Amphibian Biostratigraphy of the European Permo-Carboniferous
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See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/249551833 Amphibian biostratigraphy of the European Permo-Carboniferous Article in Geological Society London Special Publications · January 2006 DOI: 10.1144/GSL.SP.2006.265.01.09 CITATIONS READS 35 45 2 authors: Ralf Werneburg Joerg W. Schneider Naturhistorisches Museum Schl… Technische Universität Bergaka… 65 PUBLICATIONS 504 CITATIONS 287 PUBLICATIONS 2,395 CITATIONS SEE PROFILE SEE PROFILE Some of the authors of this publication are also working on these related projects: Dynamics of Pennsylvanian basin margin to upland environments - a case study from Stephanian fluvial deposits of the Kyffhäuser Mountains (Saale basin, Central Germany) View project Analysis of an Early Permian forest ecosystem preserved in situ by volcanism View project All content following this page was uploaded by Ralf Werneburg on 27 March 2016. The user has requested enhancement of the downloaded file. Amphibian biostratigraphy of the European Permo-Carboniferous RALF WERNEBURG1 & JOERG W. SCHNEIDER2 1Naturhistorisches Museum Schloss Bertholdsburg, Burgstrasse 6, D-98553 Schleusingen, Germany (e-mail: [email protected]) 2TU Bergakademie Freiberg, Cottastrasse 2, D-09596 Freiberg, Germany (e-mail: [email protected]) Abstract: A revised amphibian zonation for the European Pennsylvanian and Cisuralian (Upper Carboniferous to Lower Permian) with nine amphibian zones is presented. The index fossils belong to species-chronoclines with two or three closely related species. The time resolution of these amphibian zones is about 1.5–3.0 Ma. Biostratigraphical correlations with amphibian zones are applicable to 16 basins in the Czech Republic, Poland, France, Italy and Germany. The biostratigraphical potential of other tetrapods is discussed. Tetrapod biostratigraphy or biochronology of ideal index fossils for biostratigraphy. They the non-marine Permian and Carboniferous is are common and have a wide distribution an important and difficult task for palaeo- in space, but a narrow temporal range. Thou- herpetologists. Most of the tetrapod zonations sands of specimens are known of the branchio- for the Permian are reviewed by Lucas (1998, saurs Apateon dracyiensis (Fig. 1a, b), Apateon 2004). They were developed in North America flagrifer and Apateon pedestris, the discosau- for the Upper Carboniferous (Pennsylvanian) riscid Discosauriscus austriacus, as well as and Lower Permian (Cisuralian) as well as in hundreds of individuals of the branchiosaurs South Africa, Russia and China for the Middle Melanerpeton sembachense, M. tenerum and and Upper Permian (Guadalupian, Lopingian). Schoenfelderpeton prescheri. In the European In Europe, tetrapod biostratigraphy was Permo-Carboniferous, up to four genera are established for the Upper Carboniferous and now known with nearly 20 species and subspecies Permian with tetrapod footprints and amphi- of the Branchiosauridae, four genera with 10 bians. Tetrapod footprint zonations for several species of the Micromelerpetontidae and two basins in Europe were developed by Haubold genera with three species of the Discosauriscidae. (1980, 1984, 2000), Holub & Kozur (1981), Boy At least 10 species of these three families are & Fichter (1982, 1988), Gand & Haubold (1988) widespread and known from two or more basins and Kozur (1989). The general problem of tetra- in Europe. pod footprint biostratigraphy is that the tetrapod The history of research of these three amphi- ichnospecies normally correspond to families or, bian families spans as much as 130 years. in the best case, only genera in the osteological Depending on the facies architectures and the system. Therefore, tetrapod ichnospecies reflect degree of investigations, branchiosaurs can show larger steps in tetrapod phylogeny and conse- a high frequency of occurrences in vertical quently only represent longer time intervals sections. In the profile of the Thuringian Forest (Lucas 1998, 2002). Basin, for example, about 11 successive levels Biostratigraphical zonations using osteologi- with branchiosaurs are known, covering a time cal species of aquatic or semi-aquatic amphibians span from the Gzhelian up into Sakmarian, that were presented by Boy (1987) and Werneburg is, 12 Ma (Werneburg 1989a, 2001a). The family (1989a, b, 1996). These amphibians belong to Branchiosauridae exhibits a high rate of specia- the dissorophoid Branchiosauridae and Micro- tion with many short-lived species (but also with melerpetontidae, to the stem-stereospondyl some long-lived species, such as Apateon flagrifer Archegosauriformes and to the seymouriamorph or A. pedestris). Discosauriscidae. The taxonomic concept of the Branchiosauri- dae and Micromelerpetontidae (Boy 1972 ff.; Basics of amphibian zonation Werneburg 1986a ff.) as well as of the Disco- sauriscidae (Klembara & Meszároš 1992 ff.) has The newt-like families Branchiosauridae, been extensively discussed, and a relatively wide Micromelerpetontidae and Discosauriscidae are consensus has been achieved. It is necessary to From: LUCAS, S. G., CASSINIS, G. & SCHNEIDER, J. W. (eds) 2006. Non-Marine Permian Biostratigraphy and Biochronology. Geological Society, London, Special Publications, 265, 201–215. 0305-8719/06/$15.00 © The Geological Society of London. 202 R. WERNEBURG & J. W. SCHNEIDER Fig. 1(a) & (b) The branchiosaur Apateon dracyiensis from the Lower Goldlauter Formation (Lower Rotliegend, Asselian) of Cabarz/Tabarz in the Thuringian Forest Basin (skull length about 8mm). AMPHIBIAN BIOSTRATIGRAPHY 203 Fig. 1(b). 204 R. WERNEBURG & J. W. SCHNEIDER present some short remarks on the grammati- of species is determined by their more or less cally correct use of the Apateon species names. well-known First (FAD) and Last Appearance For a long time, the grammatical gender of the Dates (LAD). However, compared to marine genus was not clear. The type species is Apateon sections, the patchy, discontinuous fossil record pedestris Meyer, 1844. Werneburg (1988a ff.) in continental deposits prevents the exact deter- has used the feminine gender for several species mination of FADs and LADs. So, it is easier of Apateon (e.g. A. flagrifera, A. caduca and A. to apply the First Occurrence Date (FOD; lowest umbrosa). But, now it is clear that the genus occurrence) and the Last Occurrence Date Apateon has a masculine gender. Consequently, (LOD; highest occurrence) for definition of the the species of Apateon have the following amphibian zones. Nevertheless, the increasing amended endings: Apateon pedestris, A. caducus, discoveries of amphibian sites (e.g. Ronchi & A. flagrifer, A. kontheri, A. dracyiensis, A. Tintori 1997; Werneburg 2003) and the cross- intermedius and A. umbrosus. check with the insect zones (Schneider 1982; The palaeoecology of all three families is Schneider & Werneburg 1993) as well as isotopic well known (e.g. Boy 2003; Boy & Sues 2000; ages (Lützner et al. 2003) are leading to increased Werneburg 2001b, 2002). Nearly all of their improvements of the amphibian biostratigraphy. members are aquatic and neotenic. They lived in Most of the fossil taxa are a mixture of lakes of different sizes, and they are also known biospecies and chronospecies. In the case of from grey and red facies deposits. It was possible branchiosaurs we have some well-known com- to distinguish two ecomorphotypes, the pond- munities of one lake with three different species, type and the stream-type, which are based on such as, Apateon flagrifer, A. kontheri and well-known forms based on extant larval sala- Melanerpeton eisfeldi from the Gottlob Lake manders (Werneburg 2002). The best fossil in the Thuringian Forest Basin of Germany record is known from lacustrine deposits, but (Werneburg 1986b, 1988a). These are real fine clastic intercalations in fluvial coarse clastics biospecies with clear-cut features. Many of the could also contain remains of those amphibians. other branchiosaurs may be chronospecies. Both The phylogeny, especially of the branchio- kinds of species are used in the biostratigraphical saurs, is a more difficult problem. This amphi- concept of species chronoclines. bian family was able to adapt to the changing palaeogeographical and palaeoecological condi- Amphibian zonation tions in the European variscids through fast radiation and paedomorphosis (neoteny). The The first amphibian biostratigraphy was estab- result is a complicated mosaic-pattern in their lished by Boy (1987) for the Lower Permian evolution. It is difficult to find clear-cut, uniquely Rotliegend of the Saar–Nahe Basin. It is an derived characters for each species. A first draft assemblage zonation based on branchiosaurid of a phylogeny (Werneburg 1989a, b) was based and archegosauriform species known from this on a detailed list of constitutive and diagnostic basin only. Boy (1987) proposed an additional features as a basis for the definition for each biostratigraphic zonation for the middle taxon (Werneburg 1989a). Meanwhile, with European Rotliegend based on branchiosaurid more studies, this concept has been confirmed: relationship-groups: for discosauriscids (Klembara 1997), Microme- • Zone of Apateon pusillus group (with uncer- lerpeton (Boy 1995, 2000a, b) and Melanerpeton tain relationship) (Werneburg 1991). • Zone of Apateon caducus group (with A. The basic concepts of amphibian biostra- flagrifer) tigraphy presented here are lineages of two or • Zone of Apateon pedestris (oldest one from three chronologically successive species. This is