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1.
The Campanulaceae s.s. have been proved to be monophyletic, but the subdivision of the family is still controversial among authors. To investigate the intrafamilial structure of the Campanulaceae s.s., four chloroplast DNA fragments, atpB, matK, rbcL, and petD with the petB-petD spacer region, were chosen for molecular phylogenetic analysis, and 90 taxa representing 36 genera of this family were sampled. The result shows that the Campanulaceae s.s. consist of three strongly supported monophyletic clades. This result is highly correlated with the data from palynology and external morphology. Therefore, we propose to establish a new three tribal classification system of Campanulaceae s.s. The Cyanantheae is characterized by colpate or colporate pollen with elongate apertures and a loculicidal capsule which is dehiscent by apical valves, or a berry. The other two tribes have porate pollen with poroid apertures, but the Campanuleae possesses a poricidal capsule which is dehiscent by lateral pores or valves, or a dry indehiscent fruit, whereas the Wahlenbergieae possesses a loculicidal capsule which is dehiscent by apical valves, pores, or opercula. In the Cyanantheae, we recognize 6 subtribes and 10 genera. In addition, keys to tribes of Campanulaceae s.s. and to subtribes and genera of the Cyanantheae are presented.  相似文献   

2.
The Mediterranean Basin harbors a remarkable amount of biodiversity, a high proportion of which is endemic to this region. Here, we present an in‐depth study of an angiosperm species complex, in which cryptic taxonomic diversity has been hypothesized. Specifically, we focus on four currently recognized species in the Roucela complex, a well‐supported clade in the Campanulaceae/Campanuloideae: Campanula creutzburgii, C. drabifolia, C. erinus, and C. simulans. This study takes a phylogenomic approach, utilizing near‐complete plastomes and 130 nuclear loci, to uncover cryptic diversity and test hypotheses regarding hybridization and polyploidy within this clade. Genome size estimates recovered tetraploid and octoploid lineages within the currently recognized, widespread species C. erinus, showing an east‐west geographic pattern. Though genomic data clearly differentiate these two cytotypes, we failed to discern morphological differences. The formation of a cryptic octoploid lineage, distributed across the eastern Mediterranean, is hypothesized to be the result of an allopolyploid event in which one parental morphology is retained. The tetraploid C. erinus and C. creutzburgii (also a tetraploid) are implicated as parental lineages. Our results highlight the utility of target‐enrichment approaches for obtaining genomic datasets for thorough assessments of species diversity and the importance of carefully considering gene‐tree discordance within such datasets.  相似文献   

3.
In this study, we examined the pollen morphology of the platycodonoid group in Campanulaceae s. str. using a scanning electronic microscope. We used pollen grains of 25 accessions representing 24 species of the Codonopsis complex (including Campanumoea, Cyclocodon, Leptocodon, and all three subgenera of Codonopsis), which is extremely controversial among authors for taxonomic treatment. Pollen morphology of all the other genera in the group observed by previous authors is taken into account in our discussion. A total of nine pollen types with two subtypes in the group were recognized and named for the first time. Molecular and morphological data imply that each pollen type corresponds to a natural group at generic level, and thus the mergence of Leptocodon with Codonopsis and the restoration of Cyclocodon as a separate genus are justifiable, and Codonopsis subg. Pseudocodonopsis, subg. Obconicicapsula, and two species of Codonopsis subg. Codonopsis (C. purpurea and C. chimiliensis) may be better classified as three independent genera separate from the core Codonopsis.  相似文献   

4.
Cicer L. (Leguminosae: Papilionoideae) consists of 42 species of herbaceous or semi-shrubby annuals and perennials distributed throughout the temperate zones of the Northern Hemisphere. The origin and geographical relationships of the genus are poorly understood. We studied the geographical diversification and phylogenetic relationships of Cicer using DNA sequence data sampled from two plastid regions, trnK / matK and trnS - trnG , and two nuclear regions, the internal transcribed spacer (ITS) and external transcribed spacer (ETS) regions of nuclear ribosomal DNA, from 30 species. The results from the phylogenetic analyses of combined nuclear and chloroplast sequence data revealed four well-supported geographical groups: a Middle Eastern group, a West-Central Asian group, an Aegean–Mediterranean group, and an African group. Age estimates for Cicer based on methods that do not assume a molecular clock (for example, penalized likelihood) demonstrate that the genus has a Mediterranean origin with considerable diversification in the Miocene/Pliocene epochs. Geological events, such as mountain orogenesis and environmental changes, are major factors for the dispersal of Cicer species. The early divergence of African species and their geographically distinct region in the genus suggest a broader distribution pattern of the genus in the past than at present.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 154 , 175–186.  相似文献   

5.
Phylogenetic analysis of plastid DNA restriction site and rearrangement mutations suggests a number of major revisions to taxonomy and phylogenetic concepts in the hard pines. Total genomic DNA from 18 species that sampled all nine subsections was digested with 19 restriction enzymes, blotted, and probed with 70% of the Douglas-fir (Pseudotsuga menziesii) chloroplast genome, or, with clones encompassing the entire chloroplast genome of Pinus contorta. A total of 204 site mutations and five rearrangement mutations were generated, of which 126 were phylogenetically informative. Wagner parsimony analyses revealed 11 clades that were strongly supported by bootstrap and decay index analyses. All North American species except P. resinosa formed a distinct monophyletic group that was strongly separated from the Eurasian species. Within the Eurasian clade subsect. Sylvestres was polyphyletic; its Mediterranean species were closely allied with members of sect. Pinea. Sect. Pinea appeared polyphyletic as well; both species of its subsect. Leiophyllae showed a close affinity to Mesoamerican pines of subsect. Oocarpae in sect. Pinus. Within the North American pines subsects. Ponderosae and Oocarpae were polyphyletic. Despite its shallow fossil record, subsect. Contortae emerged as a sister group to all of the North American pines apart from P. resinosa, which was allied with Eurasian species of subsect. Sylvestres. The remaining North American subsections formed two groups: a poorly resolved clade with subsects. Ponderosae and Sabinianae, and sequentially nested clades represented by: P. radiata; P. taeda; representatives of subsects. Oocarpae and Ponderosae from Mesoamerica, and subsect. Leiophyllae. We present estimates of divergence times for each of these major clades based on molecular clocks calibrated using two hard pine fossil observations.  相似文献   

6.
Earlier analyses ofrbcL sequences clarified phylogenetic relationships of 16 of 17 subfamilies ofSaxifragaceae s. l. This study investigates the affinities of the monotypicEremosynoideae, the only subfamily ofSaxifragaceae s. l. not examined previously forrbcL sequence variation. Our analyses suggest thatEremosyne is only distantly related to core members ofSaxifragaceae s. l. (i.e.Saxifragoideae = Saxifragaceae s. str.); it is allied instead with members ofAsteridae. A particularly close relationship is indicated betweenEremosyne andEscallonia, another traditional member ofSaxifragaceae s. l. that also appears as part ofAsteridae. Inclusion ofEremosyne withinAsteridae is in agreement with embryology, as well as with 18S rDNA sequence data.  相似文献   

7.
A survey of amplified fragment length polymorphism (AFLP) and chloroplast DNA (cpDNA) variation was conducted to elucidate the phylogeography of Campanula alpina , a key species of silicicolous alpine grasslands in the Carpathians with a disjunct distribution in the Eastern European Alps. The Carpathians experienced a different glacial history from the Alps: local glaciers were present only in the highest massifs, while alpine habitats extended over larger areas related to their present distribution in this region. We asked: (i) whether in the Carpathians a high-mountain plant exhibits a complex phylogeographical structure or rather signatures of recent migrations, and (ii) whether the disjunct part of the species' distribution in the Alps resulted from a recent colonization from the Carpathians or from a restricted expansion from separate Eastern Alpine refugia. Our study revealed a clear phylogeographical pattern in AFLPs supported by congruent groups of distinct cpDNA haplotypes. Highest genetic differentiation was observed between the Alps and the Carpathians, indicating a long-term isolation between populations from these two mountain ranges. Further genetic division within the Carpathians suggests that current species' distribution is composed of several groups which have been isolated from each other for a long period. One genetic break separates Western from Southeastern Carpathian material, which is in line with a classical biogeographical boundary. A further, strongly supported genetic group was identified at the southwestern edge of the Carpathian arch. In the Eastern Alps, genetic traces of glacial survival in separate refugial areas in the calcareous northern part and the siliceous central part were found.  相似文献   

8.
 Nuclear ribosomal (ITS) DNA sequence data from representatives of eleven out of 12 genera previously included in Thlaspi sensu lato were analyzed to elucidate relationships within the former genus Thlaspi sensu lato. Sequences from Thlaspi segregates Noccaea, Masmenia, Callothlaspi, Kotschyella, Microthlaspi, and Noccidium were added to the existing data sets, and only some Thlaspi sensu lato segregates formed a monophyletic group. The recently renamed genus Pseudosempervivum, formerly part of the genus Cochlearia, has been shown to be closely related to this group as well. Microthlaspi consists of three independent lineages of which Microthlaspi umbellatum is closely related to Neurotropis. The Thlaspi s.str. taxa including the type species T. arvense, are closely related to Peltaria and Alliaria and they represent a monophyletic group. Kotschyella and Noccidium, which were also integrated into Thlaspi s.l. are not closely related to any Thlaspi lineage. Therefore, we suggest major taxonomical changes which are not in agreement with concepts based on morphological data. Our ITS based phylogeny demonstrates that subtribe Thlaspidinae comprises some additional genera such as Teesdalia, Peltaria, and Alliaria, the latter two even previously classified in other tribes than tribe Lepidieae. Received August 15, 2000 Accepted January 30, 2001  相似文献   

9.
Cypella aquatilis is described as a new species of the Iridaceae, occurring in the Brazilian states of Rio Grande do Sul, Santa Catarina and Parana. The plant is remarkable by being submersed in streamlets and rivers, and by the vegetative proliferation in the inflorescence. Additionally, a new section, Nais , with C. aquatilis as the type species, and the new name C. exilis Ravenna to replace the illegitimate C. gracilis (Kl.) Bak. are proposed.  相似文献   

10.
The phylogenetic relationships of Hymenophyllum and its segregate genera Cardiomanes, Hymenoglossum, Rosenstockia, Serpyllopsis and Microtrichomanes are addressed, using 31 morphological characters of the sporophyte and one cytological character. As expected, this study reveals considerable morphological heterogeneity within the genus sensu lato, but several apomorphic changes allow support for some clades. Four unresolved taxa, Cardiomanes, Hymenoglossum, Diplophyllum and Mecodium pro parte are probably the most basal elements in Hymenophyllum. The analysis also suggests the polyphyly of Mecodium, and two unexpected associations: Sphaerocionium together with Microtrichomanes; and a broad clade composed of subg. Hymenophyllum, Hemicyatheon and Craspedophyllum, genera Rosenstockia and Serpyllopsis, and subsect. Leptocionium and Amphipterum. These associations appear justified by morphological, cytological or geographical data, and most of them are in agreement with preliminary molecular results.  相似文献   

11.
Two new sibling species, Larinus synthesys n. sp. from Algeria, and Larinus boroveci n. sp. from Algeria and Morocco, are described. Both species are tentatively assigned to the subgenus Larinus based on resemblance to species having longitudinal stripes on the elytra and rostrum. L. synthesys n. sp. is the smallest species in Larinus (s. str.) and is closely related to L. boroveci n. sp. The lectotype of Larinus cardopatii Lucas, 1847 is designated and redescribed. An illustrated key to the striped Larinus (s. str.) is given.  相似文献   

12.
 More than 100 accessions of Hordeum marinum ssp. marinum, ssp. gussoneanum 2x and ssp. gussoneanum 4x were studied by analyzing the nuclear DNA homologous to the chloroplast translation elongation factor. PCR amplification using the locus-specific primers generated a 932 bp fragment from ssp. marinum, a 915 bp fragment from ssp. gussoneanum 2x, and 915 bp and 931 bp fragments from ssp. gussoneanum 4x. Sequencing of the entire DNAs showed that the 915-bp fragments of diploids and tetraploids are identical, indicating that the diploid probably is the immediate donor of the 915-bp fragment of tetraploids. Although the donor of the 931-bp fragment was not determined, phylogenetic analysis of the data showed that the clade of the 931-bp fragment was included in the H. marinum complex. A MspI site was diagnostic to distinguish ssp. marinum into two clades with disjunct distributions, the Iberian Peninsula (type 2) and other regions (type 1). Nucleotide variation was revealed in the type 2 accessions but all the other clades were highly uniform. Received January 3, 1999 Accepted January 24, 2001  相似文献   

13.
Phylogenetic analyses of 18S rDNA sequences from 25 prasinophytes, including 10 coccoid isolates, reveals that coccoid organisms are found in at least three prasinophyte lineages. The coccoid Ostreococcus tauri is included in the Mamiellales lineage and P ycnococcus provasolii is allied with the flagellate P seudoscourfieldia marina. A previously undescribed prasinophyte lineage is comprised of the coccoid Prasinococcus cf. capsulatus (CCMP 1407) and other isolates tentatively identified as Prasinococcus sp. (CCMP 1202, CCMP 1614, and CCMP 1194), as well as three unnamed coccoids (CCMP 1193, CCMP 1413, and CCMP 1220). No flagellate organisms are known from this lineage. Organisms of this new lineage share some characteristics of both the Pycnococcaceae and the Mamiellales, although relationships among these separate lineages were not supported by bootstrap analyses. An additional unnamed coccoid isolate (CCMP 1205) is separate from all major prasinophyte lineages. The analyses did not resolve the relationships among the major prasinophyte lineages, although they support previous conclusions that the Prasinophyceae are not monophyletic.  相似文献   

14.
Abstract: This study aimed to test the monophyly and present a generic concept of Paxillus s. I. Of special interest were the Southern hemisphere representatives of this genus. Using the primer combination LR0R-LR5, DNA sequence data were generated from the nuclear encoded 28S gene. A data set containing 900 bases was created for 30 different species. Phylogenetic analysis showed 3 main monophyletic groups, also supported by morphological, anatomical, ecological and chemical data. Taxonomic interpretation of these clearly differentiated groups corresponded to the genera PaxilIus s. str. and Tapinella and lead to the proposal of a new Southern hemisphere genus, Austro-paxillus , mycorrhizal with Nothofagus . New combinations are proposed.  相似文献   

15.
Nothostele is a rare genus endemic to central Brazil. The taxonomy of the genus is controversial and almost every taxonomist has had a different point of view regarding its generic and subtribal classification. After the first collection 138 years ago, N. acianthiformis has been collected again and we report here a phylogenetic analysis of the genus based on nuclear ribosomal internal transcribed spacer and plastid matK and trnLtrnF sequence data. Our results show that Nothostele belongs to subtribe Spiranthinae and is sister to Eltroplectris within the Stenorrhynchos clade. A reanalysis of gynostemium morphology shows that the presence of a hamulus was misinterpreted in Nothostele and that the placement of the genus in Cranichidinae based on morphology of the pollinarium is unwarranted. Furthermore, the flattened, sessile, prostrate leaves of N. acianthiformis, which are described here for the first time, occur in some Spiranthinae but are atypical in Cranichidinae. Specimens from Brasília in the Brazilian central plateau are a distinct new species, which is described here as N. brasiliaënsis. Currently, the genus comprises two disjunct species restricted to the cerrado and rocky field vegetation of central Brazil. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 348–363.  相似文献   

16.
BACKGROUND AND AIMS: The discovery of a new species, Haplophyllum bastetanum F.B. Navarro, V.N. Suárez-Santiago & Blanca sp. nov., in the south-east of Spain has prompted the comparative study of species of the Iberian Peninsula, and others related, through morphological, cytogenetic, molecular, distributional and ecological characterization. METHODS: The morphological study involved a quantitative analysis of the species present in the Iberian Peninsula and a comparative analysis of the morphological characteristics between H. bastetanum and other related species. Mitotic analyses were made with root meristems taken from germinating seeds. Phylogenetic analyses of the internal transcribed spacer sequences of nuclear ribosomal DNA were performed using neighbour-joining (NJ) and maximum-parsimony methods. KEY RESULTS: Haplophyllum bastetanum is a diploid species (2n = 18) distinguished primarily for its non-trifoliate glabrous leaves, lanceolate sepals, dark-green petals with a dorsal band of hairs, and a highly hairy ovary with round-apex locules. The other two Iberian species (H. linifolium and H. rosmarinifolium) are tetraploid (2n = 36) and have yellow petals. Both phylogenetic methods generated a well-supported clade grouping H. linifolium with H. rosmarinifolium. In the NJ tree, the H. linifolium-H. rosmarinifolium clade is a sister group to H. bastetanum, while in the parsimony analysis this occurred only when the gaps were coded as a fifth base and the characters were reweighted according to the rescaled consistency index. This latter group is supported by the sequence divergence among taxa. CONCLUSIONS: The phylogenies established from DNA sequences together with morphological and cytogenetic analyses support the separation of H. bastetanum as a new species. The results suggest that the change in the number of chromosomes may be the key mechanism of speciation of the genus Haplophyllum in the Iberian Peninsula. An evolutionary scheme for them is propounded.  相似文献   

17.
Phylogenetic analyses within Poaceae tribe Poeae subtribes Puccinellinae (=Coleanthinae), Phleinae, Poinae s.l. (including Alopecurinae), and Miliinae (PPAM clade), revealed that one species formerly placed in Poa represents a new monotypic genus belonging to subtribe Poinae s.l., Dupontiopsis gen. nov., D. hayachinensis comb. nov. (based on Poa hayachinensis), endemic to wet, gravelly, serpentine, alpine habitats in northern Japan. This genus forms a strongly supported clade (DAD) with two circumarctic Poinae genera, Arctophila and Dupontia, in phylogenetic analyses of plastid and nuclear ribosomal DNA sequence data. Both morphology and DNA sequence analyses provide support for D. hayachinensis as a lineage distinct from either Arctophila or Dupontia, with moderate DNA support for a position as sister to these two genera. Dupontiopsis resembles these other monotypic genera in its several-flowered spikelets, lemmas usually 3-nerved, with frequently awned attenuate scarious apices (as in Dupontia) and calluses with a crown of hairs around the base of the lemma, but differs in its keeled lemmas, scabrous palea keels, glumes shorter than the first lemma. Our investigation suggests that the most recent shared ancestor of the DAD clade evolved from a single hybridization event, as a hexaploid, probably in western Beringia. The probable parentage of the ancestor is considered to be within the Poinae–Alopecurinae clade excluding Poa. We provide evidence for possible secondary hybridization and introgression of duodecaploid Dupontia fisheri with Puccinellia. A key to perennial genera of PPAM with hairy calluses, and a supplemental table of morphological characters in the genera accepted in PPAM are provided.  相似文献   

18.
Southern Africa is one of the hot spots for plant biodiversity, with ca. 80% of species endemic to this area. Rapid and recent radiations in Southern African plant genera were triggered by fine-scale differences in climate, topography and geology. The genus Lithops (Ruschioideae, Aizoaceae) contains 37 species and is widely distributed in Southern Africa. Species delimitation within the genus is challenging because the limited number of morphological characters in these reduced succulents varies intensely between populations, presumably as adaptations to local geological environments. We analysed phylogenetic relationships within Lithops using non-coding chloroplast DNA (trnS-trnG intergenic spacer), nuclear ribosomal internal transcribed spacer (nrITS) sequences and AFLP data. Genetic variability of the sequence data was very low, but AFLP data detected nine clades within Lithops that do not fit current morphology-based taxonomy. Two of these clades are separated by their distribution on the northern and eastern border of the distribution area, and four clades are found in the Gariep Centre in the estuary of the Orange River. Morphological similarities, especially colour of leaves, evolved repeatedly within the clades, thus we hypothesise that closely related species became adapted to different soil types in a mosaic-like geological environment. One-third of the species are found in the Gariep Centre, characterised by extremely diverse edaphic habitats.  相似文献   

19.
Historical relationships were inferred for the oriental lizards of the genus Takydromus Daudin 1802 (Lacertidae) on the basis of DNA sequences. Of the 17 species currently recognized for the genus, 13 species represented by 42 specimens from 29 localities were examined. Maximum-likelihood and maximum-parsimony analyses of data for 829 aligned sites from parts of the mitochondrial 12S and 16S rRNA genes yielded relationships that, while showing no substantial discrepancy with each other, were strikingly different from a currently prevailing phylogenetic hypothesis from a parsimony analysis of morphological characters. Based on the results of these molecular analyses, supplemented by results of the morphological analysis that offered robust evidence for positions of two additional species ( T. khasiensis and T. sylvaticus ), the following interrelationships were hypothesized as the most preferred phylogeny: ( kuehnei ( sexlineatus khasiensis ))( tachydromoides (( smaragdinus ( sauteri ( dorsalis sylvaticus ))) ( amurensis ((( formosanus wolteri ) hsuehshanensis )( toyamai ( septentrionalis stejnegeri )))))). These interrelationships indicate: (1) invalidity of Platyplacopus Boulenger 1917 , which was recently resurrected as a subgenus of Takydromus on the basis of the morphological analysis; (2) homoplasy in states of some morphological characters, such as green dorsal coloration, that were considered as synapomorphs of certain nodes in the morphological analysis; and (3) involvement of the genus in a series of vicariances in both the continental and insular parts of eastern Eurasia. Due to the paucity of available samples, phylogenetic status of T. intermedius and T. haughtonianus remain to be examined in future studies.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 76 , 493–509.  相似文献   

20.
A phylogenetic analysis of the interrelationships of the barbets (Capitonidae) and the toucans (Aves: Ramphastidae, Superfamily Ramphastoidea) is presented. Thirty-two morphological characters from the literature and independent osteological observations were analysed. Character polarity was determined by outgroup comparison to the Picidae, Indicatoridae, Galbulidae, Bucconidae and Coraciiformes. Four alternative phylogenetic hypotheses were compared: (1) the overall most parsimonious morphological phylogeny, (2) the most parsimonious morphological phylogeny in which the capitonids and ramphastids were hypothesized as monophyletic sister groups, and (3) and (4) the most parsimonious hypotheses for the evolution of the morphological characters within two proposed DNA-DNA hybridization phylogenies of the ramphastoids. The analysis focused on the higher level relationships of ramphastids and capitonids and interrelationships among capitonid genera. Two cladistic analyses were performed using 26 phylogenetically informative characters, and the PAUP and CONTREE computer alogorithms. The most parsimonious morphological phylogeny required fewer character changes and had a lower consistency index than any of the alternative hypotheses but congruence between the most parsimonious phylogeny and the second, revised DNA-DNA hybridization hypothesis was very high. Based on these results the monophyly of the Capitonidae is rejected. The ramphastids and the Neotropical capitonids form a well corroborated clade within the pantropical ramphastoid radiation. Neither the African, Asian nor New World capitonids is monophyletic. The genus Trachyphonus is the sister group to all other capitonids and ramphastids. The sister group to the ramphastids is the genus Semnornis. The interrelationships of the Old World capitonids excluding Trachyphonus are not completely resolved by these morphological data but one of the alternative phylogenetic resolutions is presented as a preliminary hypothesis. The clades in this resolved phylogeny are diagnosed and the palaeontology and biogeography of the ramphastoids arc-reviewed in light of this new evidence. A phylogenetic classification is proposed in which the Capitonidae is rejected and the capitonids and ramphastids are placed in seven subfamilies of the Ramphastidae.  相似文献   

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