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1.
The pollen of 32 species of Lysipomia was examined by light, scanning, and transmission electron microscopy. Two pollen types occur in the genus: 3-colporate and
6-colporate. The 3-colporate condition occurs in only two species, L. laciniata and L. pumila. The remaining 30 species are 6-colporate, a condition known from only one other genus in the Campanulaceae. Surface sculpturing
among the species is uniformly striate. Pollen shape was highly variable within a single individual in comparisons of pollen
gathered from herbarium specimens, FAA preserved material collected in the field, and fresh pollen from cultivated individuals
grown from seed. Shape may change from oblate spheroidal to subprolate as a result of drying time and temperature, and should
not be used as a morphological character in systematic studies if infraspecific variation is seen. When fresh or preserved
pollen is not available, rehydrated pollen should be compared to reduce the possibility of inadvertent artifact production
confounding the analysis of morphological data. 相似文献
2.
Thomas G. Lammers 《Brittonia》2009,61(2):126-143
Trematolobelia (Campanulaceae: Lobeliodeae) is a genus of semelparous pliestesial pachycaul rosette treelets endemic to the Hawaiian Islands. Eight species are re-cognized. The most widespread is T. macrostachys, found in the Ko‘olau Mountains of O‘ahu and on Moloka‘i and Maui. The remainder are single-island endemics: T. auriculata (Lna‘i); T. grandiflora (Hawai‘i); T. kaalae, comb. et stat. nov. (Wai‘anae Mountains of O‘ahu); T. kauaiensis (Kaua‘i); T. rockii (Moloka‘i); T. singularis (Ko‘olau Mountains of O‘ahu); and T. wimmeri (Hawai‘i). 相似文献
3.
Thomas G. Lammers 《Brittonia》1998,50(2):233-262
Burmeistera, Centropogon, and Siphocampylus together comprise more than 500 species endemic to the Neotropics, Current knowledge of these genera is unsatisfactory, with
much diversity yet to be described. Over the past seven years, one out of every 28 specimens received for identification has
represented a new species, many characterized by unique or unusual character states. Siphocampylus smilax (Bolivia) is unique in the genus in its parallelodromous leaf venation and extra-floral nectaries. Centropogon dianae (Peru) cannot be accommodated in any recognized infrageneric taxon, and a new section, Centropogon sect. Niveopsis, is proposed for it. The flowers of C. steinii (Ecuador) are the smallest known in the genus, while C. connatilobatus (Venezuela) is the first species to combine arbusculiform pubescence and connate calyx lobes. Burmeistera venezuelensis is only the second species of the genus known to occur in Venezuela and the first to be endemic; similarly, Centropogon wilburii is only the third species of Centropogon known from Mexico and the first to be endemic to that country. Additional novelties are also described. 相似文献
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Young -Dong Kim Joonku Lee Youngbae Sun Sangtae Lee Sung -Hee Kim Robert K. Jansen 《Journal of Plant Biology》1999,42(2):168-173
The phylogenetic relationship of the Korean endemic genus,Hanabusaya, to other campanulaceous genera has been controversial since it was described by Nakai in 1911. Three genera of Campanuloideae,Symphyandra, Adenophora, andCampanula, have been considered closely related by various taxonomists on the basis of anther shape, gross morphology, and pollen characters, respectively. We have tested these competing taxonomic hypotheses using the internal transcribed spacer (ITS) sequences of nuclear ribosomal DNA from 12 taxa representing 7 genera of Campanulaceae. The molecular phylogeny indicates strongly thatHanabusaya is more closely allied toAdenophora than toCampanula orSymphyandra. The phylogenetic affinity ofHanabusaya andAdenophora is supported by a 100% bootstrap value and a high decay index (13). The average sequence divergence value (Kimura’s 2-parameter method) betweenHanabusaya and theAdenophora species is 2.58. The value is significantly (about ten times) lower than the ones observed betweenHanabusaya and the species ofCampanula (average of 23.52) and betweenHanabusaya andSymphyandra (24.95). The ITS sequence phylogeny suggests that some morphological characters, such as fused anthers and corolla shape, are homoplastic in the Campanulaceae genera. 相似文献
6.
Phylogenetic studies are often hampered by the independent evolution of characters that may potentially obscure relationships. The adaptive significance of the nectar spur and its evolution within the Mexican lobeliads (Campanulaceae) is considered here. The taxonomic delimitations of Heterotoma from the Mexican species within the genera Lobelia and Calcaratolobelia were tested. Independent molecular data were gathered to determine whether the Mexican spurred lobeliads should be treated as distinct genera. The internal transcribed spacer (ITS) region from 18-26S nuclear rDNA and chloroplast DNA from the 3' trnK intron were sequenced from 14 representative species. Our data suggest that Heterotoma, as originally conceived, is a good evolutionary unit within Lobelia and that the presence of a nectar spur is an important morphological character that can be used in defining phylogenetic position. This study also suggests that morphological changes associated with hummingbird pollination have evolved more than once in the Mexican lobeliads, from small blue-flowered, insect-pollinated relatives. 相似文献
7.
Thomas G. Lammers 《Brittonia》1993,45(1):28-31
Siphocampylus platysiphon (Campanulaceae: Lobelioideae) is described as a new species from northern Peru. It is a member of subsect.Megastomi in sect.Brachysiphon and is most closely related toS. giganteus, a species common to the north in Ecuador and Colombia. 相似文献
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A new Lobelia species is described from Mount Guiting Guiting, an ultramafic mountain on Sibuyan Island in the Philippines. 相似文献
10.
Adenophora erecta S. Lee, J. Lee et S. Kim, is described as a new species from an open north-facing mountain slope on the coast of Sukpo-Dong, Ullungdo Is., Kyungsangbukdo, Korea. This species resemblesA. remotiflora Miq., but is well separated by having the leaves compactly arranged along the upper part of the stem, condensed raceme, distinct veins on the corolla and especially shallow dome-shaped epigynous nectar disc. 相似文献
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G. J. Anderson G. Bernardello P. S. Lopez D. J. Crawford T. F. Stuessy 《Plant Systematics and Evolution》2000,223(1-2):109-123
The reproductive biology ofW. berteroi, W. fernandeziana, and a putative hybrid betweenW. fernandeziana andW. grahamiae, endemic to Robinson Crusoe Island (Juan Fernández archipelago, Chile) was studied. Flowers are hermaphroditic, protandrous, offer nectar, and exhibit secondary pollen presentation involving pollen collecting hairs on the style. These features imply allogamy and biotic pollination. However, male and female phases overlap and no effective pollinators were observed. Experimental data indicate these taxa are self-compatible and facultatively autogamous, a conclusion also suggested by the pollen/ovule ratios. Selfing is accomplished when the stigmatic lobes reflex and touch the style, except forW. berteroi where they do not reflex completely. Autogamy is accomplished in the latter when pollen grains deposited on the inner surface of the corolla throat by the pollen brush are gathered by stigmatic lobes when shaken by wind. The degree of autogamy, and perhaps self-compatibility, seems to be inconstant, as implied by the variable natural seed set (overall range 21–188 seeds per fruit). A mixed mating system — primarily outcrossing/entomophilous, but also autogamous — must have been present in the continental ancestors of these taxa. Autogamy promoting self-fertilization is important now — on an island with scarce pollinators — and in the past — when the first founders arrived. 相似文献
14.
Elmira Khansari Shahin Zarre Kamaleddin Alizadeh Farideh Attar Fatemeh Aghabeigi Yasaman Salmaki 《Flora》2012
Pollen grains of 47 taxa of Campanulaceae including 35 taxa of Campanula that represent its five subgenera and nine sections are investigated. Moreover, five species and three subspecies representing three sections in Asyneuma and one species of each genera Legousia, Michauxia, Zeugandra and Theodorovia were studied by light and scanning electron microscopy. The basic shape of the pollen grains was spheroidal. The apertures vary from tri- to hexa-porate. The sculpturing pattern of exine was rugulate-echinate, rugulate-microechinate or in few species rugulate-microreticulate and microechinate. The most valuable characters for subgeneric classification were the length and density of echini. The length of echini were significantly long (> 2 μm) in C. sclerotricha, Legousia falcata and Michauxia laevigata. Pollen grains show low variation in different species of subgen. Rapunculus, but were variable among different species of some groups, such as sect. Rupestres, probably indicating their non-monophyly despite homogeneity with respect to other morphological characters. Pollen morphology does not support recognition of Asyneuma, Legousia, Michauxia, Symphyandra, Theodorovia, and Zeugandra as separated from Campanula, since none of them exhibit any unique feature. 相似文献
15.
Abstract The Acacia acuminata complex includes three taxa, A. acuminata ssp. acuminata, A. acuminata ssp. burkittii and A. oldfieldii, along with several informal variants of A. acuminata. It is widespread throughout southern Australia with the centre of diversity in south‐west Western Australia. Phylogeographical patterns in the complex were investigated using a nested clade analysis of cpDNA RFLPs from 25 populations in Western Australia. Except for A. oldfieldii that was clearly identified as a distinct entity, haplotypes were not restricted to sub‐specific taxa or variants within A. acuminata. There was significant association between phylogenetic position of many haplotypes and their geographical distribution. The fine‐scale phylogeographical patterns were complex but at deeper levels in the phylogeny there was evidence of divergence between two lineages. The pattern of shared haplotypes between lineages suggests retention of ancestral polymorphism as a result of incomplete lineage sorting. The divergence of these lineages is consistent with fragmentation caused by climatic instability during the Pleistocene. 相似文献
16.
Abstract All life-history stages of the Australian Podonominae (Chironomidae) genus Archaeochlus Brundin are revised, providing evidence for recognition of a separate clade, named here as Austrochlus Cranston. Based on molecular and morphological evidence, the clade contains two additional species: Austrochlus parabrundini Cranston, Edward and Cook sp. n. is described from Western Australia where its granite outcrop seepage habitat and geographical range is almost identical to that of the type species Austrochlus brundini Cranston, Edward and Colless (n. comb); Austrochlus centralaustralis Cranston, Edward and Cook sp. n. is described from ephemeral seepage/flows in the MacDonnell and James Ranges of central Australia. Molecular studies reported here confirm species distinctions, relationships to African taxa, and basal relationships within the Chironomidae. Modelled distributions provide evidence for range restriction by seasonal rainfall patterns. 相似文献
17.
Ando T Kokubun H Watanabe H Tanaka N Yukawa T Hashimoto G Marchesi E Suárez E Basualdo IL 《Annals of botany》2005,96(2):289-297
BACKGROUND AND AIMS: The phylogenetic relationships of Petunia sensu Jussieu (Petunia sensu Wijsman plus Calibrachoa) are unclear. This study aimed to resolve this uncertainty using molecular evidence. METHODS: Phylogenetic trees of 52 taxa of Petunia sensu Jussieu were constructed using restriction fragment length polymorphism (RFLP) of chloroplast DNA digested with 19 restriction enzymes and hybridized with 12 cloned Nicotiana chloroplast DNA fragments as probes. KEY RESULTS: In all, 89 phylogenetically informative RFLPs were detected and one 50 % majority consensus tree was obtained, using the maximum parsimony method, and one distance matrix tree, using the neighbour joining method. Petunia sensu Wijsman and Calibrachoa were monophyletic sister clades in both trees. Calibrachoa parviflora and C. pygmaea, previously thought to differ from the other species in terms of their cross-compatibility, seed morphology, and nuclear DNA content, formed a basal clade that was sister to the remainder of Calibrachoa. Several clades found in the phylogenetic trees corresponded to their distribution ranges, suggesting that recent speciation in the genus Petunia sensu Jussieu occurred independently in several different regions. CONCLUSIONS: The separation of Petunia sensu Wijsman and Calibrachoa was supported by chloroplast DNA analysis. Two groups in the Calibrachoa were also recognized with a high degree of confidence. 相似文献
18.
The intra- and interspecific phylogeny of Fagopyrum (Polygonaceae) species was studied using nucleotide sequence data from two noncoding regions in chloroplast DNA, the trnK (UUU) intron and the trnC (GCA)-rpoB spacer. Thirty-seven accessions of ten species and two unidentified samples in the urophyllum group of Fagopyrum were analyzed. Both of the studied regions showed high variability, including nucleotide substitutions, insertion/deletions, and inversions. Separate parsimony analyses of the two regions generated phylogenies that were largely consistent with each other. A single most parsimonious tree derived from the combined data of the two regions suggested that (1) either F. statice or F. leptopodum was derived from the ancestor more than once, (2) F. gracilipes, a tetraploid species, has recently been derived from diploid ancestor and rapidly spread out to its present distribution areas, and (3) F. pleioramosum, F. macrocarpum, and F. callianthum, three newly discovered species endemic to the upper Min River valley, differentiated from their common ancestral species in the present distribution area. 相似文献
19.
To elucidate the evolutionary history of the genus Capsella, we included the hitherto poorly known species C. orientalis and C. thracica into our studies together with C. grandiflora, C. rubella and C. bursa‐pastoris. We sequenced the ITS and four loci of noncoding cpDNA regions (trnL – F, rps16, trnH –psbA and trnQ –rps16). Sequence data were evaluated with parsimony and Bayesian analyses. Divergence time estimates were carried out with the software package BEAST. We also performed isozyme, cytological, morphological and biogeographic studies. Capsella orientalis (self‐compatible, SC; 2n = 16) forms a clade (eastern lineage) with C. bursa‐pastoris (SC; 2n = 32), which is a sister clade (western lineage) to C. grandiflora (self‐incompatible, SI; 2n = 16) and C. rubella (SC; 2n = 16). Capsella bursa‐pastoris is an autopolyploid species of multiple origin, whereas the Bulgarian endemic C. thracica (SC; 2n = 32) is allopolyploid and emerged from interspecific hybridization between C. bursa‐pastoris and C. grandiflora. The common ancestor of the two lineages was diploid and SI, and its distribution ranged from eastern Europe to central Asia, predominantly confined to steppe‐like habitats. Biogeographic dynamics during the Pleistocene caused geographic and genetic subdivisions within the common ancestor giving rise to the two extant lineages. 相似文献
20.
TAKASHI NAKADA HISAYOSHI NOZAKI MASARU TOMITA 《The Journal of eukaryotic microbiology》2010,57(4):379-382
ABSTRACT. Colonial volvocaleans (Chlorophyceae) are used as a standard model of multicellular evolution. However, the phylogenetic position of the colonial volvocalean family Spondylomoraceae has yet to be resolved. To examine this, the molecular phylogenies of Pyrobotrys stellata and Pyrobotrys squarrosa were analyzed using combined 18S rRNA, RUBISCO large subunit, and P700 chl a‐apoprotein A2 gene sequences. In the phylogenetic trees, Pyrobotrys belonged to the clade Caudivolvoxa and was not closely related to other colonial volvocalean flagellates. The results indicate that colony formation of Spondylomoraceae independently evolved from unicellular volvocaleans. The phylogenetic position of problematic “Pascherina tetras” SAG 159‐1 was also analyzed. 相似文献