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1.
Phylogenetic relationships within the tribe Antirrhineae (Scrophulariaceae) are analysed and discussed on the basis of parsimony analyses of morphological andndhF gene sequence data. The results indicate that the tribe Antirrhineae consists of four major groups of genera, theAnarrhinum clade, theGambelia clade, theMaurandya clade, and theAntirrhinum clade. TheAnarrhinum clade, consisting of the Old World bee-pollinated generaAnarrhinum andKickxia, is sister to the rest of the tribe. TheGambelia clade consists of the New World generaGambelia andGalvezia, which are very closely related and pollinated by hummingbirds. TheMaurandya clade consists of one subclade includingMaurandya and a number of related bee- or hummingbird-pollinated New World genera and another subclade with the Old World bee-pollinated generaAsarina andCymbalaria. TheAntirrhinum clade consists mainly of bee-pollinated Old World genera, such asAntirrhinum, Linaria, Chaenorhinum, and their segregates, but also includes the New World generaMohavea andHowelliella, of which the latter is known to be partly pollinated by hummingbirds. It is concluded that hummingbirdpollination has evolved independently within Antirrhineae at least three times from bee-pollinated ancestors.  相似文献   

2.
Total DNA was extracted from 55 species of theLeguminosae (including 29 species ofLupinus). The chloroplast generbcL and the ITS 1 + 2 regions of nuclear RNA genes were amplified by polymerase chain reaction (PCR) and sequenced directly. The sequences obtained were evaluated with character state (Maximum Parsimony) and distance methods (Neighbour Joining). Phylogenetic trees obtained with both data sets and methods are mostly congruent.Genisteae andCrotalarieae are sister groups and share ancestry with theThermopsideae/Podalyrieae. The genusLupinus, which forms a monophyletic clade within theGenisteae, shows a distinct Old-New World disjunction and appears to be divided into several more or less distinct groups: (1) The species from the eastern part of South America. (2) The homogeneous rough-seeded group (Scabrispermae) of the Old World species which is well distinguished from the smooth-seeded group (Malacospermae). (3) Within the rather heterogeneous smooth-seeded lupins a smaller subgroup withL. angustifolius, L. hispanicus andL. luteus is recognized. (4) Also separated are North American lupins and South American species with a western distribution. Genetic distances imply that the genusLupinus evolved during the last 12–14 million years, ruling out the hypothesis that the present Old-New World disjunction can be interpreted as a result of the continental drift. The genetic data suggest an origin in the Old World and an independant colonisation of the Eastern parts of South America as opposed to North America and the Western parts of South America.  相似文献   

3.
We present the first parsimony analyses of the Neotropical family Quiinaceae using nucleotide sequence data from the non-coding trnL intron and trnL-trnF intergenic spacer of the plastid genome, analysed separately as well as in combination with morphology. Both molecules and combined data recover Quiinaceae as a well-supported monophyletic group. Quiinaceae form a polytomy together with their potential sister groups, the monophyletic Ochnaceae s.str. and the monotypic Medusagynaceae from the Seychelles in the Indian Ocean. Froesia is resolved as sister to the rest of the family. Other members of the family, Lacunaria, Quiina, and Touroulia, are all recovered as monophyletic despite the inclusion of strikingly distinctive representatives (L. oppositifolia and Q. pteridophylla). Relationships among the last three genera, however, are yet uncertain. Optimising characters of breeding system onto the molecular phylogeny reveals that bisexual flowers (Froesia) are the ancestral state in Quiinaceae, whereas androdioecy (Quiina, Touroulia) and dioecy (Lacunaria) are derived breeding systems.  相似文献   

4.
The phylogeny of Celastraceae tribe Celastreae, which includes about 350 species of trees and shrubs in 15 genera, was inferred in a simultaneous analysis of morphological characters together with nuclear (ITS and 26S rDNA) and plastid (matK, trnL-F) genes. A strong correlation was found between the geography of the species sampled and their inferred relationships. Species of Maytenus and Gymnosporia from different regions were resolved as polyphyletic groups. Maytenus was resolved in three lineages (New World, African, and Austral-Pacific), while Gymnosporia was resolved in two lineages (New World and Old World). Putterlickia was resolved as nested within the Old World Gymnosporia. Catha edulis (qat, khat) was resolved as sister to the clade of Allocassine, Cassine, Lauridia, and Maurocenia. Gymnosporia cassinoides, which is reportedly chewed as a stimulant in the Canary Islands, was resolved as a derived member of Gymnosporia and is more closely related to Lydenburgia and Putterlickia than it is to Catha. Therefore, all eight of these genera are candidates for containing cathinone- and/or cathine-related alkaloids.  相似文献   

5.
We used ITS and trnL sequence data, analyzed separately and combined by MP, to explore species relationships and concepts in Trema (Celtidaceae), a pantropical genus of pioneer trees. Whether Trema is monophyletic or includes Parasponia is still unresolved. Three clades within Trema received moderate to high support, one from the New World and two from the Old World, but their relationships were not resolved. In the New World, specimens of T. micrantha formed two groups consistent with endocarp morphology. Group I, with smaller brown endocarps, is a highly supported clade sister to T. lamarckiana. Group II, with larger black endocarps, is poorly resolved with several subclades, including the highly supported T. integerrima clade. Both Old World clades contain Asian and African species, with three or more species in each region. Trema orientalis is not monophyletic: specimens from Africa formed a highly supported clade sister to T. africana, while those from Asia were sister to T. aspera from Australia.  相似文献   

6.
Several types of pollinium stalk are present in theCorallorhizinae. Govenia has a cellular epidermal pollinium stalk, whileTipularia has a unique stipe that results from prolongation and detachment of the rostellum.Dactylostalix andEphippianthus have no stipe, but do have a detachable viscidium.Aplectrum, Corallorhiza, Cremastra, andOreorchis have hamuli. Cladistic analysis of morphological characters suggests that these four genera form a coreCorallorhizinae, and are sister group to a clade includingTipularia, Calypso, andYoania (the latter two possessing a true tegula).Govenia is shown to be most closely related to cymbidioid genera (such asEulophia), sharing with them the cellular epidermal pollinium stalk andCymbidium type velamen, and indicating that removal ofGovenia fromCorallorhizinae is appropriate.Dactylostalix andEphippianthus appear to occupy a more basal position in the subfamily, further arguing that the subtribe as previously recognized is paraphyletic.  相似文献   

7.
The placement of a recently discovered South American monotypic genus,Pseudomonotes tropenbosii, in subfam.Monotoideae (Dipterocarpaceae) extends the geographical range of the subfamily from Africa to the Neotropics. Although morphological and anatomical evidence suggest similarities betweenPseudomonotes andMonotes, the close alliance of these two genera was questionable due to their disjunct distribution and a lack of phylogenetic analysis. In the present study, we reconstructed the phylogeny ofPseudomonotes and other putatively related taxa usingrbcL sequence data. The analysis ofrbcL sequences of 20 taxa belonging to 15 genera and eight families recovered a single most parsimonious tree. The genusSarcolaena (Sarcolaenaceae) formed a clade sister to the monophyleticDipterocarpaceae clade.Monotes andPseudomonotes formed a strongly supported group, sister to the monophyletic clade withPakaraimaea and the remaining Asiatic dipterocarp species studied. The study strongly supports the placement ofPseudomonotes within subfam.Monotoideae of theDipterocarpaceae.  相似文献   

8.
Extant bats of the genus Emballonura have a trans-Indian Ocean distribution, with two endemic species restricted to Madagascar, and eight species occurring in mainland southeast Asia and islands in the western Pacific Ocean. Ancestral Emballonura may have been more widespread on continental areas, but no fossil identified to this genus is known from the Old World. Emballonura belongs to the subfamily Emballonurinae, which occurs in the New and Old World. Relationships of all Old World genera of this subfamily, including Emballonura and members of the genera Coleura from Africa and western Indian Ocean islands and Mosia nigrescens from the western Pacific region, are previously unresolved. Using 1833 bp of nuclear and mitochondrial genes, we reconstructed the phylogenetic history of Old World emballonurine bats. We estimated that these lineages diverged around 30 million years ago into two monophyletic sister groups, one represented by the two taxa of Malagasy Emballonura, Coleura and possibly Mosia, and the other by a radiation of Indo-Pacific Emballonura, hence, rendering the genus Emballonura paraphyletic. The fossil record combined with these phylogenetic relationships suggest at least one long-distance dispersal event across the Indian Ocean, presumably of African origin, giving rise to all Indo-Pacific Emballonura species (and possibly Mosia). Cladogenesis of the extant Malagasy taxa took place during the Quaternary giving rise to two vicariant species, E. atrata in the humid east and E. tiavato in the dry west.  相似文献   

9.
Coleeae (Bignoniaceae) are a tribe almost entirely restricted to Madagascar. Coleeae have previously been placed in neotropical Crescentieae due to species with indehiscent fruits, a character otherwise unusual in Bignoniaceae. A phylogeny based on three chloroplast regions (ndhF, trnT-L spacer, trnL-F spacer) identifies a monophyletic Coleeae that is endemic to Madagascar and surrounding islands of the Indian Ocean (Seychelles, Comores and Mascarenes). African Kigelia is not a member of Coleeae, rather it is more closely related to a subset of African and Southeast Asian species of Tecomeae. The molecular phylogeny indicates that indehiscent fruit have arisen repeatedly in Bignoniaceae: in Coleeae, Kigelia and Crescentieae. The characteristic fleshy fruits of species of Coleeae likely arose autochthonously in Madagascar. Within Coleeae Colea and Ophiocolea are sisters, Phyllarthron is sister to Colea + Ophiocolea, and Rhodocolea is sister to the rest of the tribe.  相似文献   

10.
Lithospermum (Boraginaceae) comprises approximately 40 species in both the Old and New Worlds, with a center of diversity in the southwestern United States and Mexico. Using ten cpDNA regions, a phylogeny of Lithospermum and related taxa was reconstructed. Lithospermum (including New World and Old World species) and related New World members of Lithospermeae form a monophyletic group, with Macromeria, Onosmodium, Nomosa, Lasiarrhenum, and Psilolaemus nested among species of Lithospermum. New World Lithospermeae also is a monophyletic group, with Eurasian species of Lithospermum sister to this group. Because Lithospermum is not monophyletic without the inclusion of the other New World genera, species from these genera are transferred to Lithospermum, and appropriate nomenclatural changes are made. New combinations are Lithospermum album, Lithospermum barbigerum, Lithospermum dodrantale, Lithospermum exsertum, Lithospermum helleri, Lithospemum leonotis, Lithospermum notatum, Lithospermum oaxacanum, Lithospermum pinetorum, Lithospermum rosei, Lithospermum trinverium, and Lithospermum unicum; new names are Lithospermum chiapense, Lithospermum johnstonii, Lithospermum macromeria, Lithospermum onosmodium, Lithospermum rzedowskii, and Lithospermum turneri.  相似文献   

11.
A phylogeny of Packera is presented based on sequence data from the internal transcribed spacer region of nuclear ribosomal DNA of 26 species (28 populations) of Packera and 23 outgroup taxa, including representatives of all three subtribes of the Senecioneae. The results support a Mexican origin for Packera, with its closest relatives found among Old World taxa in the subtribe Senecioninae, such as Senecio jacobaea and Pericallis. Packera species from the west coast of the United States, previously included in the section Bolanderi of Greenman, are part of a basal assemblage including species of Greenman's Mexican section Sanguisorboidei. The rest of Packera separates into two sister groups, one containing species from the Arizona-New Mexico region and the other containing more geographically diverse taxa. Among the outgroups, New World Senecio species are monophyletic and two Tussilaginoid assemblages are strongly supported; the Tephroseroid group (Tephroseris and Sinosenecio) plus Petasites combine with the Luina complex to form a clade of north temperate taxa, and the four Mexican genera (Psacalium, Robinsonecio, Barkleyanthus, and Pittocaulon) form a monophyletic group.  相似文献   

12.
Recent molecular studies on passerine birds have highlighted numerous discrepancies between traditional classification and the phylogenetic relationships recovered from sequence data. Among the traditional families that were shown to be highly polyphyletic are the Muscicapidae Old World flycatcher. This family formerly included all Old World passerines that forage on small insects by performing short sallies from a perch. Genera previously allocated to the Muscicapidae are now thought to belong to at least seven unrelated lineages. While the peculiarity of most of these lineages has been previously recognized by Linnean classification, usually at the rank of families, one, the so-called Stenostiridae, a clade comprising three Afrotropical and Indo-Malayan genera, has only recently been discovered. Here, we address in greater detail the phylogenetic relationships and biogeographic history of the Stenostiridae using a combination of mitochondrial and nuclear data. Our analyses revealed that one species, Rhipidura hypoxantha, previously attributed to the Rhipiduridae (fantails), is in fact a member of the Stenostiridae radiation and sister to the South African endemic genus Stenostira (Fairy Flycatcher). Our dating analyses, performed in a relative-time framework, suggest that the splits between Stenostira/R. hypoxantha and Culicicapa/Elminia occurred synchronously. Given that the Stenostiridae assemblage has been consistently recovered by independent studies, we clarify its taxonomic validity under the rules of the International Code of Zoological Nomenclature.  相似文献   

13.
The Hamamelidaceae is a family that bridges the basal elements of the Rosidae and the lower Hamamelidae, thus a better understanding of the phylogeny of the family is important for clarifying evolutionary patterns in the diversification of eudicots. However, subfamilial as well as tribal relationships in the Hamamelidaceae have been controversial. Nucleotide sequences of the chloroplast genematK were used to study the intergeneric relationships of the family. In the phylogenetic trees, constructed using parsimony analysis, the clade containingAltingia andLiquidambar (Altingioideae) is sister to a clade that includes all other Hamamelidaceae.Exbucklandia andRhodoleia form a clade, suggesting a close relationship between the two genera.Disanthus is sister to the monophyletic Hamamelidoideae. The paraphyletic arrangement ofDisanthus, Mytilaria andExbucklandia with respect to the Hamamelidoideae does not support the combination of these genera in one subfamily. In the Hamamelidoideae, thematK phylogeny supports the monophyly of several previously recognized groups with modifications, including the tribes Eustigmateae (incl.Molinadendron), Fothergilleae (excl.Molinadendron andMatudaea), and the subtribe Dicoryphinae. However, the Hamamelideae as traditionally circumscribed is polyphyletic. Apetaly has evolved three times independently in the Hamamelidoideae.  相似文献   

14.
Chloroplast DNA restriction site variation was examined for 35 taxa in theVernonieae and four outgroup tribes, using 17 restriction enzymes mapped for ca. 900 restriction sites per species; 139 mutations were found to be phylogenetically informative. Phylogenetic trees were constructed using Wagner and weighted parsimony, and evaluated by bootstrap and decay analyses. Relationships of Old and New World taxa indicate complex geographical relationships; there was no clear geographic separation by hemisphere. The relationships between Old and New World Vernonias found here support prior morphological analyses. The sister group to all New and most Old World taxa was composed of a small group of Old World species including yellow-flowered, trinervate-leaved species previously postulated to be basal in the tribe. The majority of both New and Old World taxa are derived from a lineage beginning with the monotypic genusStokesia, an endemic of the southeastern United States. The genusVernonia was also found to be paraphyletic within both the New and Old World. Available data do not support either the separation ofVernonia or the tribeVernonieae into geographically distinct lineages. The pattern of relationships within theVernonieae for taxa from North America, Asia, Africa, Central and South America is most similar to that of several other groups of both plants and animals with a boreotropical origin, rather than an origin in Gondwanaland. Such a pattern of distribution suggests more ancient vicariant events than are routinely postulated for theAsteraceae.  相似文献   

15.
The phylogenetic relationships of the angiosperm generaByblis andRoridula have been the subject of ongoing taxonomic controversy. Twenty-eight taxa of varying degrees of alleged relationship, including 3 members of theWinteraceae (as an outgroup), were investigated using partial sequences of 18S rRNA (small subunit) and also compared against the morphological data set fromHufford's (1992) cladistic treatment of 80 members of theRosidae-Asteridae. The morphological analysis placed the two genera in a clade with theSarraceniaceae in theCorniflorae-Asterid group as a sister taxon to anEricales-Hydrangeales clade. The 18S rRNA analysis supports the recently publishedrbcL DNA analysis ofAlbert & al. (1992), withRoridula joined to taxa in the lowerRosidae, butByblis joining instead to members of theAsteridae near theSolanaceae. Comparisons for congruence between the three analyses placeByblis in the higher Asterid group near theSolanaceae, andRoridula possibly nearer theSarraceniaceae andEricales. These results imply that the traditional morphological characters used to relate the two genera are possibly the result of convergence towards similar ecological and life-history strategies rather than synapomorphies.  相似文献   

16.
Andrew Henderson 《Brittonia》1999,51(1):106-113
The Euterpeinae contains six neotropical genera. There has been continual disagreement on generic and subgeneric boundaries in the subtribe.Euterpe andPrestoea, andJessenia andOenocarpus, have been repeatedly united and separated. A phylogenetic analysis based on 54 morphological and anatomical characters gave one tree of 127 steps.Euterpe is separate fromPrestoea, butJessenia andOenocarpus are best treated as one genus. Subgeneric relationships ofEuterpe andOenocarpus are also analyzed and discussed.  相似文献   

17.
A cladistic study ofDipsacaceae (Asteridae, Dipsacales) was undertaken, based mainly on morphological and palynological characters, obtained by investigations of herbarium material and from the literature. Outgroups includedMorinaceae, Triplostegiaceae, and a subset ofValerianaceae. The consensus tree resulting from three equally parsimonious cladograms shows thatDipsacaceae are divided into two major clades, one withDipsacus andCephalaria, the other including the remaining genera. Within the latter clade,Knautia is the sister group of the rest of the taxa. This study is a reappraisal ofDipsacaceae phylogeny, and the results broadly match previous evidence.  相似文献   

18.
The complex distributions of morphological character states in the Indo-Pacific palm tribe Areceae (Arecaceae; Arecoideae) are potentially challenging for the delimitation of its genera. In the first exhaustive sampling of all 65 genera of the Areceae, we examined relationships of two of the tribe's most problematic genera, Heterospathe and Rhopaloblaste, using portions of the low-copy nuclear genes phosphoribulokinase (PRK) and RNA-polymerase II subunit B (RPB2). Both genera fell within a highly supported clade comprising all Areceae genera, but are clearly unrelated. Rhopaloblaste was strongly supported as monophyletic and is most closely related to Indian Ocean genera. Heterospathe was resolved with strong support within a clade of western Pacific genera, but with the monotypic Alsmithia nested within it. Ptychosperma micranthum, which has previously been included in both Heterospathe and Rhopaloblaste, is excluded from these and from Ptychosperma, supporting its recent placement in a new genus Dransfieldia. Morphological comparisons indicate that the crownshaft is putatively synapomorphic for the Areceae with numerous reversals within the clade and some independent origins elsewhere. The putative diagnostic characters of Heterospathe show high levels of homoplasy, and the genus can only be distinguished by a suite of characters, whereas Rhopaloblaste is more clearly defined. Our results have implications not only for the two genera in focus, but have also been influential for the new classification of the Areceae.  相似文献   

19.
A phylogenetic analysis of 25 species, representing eight genera of theRubieae tribe (Rubiaceae), has been made using the DNA sequence of the chloroplastatp B-rbc L intergene region. Six tropical genera from other tribes ofRubiaceae have been used as outgroups. Whatever the method of analysis (distance, parsimony or maximum likelihood), five groups are clearly separated and described as informal clades. Their relative relationships are not clearly resolved by the parsimony analysis, resulting in eight equally parsimonious trees, 327 steps long, with a consistency index (CI) of 0.749 (excluding uninformative sites). TheRubieae tribe appears monophyletic from the data available. Some new and partly unexpected phylogenetic relationships are suggested. The genusRubia forms a separate clade and appears to be the relatively advanced sister group of the remaining taxa. TheSherardia clade also includes the generaCrucianella andPhuopsis. Galium sect.Aparinoides appears closely attached to theAsperula sect.Glabella clade. The remaining taxa ofGalium are paraphyletic:Galium sect.Platygalium (in theCruciata clade) is linked to the advanced generaCruciata andValantia; the more apomorphic groups ofGalium form theGalium sect.Galium clade, including the perennial sectionsGalium, Leiogalium, andLeptogalium as well as the annual (and possibly polyphyletic) sect.Kolgyda.  相似文献   

20.
Complete sequences for the 18S-rRNA gene of 22 bryophytes (12 completely new) were determined and used to construct phylogenetic trees. The evaluation of sequence data according to the maximum parsimony principle (PAUP 3.1.1) and the neighbor-joining method (MEGA) results in similar phylogenetic trees in which theBryopsida appear as a sister group to theJungermanniopsida, and both together as a sister group to theMarchantiopsida. Among theMarchantiopsida, theSphaerocarpales diverge early as a separate clade. TheMetzgeriales andJungermanniales are monophyletic. They belong to one clade and cannot be separated by either method of evaluation.  相似文献   

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