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The Beiya gold deposit is located in the central part of the Jinshajiang–Honghe strike–slip belt, at the junction zone of the Tethys-Himalaya orogenic belt and the Yangtze plate in SW China. This large-scale (125.6 million metric tonnes with a mean grade of 2.42 g/t) Au-rich polymetallic deposit is related to alkaline porphyry intrusions. Previous studies show that the Beiya alkaline porphyry intrusions are the fractionation product of a mantle-derived magma emplaced in an extension environment at the post-collision stage of the India–Eurasian plate collision; the Beiya deposit is considered to be skarn-related. Based on detailed field studies and previous work, we propose that the Beiya porphyry and associated Au-rich polymetallic ores were formed by the emplacement of magmas within the Jinshajiang–Honghe strike–slip fault during the late stage of the India–Eurasian plate collision at 45–25 Ma. At Beiya, the mineralized zones in the Cu–Au-rich porphyries are surrounded by Au–Cu–Fe skarns and Au (Cu) veins. Pb–Zn–Ag-rich mineralization was derived from the inner porphyry, and is widely developed outside the central alkaline-rich porphyry. The sulfur isotope signature of the sulfide mineralization in the Beiya and Qinhe deposits is − 2.40‰–4.50‰ and 1.25–2.75‰, respectively. These values are close to 0‰, indicating that the sulfur may be mantle-derived. The δ 18 O compositions of the ore-forming fluids responsible for the formation of calcites at Qinhe are 8.10‰–9.61‰, which is lower than that of Beiya (δ 18 O = 10.5‰) where the ores contain a larger contribution of oxygen from the mantle. The Beiya porphyry magmas provided fluids and the heat that drove the transport of the metals to the site of deposition. Alkaline porphyries are widely distributed throughout the Jinshajiang–Honghe strike–slip fault belt, and they are potential hosts to future discoveries of Beiya-style mineralization. [ABSTRACT FROM AUTHOR]

Dillenia indica Linn. is an endangered plant species occurring in southern Guangxi province and Yunnan province of China, which has been grown in gardens as an ornamental plant and is widely used in the medical field. Here, we report and characterize the complete plastid genome sequence of D. indica to provide genomic resources useful for promoting its conservation. The complete plastome is 159,266 bp in length and contains the typical structure and gene content of angiosperm plastome, including two inverted repeat (IR) regions of 26,457 bp, a large single-copy (LSC) region of 88,305 bp, and a small single-copy (SSC) region of 18,047 bp. The plastome contains 115 genes, consisting of 81 unique protein-coding genes, 30 unique tRNA genes, and 4 unique rRNA genes (5S rRNA, 4.5S rRNA, 23S rRNA, and 16S rRNA). The overall A/T content in the plastome of D. indica is 63.40%. The complete plastome sequence of D. indica will provide a useful resource for the conservation genetics of this species as well as for the phylogenetic studies of Dilleniaceae. [ABSTRACT FROM AUTHOR]

Clinacanthus nutans (Burm.f.) Lindau. is a medicinal species occurring in southern Guangdong province, Guangxi province, Hainan province and Yunnan province of China, which has been widely used in the medical field. However, its complete plastome information and systematic position are still unknown. In order to enhance the development of its medicinal value, we report and characterize the complete plastid genome sequence of C. nutans in an effort to provide genomic resources useful to promoting its medicinal value and systematic research. The complete plastome is 151,669 bp in length and contains the typical structure and gene content of angiosperm plastome, including two Inverted Repeat (IR) regions of 25,366 bp, a Large Single-Copy (LSC) region of 83,502 bp and a Small Single-Copy (SSC) region of 17,435 bp. The plastome contains 113 genes, consisting of 80 unique protein-coding genes, 29 unique tRNA gene and four unique rRNA genes (5S rRNA, 4.5S rRNA, 23S rRNA and 16S rRNA). The overall A/T content in the plastome of C. nutans is 61.60%. The complete plastome sequence of C. nutans will provide a useful resource for the conservation genetics of this species as well as for the phylogenetic studies of Acanthaceae. [ABSTRACT FROM AUTHOR]