Topic
Osmoxylon
About: Osmoxylon is a research topic. Over the lifetime, 6 publications have been published within this topic receiving 208 citations.
Papers
TL;DR: Phylogenetic analyses of ITS sequence data do not support the widely used traditional division of Araliaceae into three tribes, and topologies suggest that biogeographic radiations into different tropical/subtropical regions and into the north and south temperate regions occurred early in the history of core Arali growers.
Abstract: Phylogenetic analyses of ITS sequence data from 70 species and 40 genera of Araliaceae (representing all major lineages within the ''core group'' of the family) do not support the widely used traditional division of Araliaceae into three tribes. Tribe Aralieae (characterized by imbricate petals) is found nested within a paraphyletic Schefflerieae (whose taxa have valvate petals). There are, however, two large monophyletic groups comprising most araliad genera: the ''Aralia-Polyscias-Pseudopanax group'' (which in- cludes Aralia, Meryta, Munroidendron, Panax, Pentapanax, Polyscias, Pseudopanax, Reynoldsia, Sciadodendron, Tetra- plasandra, and their close allies), and the ''Eleutherococcus-Dendropanax-Schefflera group'' (including Brassaiopsis, Dendropanax, Eleutherococcus, Fatsia, Hedera, Oreopanax, Schefflera, Sinopanax, and their close allies). The ITS trees also permit a re-evaluation of several taxonomically important morphological characters (e.g., petal aestivation, leaf architecture, carpel number, and habit), and provide the opportunity to assess traditional generic delimitations in the family. Four of the largest genera appear to be either polyphyletic (Schefflera, Pseudopanax) or paraphyletic (Aralia, Polyscias), but further studies will be needed to fully re-define these complex taxa. Outgroup comparisons and the placement of Astrotricha and Osmoxylon (in basally-branching lineages in Araliaceae) help to confirm a paleotropical origin of the family. The ITS topologies suggest that biogeographic radiations into different tropical/subtropical regions and into the north and south temperate regions occurred early in the history of core Araliaceae. Temperate taxa have arisen several times indepen- dently from tropical and subtropical relatives, although a few subtropical taxa may be found nested within temperate clades (e.g., Pentapanax within Aralia). Migrations between the Old and New Worlds are also sug- gested for several taxa, including Aralia, Panax, Oplopanax, and the Sinopanax—Oreopanax generic pair.
146 citations
TL;DR: Phylogenetic analyses of the combined plastid and ITS data supported the results of the previously studies that the Chinese members of Araliaceae were scattered within the Asian Palmate group and the Aralia‐Panax group with Osmoxylon at the base of core Arali Families.
Abstract: Chinese Araliaceae consist of 20 genera and ca. 175 species. To assess the evolutionary relationships of Araliaceae and their biogeographic diversification in China, the phylogeny of Chinese Araliaceae was constructed by sampling 96 accessions representing 20 genera and 50 species of Chinese Araliaceae and 45 closely related taxa using sequences of the nuclear ribosomal internal transcribed spacer (ITS) region and six plastid regions (the ndhF gene, the trnL-trnF region, the rps16 intron, the atpB-rbcL intergenic spacer, the rpl16 intron, and the psbA-trnH intergenic spacer). Phylogenetic analyses of the combined plastid and ITS data supported the results of the previously studies that the Chinese members of Araliaceae were scattered within the Asian Palmate group and the Aralia-Panax group with Osmoxylon at the base of core Araliaceae. The generic status of Pentapanax and Tupidanthus is not supported. Our analysis clearly places them in Aralia and Asian Schefflera, respectively. In a broader phylogenetic framework of Araliaceae, based on the fossil-calibrated Bayesian dating, Chinese Araliaceae was inferred to have originated in Asia and underwent a rapid radiation in its evolutionary history. Its diversification is hypothesized to have been driven largely by the orogenies in Asia during the Cenozoic. In China, the distribution pattern of the phylogenetic diversity of Araliaceae corresponds with its taxonomic diversity across the entire region.
27 citations
Journal Article•
TL;DR: The analysis suggests a diffuse origin of Araliaceae taxa, with many genera belong to the Asian palmate clade or the tribe Hedereae, and expanded sampling of Arthrophyllum continues to support its monophyly.
Abstract: We employ the nuclear ribosomal ITS sequences to assess the evolutionary relationships of Araliaceae in the Malesian region. Malesian Araliaceae consist of 14 genera and about 500 species. Our analysis suggests a diffuse origin of Araliaceae taxa, with many genera belong to the Asian palmate clade or the tribe Hedereae. The Malesian endemic Harmsiopanax is morphologically unique and its phylogenetic position is not well resolved at present. Several morphologically diverse species of Brassaiopsis perhaps have a relatively recent origin in the Malay Peninsula and Sumatra, as suggested by their monophyly as well as their low ITS sequence divergence. Wardenia is not supported as W.simplex (=B.simplex) is nested within Brassaiopsis. The Malayan region is important for the development of Schefflera, and available evidence suggests that Schefflera in the region forms a clade with the Heptapleurum group. Dendropanax lancifolius does not form a clade with the core group of Dendropanax, and its status needs to be further analyzed. Macropanax maingayi was considered to be a highly distinct member comprising the monotypic genus Hederopsis. Our analysis clearly places it in Macropanax. Aralia merrillii was once considered to be the sole member of the genus Acanthophora because of its unusual climbing habit. The ITS data support its placement in Aralia. Our expanded sampling of Arthrophyllum continues to support its monophyly. Osmoxylon has a primary distribution in the Malesian region and it is a hylogenetically isolated member of Araliaceae.
12 citations
Journal Article•
TL;DR: A synopsis is given of the genus Osmoxylon, Araliaceae, in Malesia and the Bismarck Archipelago, including also one species of the Solomon Islands, where nine new species have been described and 20 new combinations appeared to be necessary.
Abstract: A synopsis is given of the genus Osmoxylon, Araliaceae, in Malesia and the Bismarck Archipelago, including also one species of the Solomon Islands.
In the introduction arguments are given why the genus Boerlagiodendron is merged with Osmoxylon.
In all 41 species are recognized and are keyed out. Of each species the synonymy is given, as well as the distribution and collections examined; sometimes critical notes on affinity and variability are added. Two names of which the types are apparently lost and which could not be satisfactorily placed are added as insufficiently known.
Nine new species have been described and 20 new combinations appeared to be necessary.
Full descriptions of all species will appear in the Flora Malesiana treatment of Araliaceae to which this paper is a precursor.
7 citations
TL;DR: Osmoxylon Miq.
Abstract: Osmoxylon Miq. (Araliaceae) is revised for Palau, Micronesia including descriptions of two new taxa Osmoxylon leidichii Costion, sp. nov. and Osmoxylon ngardokense Costion, sp. nov. Full descriptions are provided for all four Palau species, along with diagnostic field keys.
4 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2016 | 2 |
| 2008 | 1 |
| 2004 | 1 |
| 2001 | 1 |
| 1976 | 1 |