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Final closure of the Palaeo‐Asian Ocean signifies the ultimate amalgamation of the North China, Tarim, Mongolia, Songliao, Xilinhot and other Central Asian blocks, and therefore, is critical in reconstructing the configuration of the Pangea supercontinent during the late Palaeozoic to early Mesozoic. However, the final closure time remains contentious. Here, we present a systematic palaeomagnetic study on the Upper Permian sedimentary sequences of the Xilinhot Block, located to the north of the Solonker Suture Zone. Rock magnetic results indicate stable pseudo‐domain magnetite is the dominant magnetic carrier. The characteristic components isolated between ~350 and 590°C display the existence of dual polarities. Combined with previous results, the merged site‐mean directions yield a negative reversal test and inconclusive fold tests. By comparing with coeval and posterior data, and correlating with stitching plutons that intruded the sampling sections, we argue for a remagnetization origin for the newly obtained data, which is most likely acquired during the thermal event when the stitching granitic plutons intruded at 242.0 ± 3.7 Ma. Then we synthesized available palaeomagnetic data from the Central Asian Orogenic Belt and adjacent blocks, and propose a Late Permian to Early Triassic final closure of the Palaeo‐Asian Ocean. Our reconstruction of Pangea in the Early Triassic negates the existence of a cut‐through seaway between the Mongol‐Okhotsk and Palaeo‐Asian Oceans. The Mongol‐Okhotsk Ocean was an extension of Panthalassa, in trumpet‐shaped and faced to the east, rather than an individual oceanic basin separating Siberia from the Cinamuria Block. [ABSTRACT FROM AUTHOR]

Dating the closure of the Paleo‐Asian Ocean (PAO) is critical to our understanding of East Asian tectonics during the formation of Pangea, yet existing estimates differ by up to 130 Myr (380–250 Ma). We report two robust paleomagnetic results from 320 to 280 Ma volcanic strata in the South Mongolia‐Xing'an Belt. Stable characteristic remanences of both results are likely primary and characterized by positive fold tests, consistent polarity with the Kiaman Superchron (∼318–262 Ma) and average paleosecular variation. The new results indicate that the northward motion of North China and Mongolia paralleled Laurussia from the Late Carboniferous to Early Permian. The N‐S width of the PAO in the east‐central segment (reference site: 43°N/114°E) was ca. 2,700 km during the Late Carboniferous to Early Permian. This wide ocean impeded floral and faunal exchange until the Guadalupian, prior to its final closure by ca. 250 Ma. Plain Language Summary: The Paleo‐Asian Ocean (PAO) separated North China and Tarim from Mongolia and Siberia. The closure timing is contentious and ranges from the Late Devonian to Early Triassic, resulting in great uncertainty when trying to reconstruct the Asian blocks in Pangea. Volcanic rocks are ideal recorders of paleomagnetic signals and therefore sought after to provide rigid paleogeographic reconstructions. In this study, we present paleomagnetic constraints on the paleolatitudes of blocks from the northern and southern sides of the PAO and propose a ca. 2700‐kilometer ocean of this segment of the PAO during 308–290 Ma. The existence of this wide oceanic basin impeded floral and faunal interchange between North China and Mongolia. The PAO finally closed and formed a unified North China‐Amuria block at ca. 250 Ma. Key Points: Mongolia was situated at 34.0°N during 320–296 Ma and 43.6°N during 300–280 MaThe N‐S width of the Paleo‐Asian Ocean (PAO) in the east‐central segment was ca. 2,700 km during the Late Carboniferous to Early PermianThe PAO impeded floral and faunal interchange until the Guadalupian, prior to its closure at ca. 250 Ma [ABSTRACT FROM AUTHOR]

[Display omitted] • Genomic landscape of 185 natural fermented dairy isolates in China and Mongolia. • Phylogenetics clades reflected high acid production potential or genome decay. • Growth score accurately predict acidification capability of S. thermophilus. Streptococcus (S.) thermophilus , an indispensable dairy starter, has been used in autochthonous as well as industrial milk fermentation. However, the genetic architecture underlying S. thermophilus traits and phenotypes is largely unknown. Here, we sequenced 185 S. thermophilus strains, isolated from natural fermented dairy products of China and Mongolia and used comparative genomic and genome wide association study to provide novel point for genetic architecture underlying its traits and phenotypes. Genome analysis of S. thermophilus showed association of phylogeny with environmental and phenotypic features and revealed clades with high acid production potential or with substantial genome decay. A few S. thermophilus isolated from areas with high chloramphenicol emissions had a chloramphenicol-resistant gene CatB8. Most importantly, we defined a growth score and identified a missense mutation G1118698T located at the gene Acn A that were both predictive of acidification capability of S. thermophilus. Our findings provide novel insight in S. thermophilus genetic traits, antibiotic resistant and predictive of acidification capability which both may had huge help in culture starter screening. [ABSTRACT FROM AUTHOR]