+Model PALWOR-358; No. of Pages 16 ARTICLE IN PRESS Available online at www.sciencedirect.com ScienceDirect Palaeoworld xxx (2016) xxx–xxx Age and distribution of the Late Devonian brachiopod genus Dzieduszyckia Siemiradzki, 1909 in southern China a a a,∗ a b Ting Nie , Wen Guo , Yuan-Lin Sun , Bing Shen , Bao-An Yin , b b b b Zhuan-Hong Tang , Yu-Kun Li , Xiang-Lin Huang , Chi Mai a School of Earth and Space Sciences, Peking University, Beijing 100871, China b Regional Geological Survey of Guangxi, Guilin 541003, Guangxi, China Received 8 December 2015; received in revised form 5 March 2016; accepted 25 March 2016 Abstract Conodont biostratigraphical work was done at four sections recently found with occurrence of the rhynchonellide brachiopod genus, Dzieduszy- ckia Siemiradzki, in southern Guangxi and in the border area between Dushan County of Guizhou and Nandan County of Guangxi, South China. These sections represent two different types of facies, i.e., carbonate platform and intraplatform basin. The conodont analysis reveals that this genus occurs in the Upper triangularis Zone and the Middle crepida Zone at the Dazhai Section, through the Lower to Upper crepida zones at Dalong, and is restricted within the Upper rhomboidea Zone at the two intraplatform basin sections (Changtang and Duli). This result demonstrates that the occurrence of these peculiar rhynchonellide brachiopods in South China, regardless of the depositional environments, is within the Lower Famennian instead of the previously suggested Upper Famennian. Furthermore, this brachiopod genus in South China began to inhabit on the carbonate platform almost since the beginning of the Famennian and did not extend to the intraplatform basin facies until the late Early Famennian. Available biostratigraphic data indicate that during the Early and Middle Famennian, Dzieduszyckia is widely distributed not only in South China, but also throughout the world, such as Morocco and southern Ural. Observation on the new collections from the four studied sections reveals that the peculiar rhynchonellide brachiopods have a great morphological variation within each section. Significant differences existed among the collections from different sedimentary settings and localities, probably reflecting the environmental and geographic constraint on the morphology of Dzieduszyckia. Samples from different lay- ers in the same section have nearly identical morphological variation, suggesting the temporal inheritance in morphology of the rhynchonellide brachiopod. © 2016 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. All rights reserved. Keywords: Conodont biostratigraphy; Dzieduszyckia; Brachiopods; Famennian; South China 1. Introduction southern Ural, Kazakhstan, and South China (Nalivkin, 1947; Rozman, 1962; Biernat, 1967; Cloud and Boucot, 1971; Ager Dzieduszyckia is one of the largest Paleozoic rhynchonel- et al., 1976; Xian and Jiang, 1978; Noll et al., 1984; Balinski´ loids, characterized by bisulcate, strongly costate shell. It has and Biernat, 2003). Dzieduszyckia is normally discovered as been reported from United States, Mexico, Morocco, Poland, monospecific fauna. As such, it is widely accepted that this genus might inhabit in a cold-seep related environment (Ager et al., 1976; Campbell and Bottjer, 1995; Peckmann et al., 2007). ∗ Corresponding author. Tel.: +86 10 62754151; fax: +86 10 62754151. In South China, Dzieduszyckia was previously reported only E-mail addresses: yinge [email protected] (T. Nie), [email protected] from three localities: Dayao of Puding County (Xian and Jiang, (W. Guo), [email protected] (Y.L. Sun), [email protected] 1978), Daihua of Changshun County (Xian et al., 1980) and (B. Shen), [email protected] (B.A. Yin), [email protected] Jialiantang of Dushan County (Xian and Jiang, 1978) (marked (Z.H. Tang), [email protected] (Y.K. Li), [email protected] as localities 1–3 in Fig. 1). All three localities were situated (X.L. Huang), [email protected] (C. Mai). http://dx.doi.org/10.1016/j.palwor.2016.03.005 1871-174X/© 2016 Elsevier B.V. and Nanjing Institute of Geology and Palaeontology, CAS. All rights reserved. Please cite this article in press as: Nie, T., et al., Age and distribution of the Late Devonian brachiopod genus Dzieduszyckia Siemiradzki, 1909 in southern China. Palaeoworld (2016), http://dx.doi.org/10.1016/j.palwor.2016.03.005 +Model PALWOR-358; No. of Pages 16 ARTICLE IN PRESS 2 T. Nie et al. / Palaeoworld xxx (2016) xxx–xxx Fig. 1. Sketched Late Devonian paleogeographic map of Guangxi and southern Guizhou, China, showing distribution of Dzieduszyckia in South China. 1. Dayao of Puding; 2. Daihua of Changshun; 3. Jialiantang (Xiasi) of Dushan; 4. Changtang (Mawei) of Dushan; 5. Duli (Liuzhai) of Nandan; 6. Dazhai (Xiasi) of Dushan; 7. Dalong of Tiandeng. in the inter-platform basin named as Shui-Nan (Shuicheng- study and geochemical analysis of the collections will be Nandan) Basin during the Late Devonian and the brachiopod presented elsewhere. Dzieduszyckia was discovered in the lower part of the Daihua Formation (now revised as Wuzhishan Formation). Based on 2. Geological background and fossil localities the material from Dayao and Jialiantang, four Dzieduszyckia species were established with a very brief description in the Guangxi and southern Guizhou provinces are the most impor- Chinese Paleontological Atlas of Guizhou Province (Xian and tant areas in China for the study of Devonian biostratigraphy Jiang, 1978). The rhynchonellide brachiopods from the Daihua and paleontology. The Devonian transgression initiated from Section have not been formally described yet, but are variably the Qin-Fang (Qinzhou-Fangcheng) remnant trough in southern recorded as Leiorhnchus baschkirica, Eoperegrinella baschkir- Guangxi and expanded progressively northwards on the South ica, or Dzieduszyckia baschkirica in literature (Sun and Shen, China plate (e.g., Wu in Zhong et al., 1992; Chen et al., 2001a). 1965; Xian et al., 1980; Hou et al., 1985; GZGMRB, 1987). In The transgression only reached the central and western parts of the Daihua section, Dzieduszyckia occurs more than ten meters Guangxi during the Early Devonian, whereas the central parts of below the typical upper Famennian ammonoid faunas charac- Guizhou and Hunan provinces were submerged in the Middle terized with Clymenia and Wocklumeria (Sun and Shen, 1965; Devonian. From the late Early Devonian (Emsian), especially Ran, 1981). Wang and Wang (1978) did a conodont biostrati- from the Middle Devonian (Givetian), the Guangxi block was graphic work on the section only for the ammonoid beds. On the fragmented and subsided in the context of a progressive transten- basis of these previous records, Hou (1988) concluded the bra- sional tectonic movement of South China block, resulted in a chiopod (he used Eoperegrinella as the genus name) represents transtensional (strike-slip) rift basin domain in the Late Devo- a monotonous brachiopod community that lived in relatively nian (Chen et al., 2001b). Carbonate platforms (or shelf in deep-water pelagic setting in Guizhou and Guangxi and occurred the Early Devonian) developed on the paleohighs were com- within the ammonoid Clymenia Zone (late Famennian) strati- monly bounded by curvilinearly narrow intraplatform basins graphically, as those discovered in southern Ural, Poland, North (or troughs) extending locally for several hundreds of kilome- Africa, and North America. However, such conclusion lacks ters. Such specific platform-basin configuration was interpreted detailed biostratigraphic support. as a result of the major NNE–SSW-trending, sinistral strike- In this paper, we report four newly found localities with slip faulting along the deep-seated basement zones, inducing a occurrence of Dzieduszyckia and present a preliminary result series of secondary fault zones (Chen et al., 2001a, 2001b, 2006; of the conodont biostratigraphic work on these sections. Fur- Fig. 1). The Upper Devonian on the offshore carbonate platform thermore, we give a preliminary report on the morphological setting consists mainly of massive algal, bioclastic, and oolitic variation of the brachiopods on the basis of new collections from limestone (Rongxian Formation), whereas in the intraplatform the studied sections. The detailed systematic paleontological basin setting, it is composed of either thin to medium bedded Please cite this article in press as: Nie, T., et al., Age and distribution of the Late Devonian brachiopod genus Dzieduszyckia Siemiradzki, 1909 in southern China. Palaeoworld (2016), http://dx.doi.org/10.1016/j.palwor.2016.03.005 +Model PALWOR-358; No. of Pages 16 ARTICLE IN PRESS T. Nie et al. / Palaeoworld xxx (2016) xxx–xxx 3 limestone intercalated with cherty bands (Gubi Formation) or clarki Ziegler, Pa. subperlobata Branson et Mehl, Pa. delicatula siliceous rock (Liujiang Formation) in the lower part (mainly delicatula Branson et Mehl, Pa. minuta minuta Branson et Mehl, Frasnian) and banded and nodular limestone (Wuzhishan For- Pa. perlobata perlobata Ulrich et Bassler, Pa. regularis Cooper, mation, Famennian) in the upper part. Pa. sandbergi Ji et Ziegler, Pa. tenuipunctata Sannemann, and Three of the four newly discovered localities with occurrence Pa. werneri Ji et Ziegler with a few primitive Pa. quadrantin- of Dzieduszyckia (Fig. 1), including the Changtang, Duli and odosalobata Sannemann in samples dz5 and dz6, which are Dazhai sections, are situated in the border area between Dushan characteristics of the Upper triangularis Zone (Fig.