizygotic twinning rate in the world (4.4 % of all maternities). The high perinatal mortality rate associated with such pregnancies has contributed to the integration of a special twin belief system within the African traditional religion of this tribe. The latter is based on the concept of a supreme deity called Olodumare or Olorun, assisted by a series of secondary gods (Orisha) while Yoruba religion also involves immortality and reincarnation of the soul based on the animistic cult of ancestors. Twins are therefore given special names and believed to detain special preternatural powers. In keeping with their refined artistic tradition, the Yoruba have produced numerous wooden statuettes called Ibejis that represent the souls of deceased newborn twins and are involved in elaborate rituals. Among Yoruba traditional beliefs and lore some twin-related themes are represented which are also found in other parts of the world. Basic features of the original Yoruba beliefs have found their way into the religious traditions of descendants of African slaves imported in the West Indies and in South America.  相似文献   

10.
A review of the Oriental genus Cochinchinula Volk. (Coleoptera, Buprestidae, Polycestinae, Acmaeoderini) comprising three species is presented. The new species C. thailandica and C. bilyi spp. n. and the new genus Thaichinula gen. n. (type species T. ohmomoi sp. n.) from Thailand are described. A key to species of the genera Cochinchinula and Thaichinula is provided. The Nearctic genus Paracmaeoderoides Bellamy and Westcott is transferred from the subtribe Nothomorphina to the subtribe Acmaeoderoidina, and the South African genus Richtersveldia Bellamy is transferred from the subtribe Nothomorphina of Acmaeoderini to the tribe Ptosimini. The generic status is restored for another South African genus, Brachmaeodera Volkovitsh and Bellamy. The main evolutionary trends are discussed, and the taxonomic composition and classification of the tribe Acmaeoderini are clarified.  相似文献   

11.
Phylogenetic relationships among 26 South African species in the tribe Aphnaeini (Lepidoptera: Lycaenidae) were inferred from DNA characters of the mitochondrial gene cytochrome oxidase I (COI), using maximum-parsimony methods. The resulting phylogenetic estimate supports the systematic hypothesis made by Heath (1997, Metamorphosis, supplement 2), based on morphological characters, that at least three preexisting genera (Chrysoritis, Poecilmitis, and Oxychaeta) should be collapsed into the single monophyletic genus Chrysoritis. Two of the species groups described by Heath within Chrysoritis are also monophyletic, while one is paraphyletic and thus unsupported by the molecular data. Strong node support and skewed transition/transversion ratios suggest that two Chrysoritis clades contain synonymous species. Aphytophagy appears as a derived feeding strategy. Evolutionary patterns of ant association indicate lability at the level of ant genus, while association with different ant subfamilies may have played an ancestral and chemically mediated role in the diversification of South African aphnaeines.  相似文献   

12.
Among the 12 subfamilies currently considered in the systematics of Poaceae, the Arundinoideae have long been considered as a dustbin group, with a diversity of forms putatively hiding incertae sedis. Because this subfamily has been poorly investigated using molecular markers for the last two decades, the present study provides the first complete phylogeny of the Arundinoideae based on five plastid DNA loci sequenced for 12 genera, and analysed with and without plastome data from previous studies. The refined Arundinoideae appear to be a robust evolutionary lineage of Poaceae, divided into three tribes with some biogeographical patterns: (1) tribe Arundineae, the most heterogeneous tribe, including Eurasian Arundo, Australian Amphipogon and Monachather, and South African Dregeochloa; (2) tribe Crinipedeae (described here), including Crinipes, Elytrophorus, Styppeiochloa and Pratochloa (described here), with a South and East African distribution; and (3) tribe Molinieae, including Hakonechloa, Molinia and Phragmites, with a Eurasian distribution. Despite reduction in size, this small subfamily conserves a high diversity of morphological forms, with several small but highly differentiated genera. Finally, the molecular dating approach provides an evolutionary framework to understand the diversification of Arundinoideae, refuting Gondwanan vicariance between genera and suggesting capability for long distance dispersal.  相似文献   

13.
The buccal and lingual roots of 1077 teeth from 100 mandibles of South African Negroes were examined for the presence of dehiscences and fenestrae. All specimens were obtained from cadavers of known sex, tribe, and stated age; 10.5% of teeth were affected. Canines and first premolars were the most common teeth associated with dehiscences and fenestrae. Dehiscences occurred more commonly than fenestrae (1:0.49). The defects were found exclusively in the buccal plate of the alveolar process.  相似文献   

14.
The phylogenetic position ofAulotandra (Zingiberaceae).—Nord. J. Bot. 23 : 725–734. Copenhagen. ISSN 0107–055X.
Molecular data for 41 representatives of Zingiberaceae are analysed focusing on the phylogenetic position of Aulotandra and its relationship to Siphonochilus. Sequence divergences indicate that accessions of Aulotandra from Madagascar are closest to those of African Siphonochilus in both ITS and trnL-F data sets, indicating a close relationship. Together these genera form a highly supported monophyletic clade. This African-Madagascan lineage is sister to the rest of the family with African, Asian and South American members, showing that Aulotandra does not belong in the tribe Alpinieae, where it has been traditionally placed, but in the subfamily Siphonochiloideae with the genus Siphonochilus.  相似文献   

15.
Friis, I. & Wilmot-Dear, C.M. 1988. A revision of the tribe Forsskaoleae (Urticaceae). - Nord. J. Bot. 8: 25–59. Copenhagen. ISSN 0107–055X.
The tribe Forsskaoleae has been revised and the inflorescence and floral structure reinvestigated. The alternative interpretation of the flowers and inflorescences of Forsskaoleae proposed by Rivieres is rejected. A division of the tribe into two subtribes is tentatively maintained. The study of all genera is based on the total available material, with exception of Forsskaolea , of which only the types and some additional material have been studied, and an annotated survey of the six recognized species is presented. In Droguetia seven species are recognized, distributed from tropical and South Africa to Madagascar, the Mascarenes, Java, and India. An infrageneric division of the genus is not tenable. The genus Didymodoxa , for the last hundred years united with Australina , is reestablished with two species, both restricted to eastern and southern Africa. The genus Australina is, within the new delimitation, disjunct between Australia, Tasmania and New Zealand on the one hand and Ethiopia and Kenya on the other. In view of the considerable differences between them, each of the two species is placed in a separate section, sect. Australina and sect. Sarmentago . The lectotypification of Urtica capensis made by Prain is shown to be in conflict with the protologue; a new lectotype is selected, with consequence for the nomenclature of a South African Acalypha species (Euphorbiaceae). All taxa are keyed out and described; distribution maps and illustrations are provided for most taxa.  相似文献   

16.
The divergence date and ancestral distributional area of the psocid subfamily Speleketorinae, which includes taxa with reversed genitalia (female penis and male vagina of Afrotrogla and Neotrogla, tribe Sensitibillini), were estimated. The most basal divergence of the subfamily (between the North American Speleketor and the tribe Sensitibillini) was estimated to have occurred according to the separation between the North American continent and Gondwana, ca. 175 Ma. The most basal divergence of Sensitibillini (between African Afrotrogla + Sensitibilla and Brazilian Neotrogla) was estimated to have occurred according to the split of West Gondwana (separation between the African and South American continents), ca. 127 Ma. The biome of the ancestral distributional area of Sensitibillini (inland of West Gondwana) is believed to be arid to semi‐arid, which might strengthen the reversed sexual selection and then facilitate the origin of preadaptive features related to the evolution of a female penis. All extant Sensitibillini species inhabit carbonatic caves, but geological evidence suggested independent shifts of these genera to the carbonatic cave habitat in the Tertiary/Quaternary.  相似文献   

17.
Tribe Macadamieae (91 spp., 16 genera; Proteaceae) is widespread across the southern hemisphere on all major fragments of Gondwana except New Zealand and India. Macadamia is cultivated outside its natural range as a "nut" crop (notably in Hawaii, where it is the principal orchard crop). We sampled seven DNA regions and 53 morphological characters from the tribe to infer its phylogeny and address the common assumption that the distribution of the extant diversity of the tribe arose by the rafting of ancestors on Gondwanan fragments. Macadamia proves to be paraphyletic with respect to the African genus Brabejum, the South American genus Panopsis, and the Australian species Orites megacarpus. We erect two new generic names, Nothorites and Lasjia, to produce monophyly at that rank. The earliest disjunctions in the tribe are inferred to be the result of long-distance dispersal out of Australia (with one possible exception), rather than vicariance. Evolution of tardy fruit dehiscence is correlated with these dispersals, and the onset of the Antarctic Circumpolar Current (ACC) precedes them. We suggest that the ancestors of extant diversity arrived on their respective continents via the ACC, and we recognize that this is a mechanism precluded, rather than facilitated, by Gondwana's terrestrial continuity.  相似文献   

18.
Assmann T  Drees C  Matern A  Schuldt A 《ZooKeys》2011,(100):37-46
Eucamaragnathus desenderisp. n., a new ground beetle species of the tribe Hiletini, is described from eastern and southern Africa and dedicated to the recently deceased Belgian carabidologist Konjev Desender. The new taxon is known so far from localities in Zambia (Mukuku, southeast of Mansa) and in South Africa (Bothaville, south of Klerksdorp). The new species belongs to the Eucamaragnathus castelnaui group and is characterized by shape of pronotum, smooth or sparsely punctate pronotal transverse impression, characters of male genitalia and elytral striae continued to the apex. Illustrations of the habitus, the median lobe and its internal sac and several other morphological features are presented. An updated identification key to the African Eucamaragnathus species is given.  相似文献   

19.
Evidence from morphology is used to infer the phylogeny of the superfamily Poecilioidea using other cyprinodontoid fishes as outgroups. The three equally most parsimonious trees resulting from the phylogenetic analysis support the monophyly of the families Anablepidae and Poeciliidae with respect to each other, but the previous taxonomy within the Poeciliinae is not consistent with the resultant phylogenetic trees. The Poeciliidae is recognized with three subfamilies: the Aplocheilichthyinae containing solely Aplocheilichthys spilauchen , the Procatopodinae containing Fluviphylax (Fluviphylacini) and the African lamp-eyed killifishes (Procatopodini), and the Poeciliinae. The inferred hierarchical relationships of included suprageneric taxa are: ((Oxyzygonectinae, Anablepinae) (Aplocheilichthyinae ((Fluviphylacini, Procatopodini) (Alfarini (Priapellini (Gambusini (Heterandrini (Cnesterodontini (Girardini, Poeciliini))))))))). The tribe Alfarini is resurrected and a new tribe, the Priapellini, is described. Tomeurus gracilis is not the most basal poeciliine, and facultative viviparity in Tomeurus is not a plesiomorphic intermediate condition of viviparity retained from the common ancestor of poeciliines. Facultative viviparity in Tomeurus is the result of an evolutionary loss of obligate viviparity. Tomeurus gracilis is recognized as a member of the tribe Cnesterodontini. Lamprichthys tanganicus and Micropanchax pelagicus are not sister taxa, and the pelagic lacustrine habits of these two species are inferred to have evolved independently. Based on the principles of vicariance biogeography, the origin of the Poecilioidea is inferred to have occurred before the separation of Africa and South America.  相似文献   

20.
de Wet , J. M. J. (Div. Botany, Pretoria, So. Africa.) Chromosome numbers and some morphological attributes of various South African Grasses. Amer. Jour. Bot. 47(1): 44—49. Illus. 1960.– Chromosome numbers are reported for 68 species and varieties of grasses belonging to 40 genera. These include first reports for the genera Megastachya, Lintonia, Plagiochloa, Ctenium, Oropetium and Beckeropsis. Cytological data were correlated with observations from leaf and embryo anatomy. A common ancestor is postulated for the tribes Oryzeae, Ehrharteae and Centotheceae. The genera Lasiochloa, Plagiochloa and Urochlaena appear to belong neither with the tribe Festuceae nor with the Eragrosteae but probably are closer related to the Danthonieae. Lintonia. Entoplocamia, Tetrachne and Fingerhuthia are characterized by the chloridoid-eragrostoid type of cytology and leaf anatomy but the bambusoid type of embryo anatomy. For these reasons they appear to represent relics of the original Eragostoid and Chloridoid stock. The South African representatives of the genus Crinipes differ from the tropical species in respect to leaf anatomy. The tropical species are typically of the arundinoid type, whereas the South African species appear to be related to the Danthonieae.  相似文献   

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