Palaeogeography, Palaeoclimatology, Palaeoecology 461 (2016) 224–236 Contents lists available at ScienceDirect Palaeogeography, Palaeoclimatology, Palaeoecology journal homepage: www.elsevier.com/locate/palaeo Paleobiogeography of Early/Middle Miocene terrestrial gastropods in Central Europe: An approach using similarity indices Olaf Höltke a,⁎, Rodrigo B. Salvador a,b,MichaelW.Rassera a Staatliches Museum für Naturkunde Stuttgart, Stuttgart, Germany b Mathematisch-Naturwissenschaftliche Fakultät, Eberhard Karls Universität Tübingen, Tübingen, Germany article info abstract Article history: Terrestrial gastropods are a common faunal element in continental Miocene fossil Lagerstätten of Europe. Received 18 February 2016 Although having lived during a time span that includes the Miocene Climatic Optimum and the devastating Received in revised form 11 August 2016 Ries/Steinheim meteorite impacts, the state of knowledge about their faunal composition and geographic distri- Accepted 21 August 2016 bution is surprisingly incomplete. The land snail faunas of 30 different Early and Middle Miocene deposits of Available online 26 August 2016 Central Europe (European Mammal Neogene zones MN 4 to MN 8) were compared using statistical methods (cluster and NMDS analyses, using the Ochiai, Simpson and Kulczynski indices). This includes 300 different Keywords: fi Cluster analysis taxa identi ed so far. Most of the analyzed deposits were part of the Miocene Paratethys and are today located Helicidenmergel in France, SW Germany (Baden-Württemberg state), SE Germany (Bavaria state), Austria, Poland, and Hungary. Ries/Steinheim impacts Cluster analyses resulted in different clusters, the majority of which can be explained by their geographic Silvana Beds situation and/or by their distribution in time (e.g., the consistently recovered Baden-Württemberg and Bavaria Upper Freshwater Molasse clusters and the Bakony Mountains cluster). The remaining clusters cannot be fully explained so far, but some possibilities are explored here. Our results reveal the power of a solid taxonomic framework as a basis for palaeobiogeographic studies. As such, more “basic” palaeontological studies are required to strengthen future analyses. © 2016 Elsevier B.V. All rights reserved. 1. Introduction particular importance, since the “Mid-Miocene Climatic Optimum” (ca. 17–15 Ma; European Mammal Neogene zone MN 5) was the last Continental gastropods, especially those belonging to the Pulmonata, time interval favorable for thermophilous fauna and flora in Europe are a crucial faunal element in Miocene continental deposits. Despite and a time of increased seasonality (Zachos et al., 2001; Böhme et al., their abundance in the European fossil record, however, only few at- 2011). We compare the land snail faunas of thirty distinct localities tempts have been made to study them from a paleobiogeographical from the Middle Miocene of Poland, Hungary, Austria, Germany and point of view. Esu (1999) broadly described the land snail faunal changes France (Fig. 1), searching for similarities and differences. These localities throughout the Neogene, but only in relation to climatic changes and in a were chosen according to their state of knowledge (and eventually the more descriptive and qualitative manner. Stworzewicz (1993) also car- authors' ongoing works). After an overall statistical analysis clustering ried on a qualitative analysis, focusing only on the terrestrial gastropods these localities in groups, we offer more detailed explanations of the lo- of Poland. Finally, Harzhauser and Mandic (2008) analyzed the faunal di- calities and the relationship between them. versity of freshwater gastropods of Neogene lake systems in Central and Southern Europe, describing also the interrelationships of these lakes. 2. Material and methods Following a similar course as these previous authors, we aim to fill some gaps in the paleobiogeographical knowledge of terrestrial gastro- Information on each fossil deposit and its respective land snail fauna pods and present a study of the Miocene land snail fauna of Central is widely scattered throughout the literature. Unfortunately, several of Europe. We focus on deposits that are sufficiently known and studied. these localities were never systematically examined and species lists This means basically the Middle Miocene outcrops, in special the are rarely present; or, when present, not entirely reliable. Apart from stratigraphic group known as the Upper Freshwater Molasse (“Obere some very recent works, the literature is mostly dated from the end of Süßwassermolasse”, in German; abbreviated OSM). This age is of the 19th century or beginning of the 20th century (mainly Wenz, 1923), especially for the OSM. ⁎ Corresponding author. Furthermore, for a locality to be chosen for the present analysis, it E-mail address: [email protected] (O. Höltke). should count with at least eight different terrestrial gastropod species. http://dx.doi.org/10.1016/j.palaeo.2016.08.027 0031-0182/© 2016 Elsevier B.V. All rights reserved. O. Höltke et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 461 (2016) 224–236 225 Fig. 1. Stratigraphy and localities. Mammal Neogene (MN) zones after Kälin and Kempf (2009). Map modified after Rasser and Harzhauser (2008). This was deemed a good number for the biogeographical analysis and The generic assignment of many species has changed often over the this choice implies that most known localities were left out, since they past century and sometimes there are concurrent distinct opinions usually have just a few records of the most common species. There are about this matter. Conveniently, our statistical methodology only com- two exceptions to this rule: Amstetten-Stubersheim and Harthausen pares taxa at the species level, so distinct generic placements do not auf der Scher, both in Germany (Fig. 1). Despite having only five species interfere. each, these localities were included because they are the best represen- tatives in number of species of the Helicidenmergel stratigraphic unit 2.2. Stratigraphy (see below). Data on stratigraphy and age of the Middle Miocene localities 2.1. Taxonomy used here were also acquired from the literature (Table 1). The age of the localities range from the European Mammal Neogene zones The systematic classification used here follows the most recent MN 4–5toMN7–8, spanning the entire Middle Miocene. During works for each locality (as listed on Table 1), with eventual updates this period, two meteorite impacts have occurred in southern of posterior taxonomic works. On a few cases, literature data was Germany, the so-called Ries impact (ca. 14.7 Ma) and the less- complemented with material from the collection of the Staatliches known Steinheim event (Buchner et al., 2013; Buchner and Schmieder, Museum für Naturkunde Stuttgart (SMNS; Stuttgart, Germany). 2013). 226 O. Höltke et al. / Palaeogeography, Palaeoclimatology, Palaeoecology 461 (2016) 224–236 Table 1 List of all localities used for the present analyses, with data on their stratigraphy and age, total number of land snail species, and references for the species list. The full species list of each locality can be found in the Appendix A. Locality Country Stratigraphy/age Nr. species References Adelschlag-Fasanierie Germany OSM/MN 5 8 Salvador et al. (2016) Altheim (near Ehingen) Germany OSM (Silvana Beds)/MN 5 11 Wenz (1923), Gottschick (1928), Esu, 1999 Amstetten-Stubersheim Germany Helicidenmegel/MN 4–55 Jooss (1923), Schweigert (1996), Berger et al. (2005) Bakony Mts C Hungary Lower Badenian 18 Kókay (2006) Bakony Mts D Hungary Middle Badenian 13 Kókay (2006) Bakony Mts E Hungary Upper Badenian 49 Kókay (2006) Bakony Mts F Hungary Sarmatian 79 Kókay (2006) Bechingen Germany OSM (Silvana Beds)/MN 5 15 Salvador and Rasser (2016a) Bełchatów Poland MN 5–631Stworzewicz (1995, 1999a, 1999b), Stworzewicz and Soltys (1996), Stworzewicz and Prisyazhnyuk (2006) Gratkorn Basin Austria MN 7–813Harzhauser et al. (2008) Gündlkofen Germany OSM/MN 5–68Gall (1980), Salvador (2014) Harthausen auf der Scheer Germany Helicidenmegel/MN 4–55 Jooss (1923), Schweigert (1996), Berger et al. (2005) Oggenhausen Germany OSM (Silvana Beds)/MN 5 9 Berz and Jooss (1927), Böttcher et al. (2009), Salvador and Rasser (2016b) Hohenmemmingen Germany OSM (Silvana Beds)/MN 5 22 Gottschick and Wenz, 1916; Esu, 1999; SMNS collection material Korneuburg Basin Austria MN 5 20 Daxner-Höck (2001), Binder (2002, 2003) Lake Rein Austria MN 5 30 Harzhauser et al. (2014) Mátraszőlős Hungary MN 7 15 Hír and Kókay (2004) Mörsingen Germany OSM (Silvana Beds)/MN 5 37 Gottschick and Wenz (1916), Wenz (1923), Esu (1999), Höltke and Rasser (in preparation) Opole Poland MN 7 48 Andreae (1902, 1904), Wenz (1923), Nordsieck (1981), Ginsburg (1999) Pfänder Austria OSM (Silvana Beds)/MN 5 25 Jooss (1910), Wenz (1933, 1935), Esu (1999) Randeck Maar Germany OSM (Silvana Beds)/MN 5 20 Salvador et al. (2015) Riedensheim Germany OSM/MN 5 16 Salvador et al. (2016) Sandelzhausen Germany OSM/MN 5 14 Salvador (2013a, 2013b, 2015), Salvador and Rasser (2014) Sansan France MN 6 23 Wenz (1923), Fischer (2000) Steinheim Germany MN 7 52 Gottschick and Wenz (1919), Gottschick (1919, 1920a, 1920b, 1920c, 1921), Wenz (1922, 1923), Finger (1998), Ginsburg (1999), Höltke and Rasser (submitted) Stoffelberg (near Ehingen) Germany OSM (Silvana Beds)/MN 5 16 Wenz (1923), Esu (1999) Undorf Germany OSM (Silvana Beds)/MN 5 33 Clessin (1910-1911), Fejfar (1999) Zwiefalten Germany OSM (Silvana Beds)/MN 5 10 SMNS collection material