Shenzhen Fairy Lake Botanical Garden
Shenzhen Fairy Lake Botanical Garden
Yang Y.,CAS Institute of Botany |
Lin L.-B.,China Railway Group Ltd |
Ferguson D.K.,University of Vienna |
Zhang S.-Z.,Shenzhen Fairy Lake Botanical Garden |
Wan T.,Shenzhen Fairy Lake Botanical Garden
Cretaceous Research | Year: 2017
Modern gnetophytes consist of three families, i.e. the Ephedraceae, the Gnetaceae, and the Welwitschiaceae, which show diversified morphology. The basal group Ephedraceae possesses an extremely reduced female cone with only the uppermost pair/whorl being fertile, while both the Gnetaceae and the Welwitschiaceae bear female cones/spikes with multiple whorls of fertile bracts. Here, we describe a new ephedroid macrofossil, Liaoningia decussata Yang et Lin, gen. et sp. nov., from the Lower Cretaceous Yixian Formation of western Liaoning in China. This species has typical ephedroid morphology, e.g. the dichasial branching shoot system, swollen nodes, internodes having many fine longitudinal striations, and decussate phyllotaxy, lengthy linear leaves possessing two parallel veins, and female cones consisting of paired bracts. This new genus is similar to the Ephedraceae in its vegetative organs, but differs from the latter by the female spikes with multiple pairs of fertile bracts. In this respect Liaoningia is similar to both the Gnetaceae and the Welwitschiaceae, but distinctly differs from the latter two genera in its vegetative organs. As a result, our new genus shows intermediate morphology between the Ephedaceae and the other two families of the gnetophytes, and is probably a missing link in the evolutionary process from the Ephedraceae to the clade including the Gnetaceae and the Welwitschiaceae. © 2017 Elsevier Ltd
He X.,Sun Yat Sen University |
Jin J.,Sun Yat Sen University |
Wang S.,CAS Institute of Botany |
Wang S.,CAS Nanjing Institute of Geology and Palaeontology |
And 3 more authors.
International Journal of Plant Sciences | Year: 2010
A marattialean trunk of Psaronius laowujiensis sp. nov. is described from the Upper Permian of the Xuanwei Formation, Panxian County, Guizhou Province, South China. The specimen most likely represents the lower part of the trunk, because the preserved thickness of the root mantel is somewhat larger than the diameter of the stem. Meristeles of the stem are arranged in approximately five tangential stelar cycles but not in radial files. Inner meristeles are in small number, ;12-13, and loosely arranged. Leaf traces diverge helically and are organized in a 2/5 phyllotaxy. The leaf base vascular configuration consists of three strands that include a large U-shaped, centrifugal strand, a small centripetal strand, and an inverted V-shaped internal strand. A vascular bundle sheath one or two cell layers thick surrounds each meristele. Within the centripetal concavity of each peripheral cauline bundle there are anchor-shaped sclerenchymatous strands. Ground tissue appears to consist of aerenchymatous parenchyma, in which secretory cavities are dispersed. Bound roots mostly possess seven to nine protoxylem poles. The vascular bundle sheath is one or two cell layers thick. The inner cortex consists of aerenchymatous parenchyma. A detailed comparison of the present specimen with known species of Psaronius from the Permian of South China is made. Our specimen is similar to Psaronius wangii in many aspects, but the two can be clearly distinguished by the structure of the ground tissue of the stem and the leaf base vascular configuration, which leads to the erection of a new species, P. laowujiensis, for this specimen. Certain important characters in species from the Permian of South China are discussed. The tree- or anchor-shaped sclerenchymatous configuration within the centripetal concavity of the peripheral cauline bundles is unique to species from the South China Permian. The permanent vascular bundle sheath surrounding the meristeles of the stem and the stele of the root is another remarkable feature of those species. The analogous tissue, termed "inner cortex" by certain authors, is also present in some Psaronius from the Euramerican and North China floras, but in those cases it is thinner walled and not as remarkable as the vascular bundle sheath in the species from South China. The leaf base vascular configuration of the species from the Permian in South China is more diverse than those from other places. © 2010 by The University of Chicago. All rights reserved.
PubMed | CAS Institute of Botany, Missouri Botanical Garden, University of Chinese Academy of Sciences, CAS Xishuangbanna Tropical Botanical Garden and 2 more.
Type: | Journal: Molecular phylogenetics and evolution | Year: 2017
Taiwan is a continental island lying at the boundary between the Eurasian and the Philippine tectonic plates and possesses high biodiversity. Southern Taiwan, viz. Hengchun Peninsula, is notably floristically different from northern Taiwan. The floristic origin and relationships of the Hengchun Peninsula have been rarely investigated in a phylogenetic context. In this study, data from six plastid and nuclear sequences were used to reconstruct phylogenetic relationships within Burasaieae (Menispermaceae), which mainly inhabits tropical rainforests. The tree-based comparisons indicate that the position of Tinospora sensu stricto conflicts significantly between the cpDNA and ITS trees. However, alternative hypothesis tests from the ITS data did not reject the result of the cpDNA data, which suggests that tree-based comparisons might sometimes generate an artificial incongruence, especially when markers with high homoplasy are used. Based on the combined cpDNA and ITS data, we present an inter-generic phylogenetic framework for Burasaieae. Sampled species of Tinospora are placed in three different clades, including Tinospora dentata from southern Taiwan and T. sagittata from mainland China in an unresolved position alongside six lineages of Burasaieae. By integrating lines of evidence from molecular phylogeny, divergence times, and morphology, we recognize the three Tinospora clades as three different genera, including Tinospora sensu stricto, a new genus (Paratinospora) for T. dentata and T. sagittata, and Hyalosepalum resurrected. Tinospora dentata, now endemic to the Hengchun Peninsula, originated from the Late Eocene (ca. 39 Ma), greatly predating the formation of Taiwan. Our study suggests that the flora of the Hengchun Peninsula contains some ancient components that might have migrated from mainland China.
Zhang W.,Shenyang Institute of Geology and Mineral Resources |
Yang X.-J.,CAS Nanjing Institute of Geology and Palaeontology |
Fu X.-P.,Shenzhen Fairy Lake Botanical Garden |
Zheng S.-L.,Shenyang Institute of Geology and Mineral Resources |
And 2 more authors.
Review of Palaeobotany and Palynology | Year: 2012
A new fossil cycad stem Sinocycadoxylon liianum gen. et sp. nov. is described based on a well-preserved petrified specimen collected from the Middle Jurassic of Beipiao, Liaoning Province, China. The stem is composed of a small pith, a polyxylic vascular cylinder and cortex. The pith is parenchymatous with medullary vascular bundles, transfusion cells and mucilage canals. The polyxylic vascular cylinder consists of sixteen centrifugal rings and one centripetal vascular ring, all with distinct growth rings in secondary xylem. The presence of polyxyly with growth rings distinguishes this new genus from all fossil and extant Cycadales. The primary xylem is mesarch. Secondary xylem tracheids have araucarioid radial pitting. The rays are uni- or multiseriate and the latter are usually accompanied by mucilage canals and transfusion cells. This polyxylic stem is believed to be related to the Encephalartoideae of Zamiaceae. The new find provides new insights into cycad evolution which is consistent with former phylogenetic analyses indicating that Cycadales originated form Medullosales. © 2012 Elsevier B.V.
Kuang D.-Y.,Shenzhen Fairy Lake Botanical Garden |
Kuang D.-Y.,South China Agricultural University |
Wu H.,South China Agricultural University |
Wang Y.-L.,CAS South China Botanical Garden |
And 4 more authors.
Genome | Year: 2011
Here, we report a completely sequenced plastome using Illumina/Solexa sequencing-by-synthesis (SBS) technology. The plastome of Magnolia kwangsiensis Figlar & Noot. is 159 667 bp in length with a typical quadripartite structure: 88 030 bp large single-copy (LSC) and 18 669 bp small single-copy (SSC) regions, separated by two 26 484 bp inverted repeat (IR) regions. The overall predicted gene number is 129, among which 17 genes are duplicated in IR regions. The plastome of M. kwangsiensis is identical in its gene order to previously published plastomes of magnoliids. Furthermore, the C-to-U type RNA editing frequency of 114 seed plants is positively correlated with plastome GC content and plastome length, whereas plastome length is not correlated with GC content. A total of 16 potential putative barcoding or low taxonomic level phylogenetic study markers in Magnoliaceae were detected by comparing the coding and noncoding regions of the plastome of M. kwangsiensis with that of Liriodendron tulipifera L. At least eight markers might be applied not only to Magnoliaceae but also to other taxa. The 86 mononucleotide cpSSRs that distributed in single-copy noncoding regions are highly valuable to study population genetics and conservation genetics of this endangered rare species. © 2011 Published by NRC Research Press.
PubMed | Shenzhen Fairy Lake Botanical Garden
Type: Journal Article | Journal: Genome | Year: 2011
Here, we report a completely sequenced plastome using Illumina/Solexa sequencing-by-synthesis (SBS) technology. The plastome of Magnolia kwangsiensis Figlar & Noot. is 159667 bp in length with a typical quadripartite structure: 88030 bp large single-copy (LSC) and 18669 bp small single-copy (SSC) regions, separated by two 26484 bp inverted repeat (IR) regions. The overall predicted gene number is 129, among which 17 genes are duplicated in IR regions. The plastome of M. kwangsiensis is identical in its gene order to previously published plastomes of magnoliids. Furthermore, the C-to-U type RNA editing frequency of 114 seed plants is positively correlated with plastome GC content and plastome length, whereas plastome length is not correlated with GC content. A total of 16 potential putative barcoding or low taxonomic level phylogenetic study markers in Magnoliaceae were detected by comparing the coding and noncoding regions of the plastome of M. kwangsiensis with that of Liriodendron tulipifera L. At least eight markers might be applied not only to Magnoliaceae but also to other taxa. The 86 mononucleotide cpSSRs that distributed in single-copy noncoding regions are highly valuable to study population genetics and conservation genetics of this endangered rare species.