scholarly journals Leaf anatomy of a late Palaeozoic cycad

2017 ◽  
Vol 13 (11) ◽  
pp. 20170456 ◽  
Author(s):  
Zhuo Feng ◽  
Yong Lv ◽  
Yun Guo ◽  
Hai-Bo Wei ◽  
Hans Kerp
Keyword(s):  
Leaf Anatomy ◽  
Leaf Morphology ◽  
Yunnan Province ◽  
Southwest China ◽  
Upper Permian ◽  
Fossil Leaves ◽  
Leaf Surfaces ◽  
The Family ◽  
Clear Differentiation ◽  
Anatomical Evidence

Today, cycads are a small group of gymnospermous plants with a limited distribution in the (sub)tropics, but they were major constituents of Mesozoic floras. Fossil leaves sporadically found in latest Carboniferous and Permian floras have putatively been ascribed to cycads. However, their true affinity remains unclear due to the lack of anatomical evidence. Virtually all modern cycads have pinnate leaves, but this type of leaf morphology is by no means unique for cycads. Pinnate leaves of Plagiozamites oblongifolius Halle 1927 with well-preserved cuticles showing the epidermal anatomy are here described from the upper Permian Xuanwei Formation of Yunnan Province, Southwest China. The cuticles show a clear differentiation into costal and intercostal zones; stomata are confined to the intercostal zones on both the upper and lower leaf surfaces. The external morphology and the epidermal anatomy of these fossil leaves are closely comparable with those of extant cycads, particularly members of the family Zamiaceae.

New findings of ptyctimous mites of the family Steganacaridae (Acari, Oribatida, Phthiracaroidea) from Yunnan Province, Southwest China

2020 ◽  
Vol 25 (4) ◽  
pp. 658-667
Author(s):  
Dong Liu
Keyword(s):  
New Species ◽  
Yunnan Province ◽  
Southwest China ◽  
New Findings ◽  
The Family ◽  
Two New Species

Two new species of steganacarid mites (Oribatida: Phthiracaroidea) from Yunnan Province, Southwest China, Plonaphacarus chuxiongensis sp. nov. and Hoplophthiracarus jianchuanensis sp. nov., are described and illustrated. Keys to all known species of Plonaphacarus and Hoplophthiracarus from China are proposed to facilitate further studies of these groups.

scholarly journals DESCRIPTION OF A NEW SPECIES OF THE GENUS ANATEMNUS BEIER, 1932 (PSEUDOSCORPIONES: ATEMNIDAE) FROM CHINA

2016 ◽  
Vol 7 ◽  
pp. 567-572
Author(s):  
Zhizhong Gao ◽  
Feng Zhang
Keyword(s):  
New Species ◽  
Yunnan Province ◽  
Southwest China ◽  
Morphological Characters ◽  
The Family ◽  
A New Species ◽  
Detailed Diagnosis

A new pseudoscorpion species, Anatemnus reni sp. nov., belonging to the family Atemnidae Kishida, 1929, is reported from Yunnan Province, Southwest China. The detailed diagnosis, description and illustrations of important morphological characters are presented in this paper.

scholarly journals A new species of Platysiagum from the Luoping Biota (Anisian, Middle Triassic, Yunnan, South China) reveals the relationship between Platysiagidae and Neopterygii

2018 ◽  
Vol 156 (4) ◽  
pp. 669-682 ◽  
Author(s):  
W. WEN ◽  
S. X. HU ◽  
Q. Y. ZHANG ◽  
M. J. BENTON ◽  
J. KRIWET ◽  
...  
Keyword(s):  
Yunnan Province ◽  
Southwest China ◽  
Middle Triassic ◽  
New Materials ◽  
Western Tethys ◽  
The Family ◽  
Tethys Ocean ◽  
Anatomical Information ◽  
The Relationship ◽  
A New Species

AbstractFour complete platysiagid fish specimens are described from the Luoping Biota, Anisian (Middle Triassic), Yunnan Province, southwest China. They are small fishes with bones and scales covered with ganoine. All characters observed, such as nasals meeting in the midline, a keystone-like dermosphenotic, absence of post-rostral bone, two infraorbitals between dermosphenotic and jugal, large antorbital, and two postcleithra, suggest that the new materials belong to a single, new Platysiagum species, P. sinensis sp. nov. Three genera are ascribed to Platysiagidae: Platysiagum, Helmolepis and Caelatichthys. However, most specimens of the first two genera are imprints or fragmentary. The new, well-preserved specimens from the Luoping Biota provide more detailed anatomical information than before, and thus help amend the concept of the Platysiagidae. The Family Platysiagidae was previously classed in the Perleidiformes. Phylogenetic analysis indicates that the Platysiagidae is a member of basal Neopterygii, and its origin seems to predate that of Perleidiformes. Moreover, platysiagid fishes are known from the Middle Triassic of the western Tethys region. The newly found specimens of platysiagids from Luoping provide additional evidence that both eastern and western sides of the Tethys Ocean were biogeographically more connected than previously thought.

scholarly journals Genetic diversity and population structure of rice stripe virus in China

2009 ◽  
Vol 90 (4) ◽  
pp. 1025-1034 ◽  
Author(s):  
Tai-Yun Wei ◽  
Jin-Guang Yang ◽  
Fu-Long Liao ◽  
Fang-Luan Gao ◽  
Lian-Ming Lu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Population Structure ◽  
Yunnan Province ◽  
Southwest China ◽  
Eastern China ◽  
Rice Stripe Virus ◽  
Genetic Distances ◽  
Geographical Regions ◽  
Strong Negative Selection ◽  
Recent Outbreak

Rice stripe virus (RSV) is one of the most economically important pathogens of rice and is repeatedly epidemic in China, Japan and Korea. The most recent outbreak of RSV in eastern China in 2000 caused significant losses and raised serious concerns. In this paper, we provide a genotyping profile of RSV field isolates and describe the population structure of RSV in China, based on the nucleotide sequences of isolates collected from different geographical regions during 1997–2004. RSV isolates could be divided into two or three subtypes, depending on which gene was analysed. The genetic distances between subtypes range from 0.050 to 0.067. The population from eastern China is composed only of subtype I/IB isolates. In contrast, the population from Yunnan province (southwest China) is composed mainly of subtype II isolates, but also contains a small proportion of subtype I/IB isolates and subtype IA isolates. However, subpopulations collected from different districts in eastern China or Yunnan province are not genetically differentiated and show frequent gene flow. RSV genes were found to be under strong negative selection. Our data suggest that the most recent outbreak of RSV in eastern China was not due to the invasion of new RSV subtype(s). The evolutionary processes contributing to the observed genetic diversity and population structure are discussed.

Cassiavellia galtarae, new species, new genus: a new Permian bivalve and its significance for pterioidean systematics

2010 ◽  
Vol 84 (6) ◽  
pp. 1152-1176 ◽  
Author(s):  
Ilya Tëmkin ◽  
John Pojeta
Keyword(s):  
New Species ◽  
New Genus ◽  
Larval Shell ◽  
Upper Permian ◽  
Taxonomic Significance ◽  
New Genus And Species ◽  
The Family ◽  
Dental Ontogeny

An exceptionally well-preserved silicified bivalve from the Upper Permian of Texas is described and assigned to a new genus and species,Cassiavellia galtarae, placed in the family Bakevelliidae. The species represents one of the earliest and best characterized unequivocal occurrences of the multivincular ligament in the superfamily Pterioidea. The silicified material provides a wealth of information on the morphology of inadequately known Paleozoic pterioideans, including hitherto undescribed aspects of the larval shell, auricular sulcus, muscle scars, and dental ontogeny. The discovery of the condyle-fossa complex on the anteroventral shell margin, a feature previously undescibed in Bivalvia, raises the question of the homology and taxonomic significance of the problematic subumbonal ridge-like structures in Pterioidea. In life,C. galtaraewas probably an epifaunal right-pleurothetic bivalve, byssally attached to hard or raised flexible substrata. In addition toC. galtarae, another new species,C. nadkevnae, is placed inCassiavellia.

scholarly journals Acronema crassifolium sp. nov. (Apiaceae), a distinct new species from Yunnan, southwest China

Phytotaxa ◽  
2013 ◽  
Vol 87 (3) ◽  
pp. 39
Author(s):  
HUAN-CHONG WANG ◽  
XIN-MAO ZHOU ◽  
HANG SUN ◽  
YUE-HUA WANG
Keyword(s):  
New Species ◽  
Pollen Morphology ◽  
Yunnan Province ◽  
Southwest China

Acronema crassifolium, a distinct new species endemic to Yunnan province, China, is described and illustrated. It is characterized by its thickly papery, ternate, abaxially dark purple leaves, terminal umbels with 8–13 rays, and absent calyx teeth. The pollen morphology of the new species is also described in this study.

A review of the non-lyctine powder-post beetles of Yunnan (China) with a new genus and new species (Coleoptera: Bostrichidae)

Zootaxa ◽  
2022 ◽  
Vol 5091 (4) ◽  
pp. 501-545
Author(s):  
YI-FENG ZHANG ◽  
LING-ZENG MENG ◽  
ROGER A. BEAVER
Keyword(s):  
New Species ◽  
Southeast Asia ◽  
Yunnan Province ◽  
New Genus ◽  
Southwest China ◽  
Geological History ◽  
Yunnan Region ◽  
Palearctic Region ◽  
History Of ◽  
First Time

The powder post beetles (Coleoptera: Bostrichidae) (except Lyctinae) of Yunnan Province in Southwest China are reviewed for the first time. Keys to twenty-six genera and fifty-two species from the Yunnan region are provided. One new genus and seven new species are described: Dinoderus (Dinoderastes) hongheensis sp. nov., Dinoderus (Dinoderastes) nanxiheensis sp. nov., Gracilenta yingjiangensis gen. nov., sp. nov., Calonistes vittatus sp. nov., Calophagus colombiana sp. nov., Xylodrypta guochuanii sp. nov. and Xylodrypta zhenghei sp. nov.. Fourteen species are recorded in China for the first time. The bostrichid fauna of Yunnan is compared with those of the neighbouring bio-geographically related Southeast Asian and Himalayan regions. The fauna has a close affinity with that of tropical Southeast Asia and a much weaker relationship with the Palearctic region. The differences with the Himalayas may reflect the separate evolutionary and complex geological history of the two areas.

Sign in / Sign up

Export Citation Format

Share Document