| 1. |
- Ferm, Julia, et al.
(författare)
-
Phylogeny of the Neotropical legume genera Zygia and Marmaroxylon and close relatives
- 2019
-
Ingår i: Taxon. - : International Association for Plant Taxonomy. - 0040-0262 .- 1996-8175. ; 68:4, s. 661-672
-
Tidskriftsartikel (refereegranskat)abstract
- The Neotropical legume genera Zygia and Marmaroxylon have traditionally been considered closely related and are sometimes treated as congeners. They have been referred to the mimosoid tribe Ingeae based on their possession of flowers with basally fused stamen filaments. However, their systematic status and position have not been analysed in a phylogenetic context. This study provides the first molecular phylogeny of Zygia and Marmaroxylon and closely related mimosoid legume genera, particularly from the tribe Ingeae. DNA sequence data were derived from the nuclear external transcribed spacer (ETS) and the internal transcribed spacer (ITS), and from the chloroplast psbA-trnH and trnL-trnF regions, and were analysed using Bayesian inference. In all, 29 species of Zygia and 7 species of Marmaroxylon were included in the study along with representative species from the closely related genera Abarema, Acacia s.str., Archidendropsis, Calliandra, Chloroleucon, Cojoba, Faidherbia, Havardia, Hydrochorea, Inga, Leucochloron, Macrosamanea, Pithecellobium, Pseudosamanea, Samanea, Senegalia, Vachellia and Zapoteca. The results show that neither Zygia nor Marmaroxylon are monophyletic as presently circumscribed. Furthermore, these two genera are not monophyletic together. None of the nine presently recognized sections of Zygia that contain more than one species are shown to be monophyletic. Two of the monospecific sections of Zygia, sect. Ingopsis (Z. inundata) and sect. Pseudocojoba (Z. sabatieri), were found in a clade together with species of Inga. Marmaroxylon ocumarense and M. magdalenae, previously treated as synonyms (as Zygia), are not conspecific, and are found in a clade with Macrosamanea and in a clade with species of Abarema and Hydrochorea, respectively. Our results also show the Inga alliance to be non-monophyletic. In correspondence with the results presented, all species referred to Marmaroxylon, except for M. ocumarense and M. magdalenae, are here included in Zygia, and Z. inundata is treated in Inga, in which genus it was first described.
|
|
| 2. |
- Geiger, Jennifer M.O., et al.
(författare)
-
Molecular phylogenetic relationships of Cibotium and origin of the Hawaiian endemics
- 2013
-
Ingår i: American Fern Journal. - : American Fern Society. - 0002-8444 .- 1938-422X. ; 103:3, s. 141-152
-
Tidskriftsartikel (refereegranskat)abstract
- The tree fern genus Cibotium comprises nine species distributed in tropical regions of Asia, Mesoamerica, and the Hawaiian Islands. The four Hawaiian species are endemic to the Hawaiian Islands. The goals of this paper were to determine the relationships among the Cibotium species, determine whether the Hawaiian species are monophyletic, and infer the dispersal pathway likely responsible for delivering an ancestral Cibotium species to the Hawaiian Islands. Molecular phylogenetic analyses based on four coding and five non-coding plastid DNA sequences supported Hawaiian Cibotium as monophyletic, suggesting a single colonization of the Hawaiian Islands. Hawaiian Cibotium are most closely related to species in Mesoamerica. If the ancestor of Hawaiian Cibotium dispersed to the Hawaiian Islands via wind dispersed spores, our analyses suggest the trade winds or storms delivered spores from Mesoamerica or the Hawaiian Islands were colonized first by a species from Asia, followed by subsequent dispersal to Mesoamerica from Hawai'i. Our analyses do not allow us to favor one hypothesis over the other.
|
|
| 3. |
- Korall, Petra, 1968-, et al.
(författare)
-
A molecular phylogeny of scaly tree ferns (Cyatheaceae)
- 2007
-
Ingår i: American Journal of Botany. - : Wiley. - 0002-9122 .- 1537-2197. ; 94:5, s. 873-886
-
Tidskriftsartikel (refereegranskat)abstract
- Tree ferns recently were identified as the closest sister group to the hyperdiverse clade of ferns, the polypods. Although most of the 600 species of tree ferns are arborescent, the group encompasses a wide range of morphological variability, from diminutive members to the giant scaly tree ferns, Cyatheaceae. This well-known family comprises most of the tree fern diversity (similar to 500 species) and is widespread in tropical, subtropical, and south temperate regions of the world. Here we investigate the phylogenetic relationships of scaly tree ferns based on DNA sequence data from five plastid regions (rbcL, rbcL-accD IGS, rbcL-atpB IGS, trnG-trnR, and trnL-trnF). A basal dichotomy resolves Sphaeropteris as sister to all other taxa and scale features support these two clades: Sphaeropteris has conform scales, whereas all other taxa have marginate scales. The marginate-scaled clade consists of a basal trichotomy, with the three groups here termed (1) Cyathea (including Cnemidaria, Hymenophyllopsis, Trichipteris), (2) Alsophila sensu stricto, and (3) Gymnosphaera (previously recognized as a section within Alsophila) + A. capensis. Scaly tree ferns display a wide range of indusial structures, and although indusium shape is homoplastic it does contain useful phylogenetic information that supports some of the larger clades recognised.
|
|
| 4. |
- Korall, Petra, 1968-, et al.
(författare)
-
Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal
- 2014
-
Ingår i: Journal of Biogeography. - : Wiley-Blackwell. - 0305-0270 .- 1365-2699. ; 41:2, s. 402-413
-
Tidskriftsartikel (refereegranskat)abstract
- AimScaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of Gondwana.LocationTropics, subtropics and south-temperate areas of the world.MethodsThe historical biogeography of Cyatheaceae was analysed in a maximum likelihood framework using Lagrange. The 78 ingroup taxa are representative of the geographical distribution of the entire family. The phylogenies that served as a basis for the analyses were obtained by Bayesian inference analyses of mainly previously published DNA sequence data using MrBayes. Lineage divergence dates were estimated in a Bayesian Markov chain Monte Carlo framework using beast.ResultsCyatheaceae originated in the Late Jurassic in either South America or Australasia. Following a range expansion, the ancestral distribution of the marginate-scaled clade included both these areas, whereas Sphaeropteris is reconstructed as having its origin only in Australasia. Within the marginate-scaled clade, reconstructions of early divergences are hampered by the unresolved relationships among the Alsophila, Cyathea and Gymnosphaera lineages. Nevertheless, it is clear that the occurrence of the Cyathea and Sphaeropteris lineages in South America may be related to vicariance, whereas transoceanic dispersal needs to be inferred for the range shifts seen in Alsophila and Gymnosphaera.Main conclusionsThe evolutionary history of Cyatheaceae involves both Gondwanan vicariance scenarios as well as long-distance dispersal events. The number of transoceanic dispersals reconstructed for the family is rather few when compared with other fern lineages. We suggest that a causal relationship between reproductive mode (outcrossing) and dispersal limitations is the most plausible explanation for the pattern observed.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Korall, Petra, 1968-, et al.
(författare)
-
PHYLOGENETIC RELATIONSHIPS IN SELAGINELLACEAE BASED ON RBCL SEQUENCES
- 2002
-
Ingår i: American Journal of Botany. - 0002-9122 .- 1537-2197. ; 89:3, s. 506-517
-
Tidskriftsartikel (refereegranskat)abstract
- A phylogenetic framework is developed for the clubmoss family Selaginellaceae based on maximum parsimony analyses of molecular data. The chloroplast gene rbcL was sequenced for 62 species, which represent nearly 10% of living species diversity in the family. Taxa were chosen to reflect morphological, geographical, and ecological diversity. The analyses provide support for monophyly of subgenera Selaginella and Tetragonostachys. Stachygynandrum and Heterostachys are polyphyletic. Monophyly of Ericetorum is uncertain. Results also indicate a large number of new groupings not previously recognized on morphological grounds. Some of these new groups seem to have corresponding morphological synapomorphies, such as the presence of rhizophores (distinctive root-like structures), aspects of rhizophore development, and leaf and stem morphology. Others share distinctive ecological traits (e.g., xerophytism). For many groups, however, no morphological, ecological, or physiological markers are known. This could reflect patchy sampling and a lack of detailed knowledge about many species. Despite a lengthy fossil record dating from the Carboniferous Period, cladogram topology indicates that most of the living tropical species are probably the products of more recent diversifications. Resurrection plants, extreme xerophytes characterized by aridity-driven inrolling of branches and rapid revival on rehydration, have evolved at least three times in quite different clades.
|
|
| 9. |
- Korall, Petra, 1968-
(författare)
-
Phylogeny of Selaginellaceae
- 2003
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The phylogeny of Selaginellaceae, a small, but historically important family of heterosporous lycopods, has been the focus of this thesis. The approximately 700 extant species are herbaceous and distributed all over the world, with most species in the tropics and subtropics. Lycopods constituted a dominant element of the Upper Carboniferous flora, but Selaginellaceae were probably established already in the Lower Carboniferous some 345 million years ago, as revealed by macrofossil data. Major patterns of relationships were investigated based on a representative sample of global diversity and molecular (plastid gene rbcL, nuclear region 26S rDNA) and morphological data. Analyses were performed using parsimony and Bayesian inference. A survey of megaspore surface and wall structures was carried out for living species and included in the phylogenetic analyses. The resulting phylogenetic trees were used to evaluate various hypotheses on the evolution of the group, including the origins of tropical and temperate species diversity, as well as the evolution of xerophytism. Results showed that Selaginellaceae are monophyletic, and many subclades were identified. In a basal dichotomy two species, Selaginella selaginoides (L.) Link and S. deflexa Brackenridge, appear in a strongly supported clade as sister group to a clade comprising all other species (rhizophoric clade). The rhizophoric clade is recognised by the presence of rhizophores, which are highly characteristic root-like organs, and on the presence of decussately arranged sporophylls. Within the rhizophoric clade a basal dichotomy is most often found resulting in two more or less equally sized sister groups. These and many other groupings within these clades are new and have not previously been recognized in any other systematic study. Some of the new groups seem to have corresponding morphological synapomorphies, such as aspects of rhizophore development and megaspore characteristics. Others share distinctive ecological traits (e.g., xerophytism). For many groups, however, no morphological, ecological, or physiological markers are yet known.The inclusion of megaspore fossils allowed for tentative ages to be assigned to certain clades within the family. The phylogenetic tree is inconclusive with regard to a tropical or temperate origin of modern species diversity, but there is clear evidence for multiple independent origins of xerophytic strategies. Besides the phylogenetic results, this study reveals exceptionally high levels of substitution rates and rate heterogeneity in Selaginellaceae.
|
|
| 10. |
- Korall, Petra, 1968-, et al.
(författare)
-
Phylogeny of selaginellaceae : Evaluation of generic subgeneric relationships based on rbcL gene sequences
- 1999
-
Ingår i: International journal of plant sciences. - : University of Chicago Press. - 1058-5893 .- 1537-5315. ; 160:3, s. 585-594
-
Tidskriftsartikel (refereegranskat)abstract
- A cladistic analysis based on rbcL gene sequences from a representative sample of 18 species yields three most parsimonious trees that strongly support monophyly of Selaginellaceae. Within Selaginellaceae, the morphologically distinctive subgenus Selaginella is resolved as sister group to a clade composed of all other species, here termed the rhizophoric clade. In the rhizophoric clade, subgenus Stachygynandrum is paraphyletic to subgenera Ericetorum, Tetragonostachys, and Heterostachys. Monophyly of Ericetorum and Tetragonostachys is strongly corroborated. Results support a close relationship between "resurrection plants" in Stachygynandrum and the mat-forming or tufted drought-tolerant species of Tetragonostachys, indicating a common origin of xerophytism in these groups. A close relationship for all isophyllous species, as hypothesized in many classifications, is not supported by the rbcL data. Leaf isophylly and reduction in Ericetorum and Tetragonostachys most probably represent independent reversals of the marked anisophyllous condition in Stachygynandrum, Leaf reduction is one of a suite of characters that may have evolved in response to seasonal drought.
|
|
