| 1. |
- Olsson, Åsa, et al.
(författare)
-
Relationships between Nordic dogroses (Rosa L. sect. Caninae, Rosaceae) assessed by RAPDs and elliptic Fourier analysis of leaflet shape
- 2000
-
Ingår i: Systematic Botany. - 0363-6445. ; 25:3, s. 511-521
-
Tidskriftsartikel (refereegranskat)abstract
- The taxonomy of the dogroses (Rosa sect. Caninae) is notoriously problematic and all the members of the section are characterized by a form of unbalanced meiosis (so-called "canina meiosis"). We used a novel combination of random amplified polymorphic DNA (RAPD) markers and elliptic Fourier analysis of leaflet shape to investigate relationships within and between the seven common dogrose tara in the Nordic countries. A between-individual genetic distance matrix calculated on the basis of the presence/absence of RAPD hands was used in a non-metric multidimensional scaling analysis. Population data from elliptic Fourier analysis of leaflet shape were analyzed with canonical variates analysis. Elliptic Fourier analysis of leaflet shape provided a valuable complement to traditional, often subjectively-assessed, morphological characters and detected subtle patterns of within- and between-taxon differentiation that are generally consistent with the relationships recognized in the current taxonomic treatments of the section. In contrast, RAPDs emphasize the discontinuities between three groups of taxa and suggest that R. canina and the two subspecies of X. dumalis, as well as the taxon-pair A, sherardii and X. villosa subsp. mollis, are more closely related than can be concluded on the basis of morphological characters.
|
|
| 2. |
|
|
| 3. |
- Andriamihajarivo, Tefy H., et al.
(författare)
-
Phyllopentas flava (Rubiaceae), a New Morphologically Heterodistylous and Functionally Dioecious Species from Madagascar
- 2011
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 36:4, s. 1024-1027
-
Tidskriftsartikel (refereegranskat)abstract
- A new species of the Afro-Malagasy genus Phyllopentas Karehed & B. Bremer, Phyllopentas flava Razafim., T. Andriam. et Karehed, is described and illustrated. This plant is restricted to the Itremo region in southeastern Madagascar and is distinct morphologically from the other species of the genus by its pubescent, narrowly ovate to narrowly elliptic leaves, grey-whitish and thickly hairy midribs and secondary veins on the lower surfaces of leaves, and functionally dioecious and heterodistylous flowers. Summaries of distribution, phenology, habitat, and ecology are given and a conservation assessment is also provided.
|
|
| 4. |
- Chazot, Nicolas
(författare)
-
Phylogenomics of the Palm Tribe Lepidocaryeae (Calamoideae: Arecaceae) and Description of a New Species of Mauritiella
- 2021
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 46, s. 863-874
-
Tidskriftsartikel (refereegranskat)abstract
- The palm tribe Lepidocaryeae (Arecaceae) comprises seven genera and 51 currently accepted species that are distributed in lowland tropical forests and savannas across Africa and the Americas. Subtribal relationships within Lepidocaryeae have been a persistent challenge, limiting our understanding of its systematics, morphology, and biogeography. Several aspects make the tribe an ideal system to study plant evolution and diversity: it is well-represented in the fossil record as a prolific pollen producer, its continental diversity contradicts common biodiversity patterns of lower species richness in Africa in comparison to South America, and it contains one of the most abundant Amazonian tree species, Mauritia flexuosa. Here, we investigated the systematics of the tribe by sampling 122 individuals representing 42 species (82% of the tribe), using target sequence capture. We recovered nearly 10,000 single nucleotide polymorphisms from nuclear and plastid DNA across 146 target sequences to separately infer a phylogenomic tree. Our results strongly support inter-generic and inter-specific relationships, where a majority of nodes were resolved with over 90% bootstrap support. We also identify strong phylogenetic support for the recognition of a new species from central and south Amazonia, Mauritiella disticha. The distichous phyllotaxy is diagnostic of the species within the genus. Rare and currently only known from the middle-lower Madeira River basin in the state of Amazonas, Brazil, M. disticha is restricted to open vegetation and forest edges growing in white sand habitats with saturated or well-drained soils. Our preliminary red list assessment suggests its threatened status to be vulnerable (VU). We use our phylogenomic inference to define and contextualize systematic relationships in the tribe, and present a formal species description.
|
|
| 5. |
- Daniel, Thomas F., et al.
(författare)
-
The "Tetramerium Lineage" (Acanthaceae : Acanthoideae : Justicieae) : Delimitation and intra-lineage relationships based on cp and nrITS sequence data
- 2008
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 33:2, s. 416-436
-
Tidskriftsartikel (refereegranskat)abstract
- We used DNA sequence data from five genic regions (nrITS; chloroplast trnL-F, trnT-L, rps16, trnS-G) to study phylogenetic relationships of the Tetramerium lineage (Acanthaceae: Justicieae). From a sample of 70 species (representing 25 genera) previously affiliated with the Tetramerium lineage, 68 are included therein. Our analyses excluded Papuasian Calycacanthus and Neotropical Streblacanthus monospermus from the Tetramerium lineage; however, two species described in Justicia (J. gonzalezii and J. medranoi) and a Malagasy species of uncertain generic affinities are nested within the lineage. A monophyletic Tetramerium lineage consists of 23 currently recognized genera with at least 168 species, more than 70% of which occur in the New World. Old World Chlamydocardia and Clinacanthus are serially sister to all other members of the lineage. Other Old World taxa consist of: Ecbolium clade (all sampled species of Ecbolium plus Malagasy Populina richardii), Megalochlamys clade (Megalochlamys, Trichaulax and the unidentified Malagasy species), and two isolated taxa (Angkalanthus and Chorisochora). All analyses strongly support monophyly of the New World Tetramerium lineage. The basal clades of New World plants, all with nototribic flowers, are: 1) the taxonomically heterogeneous but palynologically consistent Mirandea clade, and 2) the Pachystachys clade + the South American Anisacanthus clade. The second is sister to all other NW plants, referred to here as the core Tetramerium lineage. We recognize five clades within the core Tetramerium lineage related as follows: (Henrya clade (Carlowrightia parviflora clade (North American Anisacanthus clade (core Carlowrightia clade + Tetramerium)))). Macromorphological synapomorphies are unknown for the Tetramerium lineage and for many of its constituent clades. However, we propose sternotribic flowers as synapomorphic for the core Tetramerium lineage, and flowers with the lower-central lobe of the corolla modified into a keel as a synapomorphy for a lineage consisting of Tetramerium and the core Carlowrightia clade. Palynological characters provide putative synapomorphies for some clades (e.g. Ecbolium clade, Mirandea clade) and autapomorphies for several species (e.g. Mexacanthus mcvaughii, Trichalux mwasumbii). An Old World origin is postulated for the Tetramerium lineage, and we posit a single dispersal event to America and subsequent extensive radiation there, especially in arid zones of Mexico and adjacent regions. Taxonomic implications of our results are extensive. Notably, many traditionally recognized genera (e.g. Anisacanthus, Carlowrightia, Mirandea) are not monophyletic and emphasis on floral form often has been phylogenetically misleading; for example, floral adaptations to pollination by hummingbirds have evolved at least eight times in the New World Tetramerium lineage.
|
|
| 6. |
- Ekenäs, Catarina, et al.
(författare)
-
A molecular phylogenetic study of Arnica (Asteraceae) : Low chloroplast DNA variation and problematic subgeneric classification
- 2007
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 32:4, s. 917-928
-
Tidskriftsartikel (refereegranskat)abstract
- DNA sequences from five chloroplast DNA regions (the rpl16 and rps16 introns and the psbA-trnH, ycf4-cemA, and trnT-L spacers), and the nuclear ribosomal internal and external transcribed spacer (ITS and ETS) regions, were analyzed using maximum parsimony and Bayesian methods to explore the putatively complicated history of the mainly North American genus Arnica. The chloroplast regions were found to contain minimal variation in Arnica. Of 3710 nucleotides, only 119 were variable and 45 informative. However, combined with the ribosomal DNA data, the analysis yielded a number of well-supported clades. Strong support for the monophyly of Arnica was found in both the separate and combined analyses but none of the five currently recognized subgenera was resolved as monophyletic in any of the analyses. Arnica (Whitneya) dealbata and A. mallotopus (Mallotopus japonicus), two species that were previously placed outside Arnica, were confidently confirmed as members of the genus. The analyses revealed that A. nevadensis (subg. Austromontana) is most closely related to A. dealbata and that A. mallotopus forms a strongly supported clade with A. unalaschcensis (subg. Andropurpurea). Earlier biogeographical hypotheses that suggested an arctic origin and southward spread of the genus are not supported by our analyses. Hybridization, homoplasy, and rapid evolution are possible explanations for conflicts between the chloroplast and nuclear ribosomal data sets and for low support of the deeper nodes.
|
|
| 7. |
- Ferm, Julia, et al.
(författare)
-
A Revised Subgeneric Classification of the Neotropical Genus Zapoteca (Caesalpinioideae; Fabaceae)
- 2022
-
Ingår i: Systematic Botany. - : American Society of Plant Taxonomists. - 0363-6445 .- 1548-2324. ; 47:1, s. 208-214
-
Tidskriftsartikel (refereegranskat)abstract
- The subgeneric classification of the neotropical legume genus Zapoteca is revised based on an analysis of the nuclear ETS and ITS, and the plastid trnL-trnF DNA regions. Zapoteca subgenus Ravenia is included in Z. subgenus Zapoteca, Z. quichoi is transferred from Z. subgenus Amazonica to Z. subgenus Zapoteca, Z. sousae is included in Z. subgenus Zapoteca, and the new subgenus Zapoteca subgenus Subamazonica is described to accommodate the species Z. filipes and Z. scutellifera. A key to the subgenera is presented.
|
|
| 8. |
- Fritsch, Peter W., et al.
(författare)
-
Taxonomic Implications of Morphological Variation in Cercis canadensis (Fabaceae) from Mexico and Adjacent Parts of Texas
- 2009
-
Ingår i: Systematic Botany. - : American Society of Plant Taxonomists. - 0363-6445 .- 1548-2324. ; 34:3, s. 510-520
-
Tidskriftsartikel (refereegranskat)abstract
- Taxonomic treatments recognize three varieties of Cercis canadensis: with variety canadensis, widespread throughout the eastern United States, and varieties texensis and mexicana, found east and west of the Pecos River in Texas, respectively. The distribution of Cercis continues southward into northeastern Mexico, but complex variation in leaf shape has confounded straightforward application of varietal names to the Mexican plants. To clarify the taxonomy of Cercis in Mexico, we conducted a morphometric analysis with 281 herbarium specimens, including a representative set of samples from Texas. Correlation and principal component analysis of 12 characters recovered two groups that correspond to the presence versus absence of branchlet pubescence. These groups are geographically distinct at the northern and southern extremes of the focus area but exhibit a large central region of overlap. No other discontinuities in character states were discovered to corroborate this division. Leaf shape varies continuously from ovate-acuminate at the northern and southern extremes to subreniform in the central region, suggesting clinal adaptation to the mesic versus xeric environments in which the plants occur. Based on our data, we apply the varietal epithets mexicana and, provisionally, texensis to Mexican C. canadensis with pubescent and glabrous branchlets, respectively, the latter based on geographic proximity to plants in Texas in the absence of definitive evidence on the phenotypic distinction between varieties canadensis and texensis.
|
|
| 9. |
- Havran, J. Christopher, et al.
(författare)
-
Taxonomic Reevaluation of Endemic Hawaiian Planchonella (Sapotaceae)
- 2021
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 46, s. 875-888
-
Tidskriftsartikel (refereegranskat)abstract
- Planchonella (Sapotaceae) in Hawaii has a complicated taxonomic history that has resulted in considerable confusion among bota- nists and conservation practitioners. Up to seven different species and several varieties have been described in Hawaii, with the most recent taxonomic evaluation recognizing one species, P. sandwicensis. We have conducted a phylogenetic study of Hawaiian Planchonella using molec- ular (ETS, ITS, and RPB2) and morphological data to infer whether one or several species can be distinguished. In line with earlier research based on molecular data, we find that Planchonella in Hawaii is comprised of two well-supported clades distinguished by fruit color: yellow or purple. The purple-fruited clade contains individuals with flat leaf blades, long pedicels, and greenish corollas, a species corresponding to P. sandwicensis, distributed on all Hawaiian Islands except the island of Hawaii. The yellow-fruited clade possesses leaves that are frequently longitudinally rolled, wavy or distally deflexed, short pedicels, and yellow or cream (rarely greenish) corollas, a species corresponding to P. spathulata that is distributed on all Hawaiian Islands but is believed rare in Kauai. Both species can set fruit with aborted ovules, resulting in small fruits that look dissimilar to well-developed fruit. The species can occur in sympatry, where P. sandwicensis seems to be better adapted to slightly wetter forests and higher altitudes, whereas P. spathulata usually occurs at lower elevations in mesic to dry forests. Both species exhibit large morphological variation and overlap, resulting in many previous collections with inadequate label information, which has impeded correct taxonomic determinations. We refrain from recognizing infraspecific taxa because there is no morphological coherence, no molecular support, and it is unhelpful for species conservation. Five lectotypes are here designated. Both species are assessed for conservation status according to IUCN guidelines and are tentatively proposed as species of Least Concern.
|
|
| 10. |
- Havran, J. C., et al.
(författare)
-
Taxonomic Reevaluation of Endemic Hawaiian Planchonella (Sapotaceae)
- 2021
-
Ingår i: Systematic Botany. - : American Society of Plant Taxonomists. - 0363-6445. ; 46:3, s. 875-888
-
Tidskriftsartikel (refereegranskat)abstract
- Planchonella (Sapotaceae) in Hawaii has a complicated taxonomic history that has resulted in considerable confusion among botanists and conservation practitioners. Up to seven different species and several varieties have been described in Hawaii, with the most recent taxonomic evaluation recognizing one species, P. sandwicensis. We have conducted a phylogenetic study of Hawaiian Planchonella using molecular (ETS, ITS, and RPB2) and morphological data to infer whether one or several species can be distinguished. In line with earlier research based on molecular data, we find that Planchonella in Hawaii is comprised of two well-supported clades distinguished by fruit color: yellow or purple. The purple-fruited clade contains individuals with flat leaf blades, long pedicels, and greenish corollas, a species corresponding to P. sandwicensis, distributed on all Hawaiian Islands except the island of Hawaii. The yellow-fruited clade possesses leaves that are frequently longitudinally rolled, wavy or distally deflexed, short pedicels, and yellow or cream (rarely greenish) corollas, a species corresponding to P. spathulata that is distributed on all Hawaiian Islands but is believed rare in Kauai. Both species can set fruit with aborted ovules, resulting in small fruits that look dissimilar to well-developed fruit. The species can occur in sympatry, where P. sandwicensis seems to be better adapted to slightly wetter forests and higher altitudes, whereas P. spathulata usually occurs at lower elevations in mesic to dry forests. Both species exhibit large morphological variation and overlap, resulting in many previous collections with inadequate label information, which has impeded correct taxonomic determinations. We refrain from recognizing infraspecific taxa because there is no morphological coherence, no molecular support, and it is unhelpful for species conservation. Five lectotypes are here designated. Both species are assessed for conservation status according to IUCN guidelines and are tentatively proposed as species of Least Concern.
|
|
| 11. |
- Kårehed, Jesper, et al.
(författare)
-
Evolution of the Australasian families Alseuosmiaceae, Argophyllaceae, and Phellinaceae
- 1999
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 24:4, s. 660-682
-
Tidskriftsartikel (refereegranskat)abstract
- Based on results from cladistic analyses of morphology and DNA sequences (the two chloroplast genes rbcL and ndhF), the three Australasian families Alseuosmiaceae, Argophyllaceae, and Phellinaceae are each monophyletic, belong within Asterales, and together form a monophyletic group. Two new rbcL sequences and thirteen new ndhF sequences were obtained. Congruence tests did not reveal any significant incongruence between the two molecular data sets or between the molecular and morphological data. The character evolution of the Alseuosmiaceae-Argophyllaceae-Phellinaceae group is discussed. The Australasian ancestor of this group was probably a woody plant with simple, alternate, serrate leaves and regular, choripetalous, epigynous flowers borne in panicles. All tree families should be retained in line with the "principle of ease of identification."
|
|
| 12. |
|
|
| 13. |
|
|
| 14. |
- Löfstrand, Stefan D., et al.
(författare)
-
Phylogeny and Generic Delimitations in the Sister Tribes Hymenodictyeae and Naucleeae (Rubiaceae)
- 2014
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 39:1, s. 304-315
-
Tidskriftsartikel (refereegranskat)abstract
- The Hymenodicteae-Naudeeae clade is a predominantly Paleotropical group with 220 species in 28 genera. The phylogertetic relationships and generic limits within Naucleeae have previously been assessed using combined molecular-morphological data, however the status of some genera remains questionable. The evolutionary relationships within Hymenodictyeae have never been investigated before. We performed phylogenetic analyses of the Hymenodictyeae-Naucleeae clade using nuclear [nrETS; nrITS] and chloroplast [ndhF; rbcL; rps16; trnT-F] data and a large sampling of both tribes. Our study supports the monophyly of the tribes, all subtribes of Naucleeae (Adininae, Breoniinae, Cephalanthinae, Corynantheinae, Mitragyninae, Naucleinae, and Uncariinae), and the Hymenodictyeae genera Hymenodictyon and Paracorynanthe. In Naucleeae, the monotypic genera Adinauclea, Metadina, and Pertusadina are nested within Adina, Mitragyna within Fleroya, Ludekia, Myrmeconauclea, and Ochreinauclea within Neonauclea, and Burttdavya and Sarcocephalus within Nauclea. Corynanthe and Pausinystalia are mutually paraphyletic. We provisionally maintain the current generic status of Neonauclea and its allied genera, pending further study. In sum, we recognize 17 genera in Naucleeae: Adina s. l., Breonadia, Breonia, Cephalanthus, Corynanthe s. l., Diyaminauclea, Gyrostipula, Janotia, Khasiaclunea, Ludekia, Mitragyna s. l., Myrmeconauclea, Nauclea s. l., Neolamarckia, Neonauclea, Ochreinauclea, and Uncaria. Five new combinations were made: Adina euryncha, Adina malaccensis, Corynanthe lane-poolei subsp. iturense, Corynanthe talbotii, and Nauclea nyasica.
|
|
| 15. |
|
|
| 16. |
- Manns, Ulrika, 1965-, et al.
(författare)
-
Character Evolution in Anagallis (Myrsinaceae) Inferred from Morphological and Molecular Data
- 2007
-
Ingår i: Systematic Botany. - : American Society of Plant Taxonomists. - 0363-6445 .- 1548-2324. ; 32:1, s. 166-179
-
Tidskriftsartikel (refereegranskat)abstract
- Morphological and molecular data were analyzed using parsimony to trace character evolution within Anagallis s.l., including Anagallis, Asterolinon, Pelletiera, Lysimachia nemorum, and L. serpyllifolia, which are distributed among two sister clades. The first clade, comprising Anagallis arvensis, A. foemina, A. monelli, Asterolinon, Pelletiera, Lysimachia nemorum, and L. serpyllifolia is supported by synapomorphies such as an annual, repeatedly branching habit, sessile leaves, flowers in almost all leaf axils, and membranous slightly dentate calyx margins, of which all but the last are homoplasious within Anagallis s.l.. The second clade, comprising Anagallis species only, is supported by a large number of synapomorphies, of which the majority are floral features. Placement of ten taxa, for which no DNA was available, is proposed based on morphological characters evaluated in the light of the result of the phylogenetic analysis of sequenced taxa.
|
|
| 17. |
- Monge, M., et al.
(författare)
-
Nomenclatural novelties in Tessaria (Asteraceae, Inuleae): a new species from the Andes and uncovering the identity of T. boliviensis.
- 2018
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 43:2, s. 591-594
-
Tidskriftsartikel (refereegranskat)abstract
- During the study of Brazilian genera of the Inuleae-Plucheinae (Asteraceae), we have encountered a specimen representing an undescribed species, here described as Tessaria andina. The new species is characterized by having puberulous, tomentose, lanate, or glabrescent indumentum on its branches, a tomentose abaxial leaf surface, leaves with an apically serrate margin, corymbiform inflorescences, a cream to yellowish involucre, erect inner involucral bracts, and the corolla of male flowers with short-stalked glands and trichomes. So far, only one collection of this new species has been made, and that was more than forty years ago. The new species is described, illustrated, and its affinities are discussed. Furthermore, during this investigation we found out that the name Tessaria boliviensis is a nomen nudum, applied to material here shown tobelongto Tessaria fastigiata. An identification key to the species of Tessaria is also presented.
|
|
| 18. |
- Morrison, David A.
(författare)
-
Is Sequence Alignment an Art or a Science?
- 2015
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 40:1, s. 14-26
-
Tidskriftsartikel (refereegranskat)abstract
- Aligning multiple nucleotide sequences is a prerequisite for many if not most comparative sequence analyses in evolutionary biology. These alignments are often recognized as representing the homology relations of the aligned nucleotides, but this is a necessary requirement only for phylogenetic analyses. Unfortunately, existing computer programs for sequence alignment are not based explicitly on detecting the homology of nucleotides, and so there is a notable gap in the existing bioinformatics repertoire. If homology is the goal, then current alignment procedures may be more art than science. To resolve this issue, I present a simple conceptual scheme relating the traditional criteria for homology to the features of nucleotide sequences. These relations can then be used as optimization criteria for nucleotide sequence alignments. I point out the way in which current computer programs for multiple sequence alignment relate to these criteria, noting that each of them usually implements only one criterion. This explains the apparent dissatisfaction with computerized sequence alignment in phylogenetics, as any program that truly tried to produce alignments based on homology would need to simultaneously optimize all of the criteria.
|
|
| 19. |
|
|
| 20. |
|
|
| 21. |
- Owusu, Sandra A., et al.
(författare)
-
Taxonomic Relationships and Gene Flow in Four North American Quercus Species (Quercus section Lobatae)
- 2015
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 40:2, s. 510-521
-
Tidskriftsartikel (refereegranskat)abstract
- Taxonomic relationships between North American red oak species (Quercus section Lobatae) are not well resolved using genetic and morphological markers. Phenotypic plasticity, recent species divergence, and hybridization may all contribute to the unclear species boundaries in red oaks. We applied twenty-eight genomic and gene-basedmicrosatellites, including outlier loci with potential roles in reproductive isolation and adaptive divergence between species, to natural populations of four monophyletic interfertile oak species: Quercus ellipsoidalis, Q. coccinea, Q. rubra, and Q. velutina. To better resolve the taxonomic relationships in this difficult clade, we assigned individual samples to species, identified hybrids and introgressive forms, and reconstructed phylogenetic relationships among the four species after exclusion of genetically intermediate individuals. Genetic assignment analyses identified four distinct species clusters, with Q. rubra most differentiated from the three other species. However, especially between Q. ellipsoidalis and Q. velutina, a comparatively large number of misclassified individuals (7.14%), hybrids (7.14%), and introgressive forms (18.83%) were detected. After the exclusion of genetically intermediate individuals, Q. ellipsoidalis grouped as sister species to the largely parapatric Q. coccinea with high bootstrap support (91%). Genetically intermediate forms in a mixed species stand were located proximate to both potential parental species, which supports recent hybridization of Q. velutina with both Q. ellipsoidalis and Q. rubra. Analyses of genome-wide patterns of interspecific differentiation can provide a better understanding of speciation processes and taxonomic relationships in this taxonomically difficult group of red oak species.
|
|
| 22. |
|
|
| 23. |
- Rautenberg, Anja, et al.
(författare)
-
Phylogenetic relationships of Silene multinervia and Silene section Conoimorpha (Caryophyllaceae)
- 2012
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 37:1, s. 226-237
-
Tidskriftsartikel (refereegranskat)abstract
- The Californian Silene multinervia (Caryophyllaceae) and Eurasian members of section Conoimorpha in subgenus Behenantha are the only Silene species that have calyces with 15 or more prominent parallel, unbranched veins. We show that S. multinervia, which has been considered a recent introduction of the Asian S. coniflora (section Conoimorpha) to North America, is clearly not synonymous with the latter species based on morphological or molecular data. We present a chromosome count of S. multinervia (2n = 24), which is different from the base number x = 10, a putative synapomorphy for section Conoimorpha. Gene trees based on sequences from three different genomes fail to group S. multinervia with the European section Conoimorpha species. The S. multinervia sequences form a monophyletic group placed in an unresolved position within subgenus Behenantha.
|
|
| 24. |
|
|
| 25. |
- Schwartz, Thomas, et al.
(författare)
-
The origin of oranges: a multi-locus phylogeny of Rutaceae subfamily Aurantioideae
- 2015
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 40:4
-
Tidskriftsartikel (refereegranskat)abstract
- The phylogeny of Rutaceae subfamily Aurantioideae has previously been estimated only using plastid and repetitive nuclear sequences. We added sequences of two low copy nuclear loci to allow further diagnosis of phenomena that may mislead phylogenetic inference. After testing for patterns expected under recombination, positive selection, and hybridization, we excluded data sets or sequences accordingly and then inferred the species tree using the multispecies coalescent. We then reconstructed the ancestral area using parsimony and the dispersal-extinction-cladogenesis model to test the hypothesis that Citrus s. l. may have originated in Australasia and migrated or rafted to Eastern Asia. The ancestral area of Citrus s. l. inferred under either method and several models was west of Wallace’s line. Therefore, Citrus s. l. did not appear to have rafted west on what became the Halmahera Islands (Indonesia). Our findings are also consistent with previously reported ages for the origin of this group that may be too young to have allowed this rafting. The species tree is well resolved and largely consistent with previous molecular phylogenies, especially those using chloroplast sequences.
|
|
| 26. |
- Swenson, U, et al.
(författare)
-
Pacific biogeography of the asteraceae genus Abrotanella (Senecioneae, Blennospermatinae)
- 1997
-
Ingår i: SYSTEMATIC BOTANY. - : AMER SOC PLANT TAXONOMISTS. - 0363-6445. ; 22:3, s. 493-508
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Historical biogeography of the trans-Pacific Asteraceae genus Abrotanella (Senecioneae, Blennospermatinae) was analyzed with cladistic methods. The genus comprises 19 alpine species and is restricted to six areas of endemism, South America, Australia-New
|
|
| 27. |
- Terra-Araujo, Mário H., et al.
(författare)
-
A taxonomic update of Neotropical Pradosia (Sapotaceae, Chrysophylloideae)
- 2016
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 41, s. 634-650
-
Tidskriftsartikel (refereegranskat)abstract
- We provide a systematic update of Pradosia (Sapotaceae, Chrysophylloideae), including overall morphology, a key to all species, comprehensive morphological descriptions, geographic distributions, and important characteristics for each species. Phyloge- netic analyses based on molecular data demonstrated that the genus is monophyletic and includes three main clades. Twenty-three species of Pradosia are accepted, which are mostly distributed in lowland rainforests on either white-sand or clayish soils in tropical South America. A rotate corolla with a short tube, lack of staminodes, a drupaceous fruit with plano-convex cotyledons, an exserted radicle below the cotyledons, and the absence of endosperm are diagnostic for the genus. Two names are reduced into synonymy, viz. Pradosia atroviolacea Ducke, syn. of P. grisebachii (Pierre) T. D. Penn., and Pradosia verrucosa Ducke, syn. of P. glaziovii (Pierre) T. D. Penn. The affinity of P. argentea (Kunth) T. D. Penn., a species known only from the type collection, remains uncertain and for now excluded from the genus.
|
|
| 28. |
|
|
| 29. |
- Thulin, Mats, 1948-, et al.
(författare)
-
Phylogeny and Systematics of Kewa (Kewaceae)
- 2018
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 43:3, s. 689-700
-
Tidskriftsartikel (refereegranskat)abstract
- The genus Kewa in the monogeneric family Kewaceae (Caryophyllales) is revised. Six species are recognized, K. acida on St. Helena, K. angrae-pequenae in Namibia and South Africa, K. arenicola (incl. K. trachysperma) in South Africa, K. bowkeriana (incl. K. suffruticosa) widespread in eastern and southern Africa and in Madagascar, K. caespitosa in Angola and Namibia, and K. salsoloides in Namibia, Botswana, and South Africa. Kewa is morphologically distinctive, notably by its simple perianth where the two outer perianth-segments are more or less sepaloid and the three inner ones more or less petaloid, and by its indumentum of short glandular hairs, often with prominent, persistent, wart-like bases. All species have an acid taste, apparently due to the presence of oxalic acid. All names are typified, including one lectotype designated here. An identification key and distribution maps for all species are provided. The phylogeny of Kewa is reconstructed based on plastid trnK-matK and rbcL and nuclear ITS sequences. Kewa is strongly supported and the included species have strong to no support, whereas the relationships between the species are mostly unsupported. The phylogeny is dated and the estimated age of the Kewa stem clade is (37.5-)45.0(-57.0) million years and of the crown lade (3.0-)3.9(-7.4) million years. The age of the crown lade would also be the estimated date when K. acida on the approximately 14 million years old St. Helena diverged from its potential sister group on the African continent, and would coincide with the earliest possible date for the introduction of the ancestor of K. acida to St. Helena.
|
|
| 30. |
- Thulin, Mats, 1948-, et al.
(författare)
-
Resurrection of the Genus Rorida (Cleomaceae), a Distinctive Old World Segregate of Cleome
- 2017
-
Ingår i: Systematic Botany. - : AMER SOC PLANT TAXONOMISTS. - 0363-6445 .- 1548-2324. ; 42:3, s. 569-577
-
Tidskriftsartikel (refereegranskat)abstract
- The genus Rorida J.F. Gmel. is resurrected for Cleome L. sect. Thylacophora Franch. within the non-monophyletic Cleome. Rorida is strongly supported as monophyletic by molecular data and is also morphologically very distinctive, with simple leaves, four stamens, and triangular, very shortly clawed, dimorphic petals, appendaged at the base. Twelve species are recognized in desert and semidesert regions from northeastern Africa through the Arabian Peninsula to Afghanistan, Tajikistan, and Pakistan. Rorida cornus-africani is described as new from Somalia and new combinations are made for the other eleven species. All names are typified, including 10 lectotypes designated here. An identification key and distribution maps for all species are provided.
|
|
| 31. |
- Torres Jimenez, Maria Fernanda, et al.
(författare)
-
Phylogenomics of the Palm Tribe Lepidocaryeae (Calamoideae: Arecaceae) and Description of a New Species of Mauritiella
- 2021
-
Ingår i: Systematic Botany. - : American Society of Plant Taxonomists. - 0363-6445. ; 46:3, s. 863-874
-
Tidskriftsartikel (refereegranskat)abstract
- The palm tribe Lepidocaryeae (Arecaceae) comprises seven genera and 51 currently accepted species that are distributed in lowland tropical forests and savannas across Africa and the Americas. Subtribal relationships within Lepidocaryeae have been a persistent challenge, limiting our understanding of its systematics, morphology, and biogeography. Several aspects make the tribe an ideal system to study plant evolution and diversity: it is well-represented in the fossil record as a prolific pollen producer, its continental diversity contradicts common biodiversity patterns of lower species richness in Africa in comparison to South America, and it contains one of the most abundant Amazonian tree species, Mauritia flexuosa. Here, we investigated the systematics of the tribe by sampling 122 individuals representing 42 species (82% of the tribe), using target sequence capture. We recovered nearly 10,000 single nucleotide polymorphisms from nuclear and plastid DNA across 146 target sequences to separately infer a phylogenomic tree. Our results strongly support inter-generic and inter-specific relationships, where a majority of nodes were resolved with over 90% bootstrap support. We also identify strong phylogenetic support for the recognition of a new species from central and south Amazonia, Mauritiella disticha. The distichous phyllotaxy is diagnostic of the species within the genus. Rare and currently only known from the middle-lower Madeira River basin in the state of Amazonas, Brazil, M. disticha is restricted to open vegetation and forest edges growing in white sand habitats with saturated or well-drained soils. Our preliminary red list assessment suggests its threatened status to be vulnerable (VU). We use our phylogenomic inference to define and contextualize systematic relationships in the tribe, and present a formal species description.
|
|
| 32. |
- Xue, Tian-Tian, et al.
(författare)
-
Ignored Biodiversity in Acid Soil Islands in Karst Areas, South China : Impatiens longlinensis (Balsaminaceae), a New Critically Endangered Species
- 2020
-
Ingår i: Systematic Botany. - 0363-6445 .- 1548-2324. ; 45:4, s. 891-899
-
Tidskriftsartikel (refereegranskat)abstract
- The karst area in South China is notable for its fragile vegetation and unique flora with many narrow endemic species, and is one of the most threatened biodiversity hotspots in the world. However, the biodiversity of acid soil areas scattered in the karst area have previously been underestimated. With a recent increase of new discoveries of plants and animals, the conservation of biodiversity in these acid soil areas has become urgent. This study deals with a new species, Impatiens longlinensis . The new species is similar to I. yui and I. lasiophyton in having pubescence, two lateral sepals, funnelform lower sepal, and linear capsule. But it can be distinguished by having orbicular to obovate dorsal sepals and oblong to elliptic lower and upper lobes of lateral united petals. Moreover, molecular data and micro-morphological evidence also support that the species is new to science. The new species is only known from a valley near the summit of Mt. Jinzhongshan within an area of less than 5 km2. Based on the Red List categories and criteria developed by the International Union for Conservation of Nature, and the threat posed by exploitation for tourism development, we categorize it as Critically Endangered (CR).
|
|
