Reply to the comment on “Mudflat/distal fan and shallow lake sedimentation (upper Vallesian–Turolian) in the Tianshui Basin, Central China: Evidence against the late Miocene eolian loess” by A.M. Alonso-Zarza, Z. Zhao, C.H. Song, J.J. Li, J. Zhang, A. Martín-Pérez, R. Martín-García, X.X. Wang, Y. Zhang and M.H. Zhang

Guo's et al. comments on our paper (Z.T. Guo, J.Y, Ge, G.Q. Xiao, Q.Z. Hao, H.B. Wu, T. Zhan, L. Liu, L. Qin, F.M. Zeng, B.Y. Yuan, Comment on “Mudflat/distal fan and shallow lake sedimentation (upper Vallesian–Turolian) in the Tianshui Basin, Central China: Evidence against the late Miocene eolian loess” by A.M. Alonso-Zarza, Z. Zhao, C.H. Song, J.J. Li, J. Zhang, A. Martín-Pérez, R. Martín-García, X.X. Wang, Y. Zhang and M.H. Zhang [Sedimentary Geology 222 (2009) 42–51], Sedimentary Geology, 2010-this issue) mostly stress their previous data and their model of configuration and evolution of the study area; it is not a real discussion of the sedimentological features we describe. In this reply we will discuss some of the key features of the basin configuration, correlations and sedimentology of the Tinshui basin. Our work has followed the common procedures used in stratigraphy and sedimentology and so we can confirm our interpretation on basin configuration and correlations. In all cases we have taken into account previous papers, including those of Guo's group. In addition the sedimentological model we proposed is new due to the lack of previous sedimentological studies, including facies analysis and petrography, in the studied area. Our model of a continental alluvial-lacustrine basin fits well with other well-known examples over the world and explains clearly the lateral facies transitions across the basin. It is not the aim of this reply to discuss all the previous papers by Guo's group, but to reply to their main comments on our paper. © 201

A systematic revision of the Ordovician plectambonitoidean brachiopods Chonetoidea and Sericoidea

The revised Treatise on Invertebrate Paleontology, part H: Brachiopoda regards Chonetoidea Jones and Sericoidea Lindström synonymic, on the basis of characters that were considered common to both genera (e.g. ornament type, number of septules). However, some features (e.g. number of septules) discriminate specimens at species level, rather than at generic level as previously thought. Other morphological features, never taken into account or described before, e.g. the position of the ventral diductor scars or the presence of a pair of septules developed anterolaterally to the socket ridges (named praeculmen septules) in Chonetoidea solely, permit a confident separation of the two genera. The ornament is not useful for diagnosing the genera. A review of all species belonging to each genus is made in light of the emended diagnoses of both Chonetoidea and Sericoidea. Based on the internal morphologies of their lophophoral supporting structures and on sedimentological data, Chonetoidea and Sericoidea are interpreted as living in different bathymetric conditions. Chonetoidea was adapted to a more dynamic environment, with higher nutrient levels. Sericoidea needed a wider area for trapping food, in an environment (open water) with three to six times less nutrients than mid to inner shelf environments. The palaeogeographic and stratigraphic distributions of Chonetoidea and Sericoidea indicate the progressive disappearance of Sericoidea and adaptative radiation of Chonetoidea in a palaeoworld where epicontinental seas were shallowing, prior to the end of Ordovician glaciation events which coincided with the extinction of Chonetoidea