New data on the biostratigraphy of the Early Devonian “Spirifer” tonkinensis brachiopod fauna in South China and adjacent region

Devonian palaeoecosystems and palaeoenvironments of South China

“…The well-known BSpirifer^tonkinensis fauna is the most diverse and widespread Early Devonian brachiopod fauna in South China, and characterised by the occurrence of endemic Rostrospirifer and Dicoelostrophia as well as over 30 other associated genera (around 70 species), but its temporal and spatial distribution remain under debate (Wang and Rong 1986;Hou and Ma 2005). Through the studies on conodont and brachiopod biostratigraphy at the Mode and Poyuan sections, in combination with previous studies, Guo et al (2019) suggested the entries of the BSpirifer^tonkinensis fauna were diachronous and consistent with the northeastward transgression in South China and adjacent areas during Early Devonian. The fauna may originated in northern Vietnam and then spread northwards into South China.…”

“…Based on a multivariate morphometric analysis, Liang et al (2019) identified four morphospecies of syringoporoid tabulate corals in the upper to uppermost Famennian Etoucun Formation at the Huilong section, Guilin, including Chia hunanensis, Tetraporinus virgatus, Fuchungopora multispinosa, and F. huilongensis n. sp. The corals are commonly tilted or overturned, indicating the tabulate corals settled on a soft substrate, and were subject to periodic high-energy conditions on the isolated Guilin carbonate platform.…”

Lower Emsian (Lower Devonian) conodonts from southwestern and central Guangxi, South China: Implications for palaeogeographic reconstructions

“…In the Dale section, the middle excavatus subzone is supposed to include the Xiaoshan Formation to lower Tonggeng Member of Yujiang Formation (Guo et al, 2019). The Xiaoshan Formation consists of sandstone and siltstone with tabular cross-and horizontal beddings, yielding trace fossils; the overlying lower Tonggeng Member of the Yujiang Formation is composed of mudstone and argillaceous siltstone with algal laminae, containing pyrites, and various fossils (bivalves, brachiopods, and trilobites) (Bai et al, 1982(Bai et al, , 1994.…”

“…In Nandan area of northern Guangxi, evident sedimentary facies turnover is recorded in the Yilan Formation (Guo et al, 2015(Guo et al, , 2018. The lower and middle parts of the Yilan Formation consist of purple to brownish-yellow calcareous mudstone, grey marlstone, and nodular limestone yielding the "Spirifer" tonkinensis brachiopod fauna, a diverse neritic fauna widely distributed in the epicontinental sea of southern China during the Early Devonian (Guo et al, 2019). While the upper part of the Yilan Formation (correlated to the nothoperbonus Zone) is composed of dark grey mudstone with lenses of marlstone and calcareous concretions, containing small-sized monotonous brachiopod fauna, abundant thin-shelled tentaculitids, sporadic nautiloids and gastropods, and abundant pyrites in both sediments and interiors of brachiopods (Guo et al, 2015).…”

“…In the last century, many studies on the Lower Devonian conodonts in the South China Plate were accomplished (Bai, Bai, Ma, Wang, & Sun, 1994; Bai, Jin, & Ning, 1982; Bai, Jin, Ning, He, & Han, 1979a, 1979b; Gong, 1992; Jiang, Hu, & Zheng, 1996; C. Y. Wang, 1981; C. Y. Wang et al, 1979; C. Y. Wang & Wang, 1978; Xiong, 1981), elaborating the basic conodont biostratigraphy framework of South China. In the late 2010s, more studies were carried out (Guo, Nie, & Sun, 2018, 2019; Lu & Chen, 2016; Lu, Qie, & Chen, 2016; Lu, Qie, Yu, & Chen, 2017; Lu, Valenzuela‐Ríos, Liao, & Kuang, 2018; Lu, Valenzuela‐Ríos, Liao, & Wang, 2019; Lu, Valenzuela‐Ríos, Wang, Liao, & Wang, 2019) with the purpose to better understand the Lower Devonian conodont biostratigraphy and evolution of early polygnathids and to search for the basal Emsian boundary in South China as well.…”