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A new foraminiferal fauna is reported from the upper part of the Xiala Formation in the Zhari Namco section in the central Lhasa Block, which contains three species of fusulines and 26 species of small foraminifers. The presence of Reichelina and Codonofusiella in the fauna suggests a Wuchiapingian age. A review of the Lopingian faunas in several localities in the Lhasa Block indicates that this block was under a shallow marine environment during the Lopingian, rather than an uplifted terrestrial environment as previously recognized. The Lopingian palaeobiogeography as well as the sequences of the Lhasa Block differs greatly from the adjacent South Qiangtang, Karakorum and South Pamir blocks, and the Tethys Himalaya region of the Indian Plate. It further suggests that the Lhasa Block was separated from the South Qiangtang Block in the north by the Bangong‐Nujiang Ocean and the Tethys Himalaya area in the south by the Neotethys Ocean during the Lopingian time. Furthermore, the dissimilarity of the Guadalupian and Lopingian strata and faunas between the Lhasa and Karakorum blocks and similarity between the Lhasa and Tengchong blocks, may suggest that the Lhasa and Tengchong blocks were linked together during the Permian. [ABSTRACT FROM AUTHOR]

Benthic faunas and their palaeobiogeographic affinities related to climate gradient can provide insightful information to unravel the tectonic histories of their hosted blocks if they moved across different latitude zones. In this study, three different quantitative analyses (network, cluster and non-metric multi-dimensional scaling analyses) are employed to carry out a palaeobiogeographic study of the Kungurian–Roadian brachiopod faunas of the Cimmerian blocks. A spin-glass algorithm that enables network community detection is here used for the first time and its six groups-partition is considered as the optimal solution. Two new palaeobiogeographic subprovinces, the Southern and Northern Cimmerian subprovinces in the Southern Transitional Zone, are first recognised besides the previously perceived Cathaysian, Transhimalayan, Westralian and Austrazean provinces. Based on distinct palaeobiogeographic discrepancies, it is suggested that the Lhasa, Tengchong and Irrawaddy blocks, constituting the main parts of the Southern Cimmerian Subprovince, were probably situated near the peri-Gondwanan region; whereas the South Qiangtang, Baoshan and Sibuma blocks of the Northern Cimmerian Subprovince probably were located in the temperate region of the southern hemisphere during the Cisuralian to Guadalupian transition. Such discrepancies in palaeobiogeographic affinitites between two continental slices imply that the Meso-Tethys Ocean had existed before the late Cisuralian and its present oceanic remnants are represented by the Bangong-Nujiang Suture Zone in central Tibet, the Gaoligongshan shear zone in western Yunnan and the Medial-Myanmar Suture Zone in southern Myanmar and Peninsula Thailand. Moreover, the Neo-Tethys Ocean had likely co-existed with the Meso-Tethys Ocean during that time. Given that all these blocks were attached to the northern peri-Gondwanan margin during the early Cisuralian, the Kungurian-Roadian faunal discrepancies among different continental slices with a distinct latitude gradient can be interpreted by the allometric northward drifting of the Cimmerian blocks, which led to the formation of the Meso-Tethys and Neo-Tethys oceans. • A spin-glass algorithm for network community detection is applied for the first time in a palaeobiogeographic analysis. • The Southern and Northern Cimmerian subprovinces are first identified in the Tethys during the Kungurian–Roadian. • The Meso-Tethys Ocean had opened before late Cisuralian due to allometric northward drifting of the Cimmerian blocks. [ABSTRACT FROM AUTHOR]

• The age of the exotic limestone blocks within the Central Qiangtang Metamorphic Belt is late Kungurian to Roadian. • The exotic limestone blocks came from the Shuanghu type of Permian sequences in the South Qiangtang Block. • A strong subduction and accretion process happened during the closure of the Longmu Co-Shuanghu Paleotethys Ocean. The Central Qiangtang Metamorphic Belt (CQMB) is a subject of long-standing controversy for decades with respect to its origin and tectonic evolution. In this study, two foraminiferal faunas are reported from the exotic limestone blocks in the Jiaomuchaka and Jiangaizangbu sections within the CQMB. In total, 9 species of fusulines and 32 species of smaller foraminifers have been discovered in the Jiaomuchaka section, and 10 species of fusulines and 15 species of smaller foraminifers have been documented in the Jiangaizangbu section. In terms of the presence of the fusulines Pseudodoliolina ozawai , Presumatrina neoschwagerinoides , Neoschwagerina simplex and Afghanella sp., an age of late Kungurian to Roadian can be assigned to the faunas. A comparative study on the stratigraphic sequence and foraminiferal faunas between the exotic limestone blocks and contemporaneous deposits in the adjacent areas reveals that the exotic limestone blocks resemble strata of the Lugu Formation in the Shuanghu and Minzhuochaka areas in the South Qiangtang Block. The presence of these exotic limestone blocks within the CQMB suggests that the in-situ deposits of the Lugu Formation have been partly subducted beneath the North Qiangtang Block during the closing of the Paleotethys Ocean along the Longmu Co-Shuanghu Suture Zone. [ABSTRACT FROM AUTHOR]

Low air pressure and low oxygen partial pressure at high altitude seriously affect the survival and development of human beings and animals. ECE1 is a recently discovered gene that is involved in anti-hypoxia, but the full-length cDNA sequence has not been obtained. For a better understanding of the structure and function of the ECE1 gene and to study its effect in Tibetan pig, the cDNA of the ECE1 gene from the muscle of Tibetan pig was cloned, sequenced and characterized. The ECE1 full-length cDNA sequence consists of 2262 bp coding sequence (CDS) that encodes 753 amino acids with a molecular mass of 85,449 kD, 2 bp 5′UTR and 1507 bp 3′UTR. In addition, the phylogenetic tree analysis revealed that the Tibetan pig ECE1 has a closer genetic relationship and evolution distance with the land mammals ECE1 . Furthermore, analysis by qPCR showed that the ECE1 transcript is constitutively expressed in the 10 tissues tested: the liver, subcutaneous fat, kidney, muscle, stomach, heart, brain, spleen, pancreas, and lung. These results serve as a foundation for further insight into the Tibetan pig ECE1 gene. [ABSTRACT FROM AUTHOR]

A late Kungurian (Cisuralian, Permian) fauna including conodonts and fusulines is reported for the first time from the limestone units in the lower part of the Lugu Formation in the South Qiangtang Block (SQB) in Tibet. The conodonts include Mesogondolella siciliensis , M. qiangtangensis sp. nov., Sweetognathus subsymmetricus and S. guizhouensis. They all consistently indicate a late Kungurian age. The associated fusulines in the same interval include Armenina asiatica , Neoschwagerina simplex , Pseudodoliolina ozawai minima and Cancellina sp., which reliably indicate a Murgabian age. The coexistence of these conodonts and fusulines provides direct correlation between the base part of the Murgabian Stage in the fusuline-based Tethyan timescale and the late Kungurian Stage in the conodont-based international timescale. The conodont species S. subsymmetricus and S. guizhouensis together with the associated fusulines and brachiopods generally indicate a warm condition when the Lugu Formation was deposited, therefore, the SQB had incorporated into the equatorial warm water province during the late Kungurian. This contrasts with coeval cool water Vjalovognathus fauna from the basal part of the Xiala Formation in the Lhasa Block, the lower part of the Moulmein Limestone in the Hpa-An area in southern Myanmar and the Wandagee Formation in Western Australia. In addition, typical warm water Tethyan fusulines are absent in the Lhasa Block in the equivalent strata. These distinct faunal differences suggest that a wide Bangong-Nujiang Ocean between the SQB and the Lhasa Block probably existed during the late Kungurian. • A new late Kungurian conodont and fusuline fauna is reported from the South Qiangtang Block, Tibet. • The lower limestone units of the Lugu Formation are determined to be of late Kungurian in age. • The basal part of Murgabian Stage is correlative with the upper part of the Kungurian Stage. • The Bangong-Nujiang Ocean might have had a considerable width during the late Kungurian. [ABSTRACT FROM AUTHOR]

The paleogeographic evolution of the North Qiangtang Block during the Middle and Late Permian has been a contentious issue in recent decades. In this study, the Permian foraminiferal faunas were studied from the Raggyorcaka and Wangka areas in northern and eastern Tibet. The foraminifera from the Xueyuanhe Formation in the Raggyorcaka area suggest a Changhsingian rather than a Guadalupian (Middle Permian) age, as previously determined. A review of Permian strata in the North Qiangtang Block confirms the widespread onset of the Lopingian (Late Permian) paralic sedimentary facies containing gigantopterid plant fossils and the fusuline Palaeofusulina fauna, which lies unconformably over the different pre-Lopingian strata. The similar Lopingian facies and pronounced unconformity across the North Qiangtang and Simao blocks are interpreted as the initial collision between the Simao/Indochina and the South China blocks. • The age of the Xueyuanhe Formation in northern Tibet is early Changhsingian. • A significant onset of Lopingian paralic facies is recognized in the North Qiangtang Block. • The Simao/Indochina blocks may have collided with South China before the Lopingian. [ABSTRACT FROM AUTHOR]

The paleogeographic evolution of the Lhasa Block in northern Tibet during the Permian has been a contentious issue during the past decades. Several pioneering studies have highlighted the significance of faunas and their paleobiogeography in this block. In this paper, a new Middle Permian foraminiferal fauna is documented from the Xiala Formation in the Zhabuye area in the central Lhasa Block. This fauna is characterized by the presence of the Shanita - Hemigordiopsis foraminiferal assemblage, with its age to be the early Midian (Wordian) based on the coexisting fusulines Neoschwagerina craticulifera (Schwager), N. cheni Sheng and Kahlerina tenuitheca Wang, Sheng and Zhang. A review of the Shanita - Hemigordiopsis assemblage globally confirms that the age of this assemblage ranges from the late Murgabian to the Midian rather than extending into the Dzhulfian as previously recognized. This assemblage is widely distributed on the Cimmerian microcontinents and Gondwanan margin, but absent from the South China and Indochina blocks, which were approximately at the same latitude with Turkey in equatorial regions. Such a distribution pattern is better explained by the influence of oceanic currents flowing from equatorial regions to the Gondwanan margin along the Neotethys Ocean. It further suggests that the Neotethys Ocean may have opened by the Middle Permian to facilitate oceanic currents. • The age of Shanita-Hemigordiopsis foraminiferal assemblage is Middle Permian. • The distribution of Shanita is controlled by oceanic currents along Neotethys Ocean. • The Neotethys Ocean opened before the Middle Permian. [ABSTRACT FROM AUTHOR]