Pala¨ontol Z (2016) 90:63–99 DOI 10.1007/s12542-015-0277-1 RESEARCH PAPER Terrestrial and lacustrine gastropods from the Priabonian (upper Eocene) of the Sultanate of Oman 1 1 2 3 Mathias Harzhauser • Thomas A. Neubauer • Dietrich Kadolsky • Martin Pickford • Hartmut Nordsieck4 Received: 17 January 2015 / Accepted: 15 September 2015 / Published online: 29 October 2015 Ó The Author(s) 2015. This article is published with open access at Springerlink.com Abstract Terrestrial and aquatic gastropods from the sparse non-marine fossil record of the Eocene in the Tethys upper Eocene (Priabonian) Zalumah Formation in the region. The occurrence of the genera Lanistes, Pila, and Salalah region of the Sultanate of Oman are described. The Gulella along with some pomatiids, probably related to assemblages reflect the composition of the continental extant genera, suggests that the modern African–Arabian mollusc fauna of the Palaeogene of Arabia, which, at that continental faunas can be partly traced back to Eocene time, formed parts of the southeastern Tethys coast. Sev- times and reflect very old autochthonous developments. In eral similarities with European faunas are observed at the contrast, the diverse Vidaliellidae went extinct, and the family level, but are rarer at the genus level. These simi- morphologically comparable Neogene Achatinidae may larities point to an Eocene (Priabonian) rather than to a have occupied the equivalent niches in extant environ- Rupelian age, although the latter correlation cannot be ments. Carnevalea Harzhauser and Neubauer nov. gen., entirely excluded. At the species level, the Omani assem- Arabiella Kadolsky, Harzhauser and Neubauer nov. gen., blages lack any relations to coeval faunas. This suggests Pyrgulella Harzhauser, Kadolsky and Neubauer nov. gen., the possible presence of a distinct biogeographic province Salalahia Kadolsky, Harzhauser and Neubauer nov. gen., during the Palaeogene or may simply reflect the extremely Omanitopsis Harzhauser and Neubauer nov. gen., Arabi- colaria Harzhauser and Neubauer nov. gen., Pacaudiella Harzhauser and Neubauer nov. gen., Goniodomulus Harz- With a contribution on the Clausilioidea by Hartmut Nordsieck. hauser and Neubauer nov. gen., Eoquickia Harzhauser and Neubauer nov. gen., Omanillya H. Nordsieck nov. gen. and & Mathias Harzhauser Omanifera [email protected] H. Nordsieck nov. gen. are introduced as new genera. Pila neuberti Harzhauser and Neubauer nov. sp., Thomas A. Neubauer Arabiella arabica Kadolsky, Harzhauser and Neubauer [email protected] nov. sp., Pyrgulella parva Harzhauser, Kadolsky and Dietrich Kadolsky Neubauer nov. sp., Salalahia thaytinitiensis Kadolsky, [email protected] Harzhauser and Neubauer nov. sp., Omanitopsis van- Martin Pickford dammei Harzhauser and Neubauer nov. sp., Procyclotopsis [email protected] eocenica Harzhauser and Neubauer nov. sp., Palaeocy- Hartmut Nordsieck clotus kuehschelmi Harzhauser and Neubauer nov. sp., [email protected] Arabicolaria arabica Harzhauser and Neubauer nov. sp., 1 Natural History Museum Vienna, Burgring 7, 1010 Vienna, Pacaudiella omanica Harzhauser and Neubauer nov. sp., Austria Pacaudiella flammulata Harzhauser and Neubauer nov. sp., 2 66 Heathhurst Road, Sanderstead CR2 0BA, Surrey, UK Goniodomulus solaniformis Harzhauser and Neubauer nov. 3 Sorbonne Universite´s-CR2P, MNHN, CNRS, UPMC-Paris sp., Cerastus hyznyi Harzhauser and Neubauer nov. sp., VI, 8, rue Buffon, 75005 Paris, France Omanillya lunellifera H. Nordsieck nov. sp., Omanillya 4 Senckenberg Forschungsinstitut Frankfurt; Malakologie, costellata H. Nordsieck nov. sp., and Omanifera euclista Senckenberganlage 25, 60325 Frankfurt Am Main, Germany H. Nordsieck nov. sp. are described as new species. 123 64 M. Harzhauser et al. Keywords Mollusca Á Arabian Peninsula Á nov. sp. und Omanifera euclista H. Nordsieck nov. sp. Biogeography Á Paleogene Á Palaeoecology werden als neue Arten beschrieben. Kurzfassung Terrestrische und aquatische Gastropoden Schlu¨sselwo¨rter Gastropoda Á Sultanat Oman Á aus der obereoza¨nen (Priabonium) Zalumah-Formation in Biogeographie Á Eoza¨n Á Pala¨oo¨kologie der Salalah-Region des Sultanats Oman werden beschrieben. Die Vergesellschaftungen reflektieren die Zusammensetzung der kontinentalen Molluskenfaunen des Introduction Pala¨ogens Arabiens, das zu dieser Zeit die su¨do¨stliche Ku¨ste der Tethys formte. A¨ hnlichkeiten mit europa¨ischen Fossils from Palaeogene strata of the Zalumah Formation Faunen lassen sich auf Familien- und selten auch auf cropping out in Dhofar Province, Sultanate of Oman, have Gattungsniveau nachweisen. Diese U¨ bereinstimmungen been described in a number of publications (Thomas et al. sprechen eher fu¨r ein eoza¨nes Alter (Priabonium) als fu¨r 1988, 1989, 1991, 1992, 1999; Roger et al. 1993; eine Einstufung ins Rupelium, obwohl letzteres nicht Gheerbrant et al. 1993, 1995; Pickford and Thomas 1994; vo¨llig ausgeschlossen werden kann. Auf Artniveau fehlen Neubert and Van Damme 2012; Pickford et al. 1994, Bezu¨ge zu gleichalten Faunen. Das ko¨nnte auf eine dis- 2014). This is the third paper devoted to the Eocene (or krete pala¨ogene Bioprovinz hinweisen oder einfach aus lowermost Oligocene) continental mollusc fauna of the dem extrem du¨rftigen nicht-marinen Fossilbefund des Zalumah Formation in the Salalah region. Apart from tethyalen Eoza¨ns resultieren. Das Vorkommen von Gattun- some remarks in geological reports by Roger et al. gen wie Lanistes, Pila und Gulella, gemeinsam mit (1989), Neubert and Van Damme (2012) were the first to einigen Pomatiiden, die mit rezenten Gattungen verwandt describe a small gastropod assemblage from Haluf and sein du¨rften, zeigt, dass die Wurzeln der modernen afri- Thaytiniti. These authors already recognised the assem- kanisch-arabischen kontinentalen Molluskenfauna zumin- blage as completely new and introduced several new dest teilweise bis ins Eoza¨n zuru¨ckreichen. Im Gegensatz species names for some of the better preserved specimens. dazu starben die artenreichen Vidaliellidae aus, und die Simultaneously, Pickford et al. (2014) focussed on the morphologisch a¨hnlichen Achatinidae du¨rften ihre o¨kolo- assemblages from Taqah in the Wadi Darbat and provided gischen Nischen im Neogen u¨bernommen haben. Carne- a first revision of the fauna, proposing several new valea Harzhauser und Neubauer nov. gen., Arabiella combinations. Both teams focussed on the relations of the Kadolsky, Harzhauser und Neubauer nov. gen., Pyrgulella Omani taxa to modern Afro-Arabian genera and were Harzhauser, Kadolsky und Neubauer nov. gen., Salalahia limited in their identifications by the rather poor preser- Kadolsky, Harzhauser und Neubauer nov. gen., Omani- vation of their material. An intense sampling campaign by topsis Harzhauser und Neubauer nov. gen., Arabicolaria the Franco-Omani Palaeontology Mission resulted in new, Harzhauser und Neubauer nov. gen., Pacaudiella Harz- voluminous and much better preserved material from the hauser und Neubauer nov. gen., Goniodomulus Harzhau- same sections. Therefore, some of the previous determi- ser und Neubauer nov. gen., Eoquickia Harzhauser und nations can be revised and new data on morphological Neubauer nov. gen., Omanillya H. Nordsieck nov. gen. features can be added to species described by Neubert and und Omanifera H. Nordsieck nov. gen. Werden als neue Van Damme (2012). Moreover, this newly collected Gattungen eingefu¨hrt. Pila neuberti Harzhauser und material contains at least 20 species which were not Neubauer nov. sp., Arabiella arabica Kadolsky, Harz- present in the samples available to Neubert and Van hauser und Neubauer nov. sp., Pyrgulella parva Harz- Damme (2012) in their pioneer paper. hauser, Kadolsky und Neubauer nov. sp., Salalahia thaytinitiensis Kadolsky, Harzhauser und Neubauer nov. sp., Omanitopsis vandammei Harzhauser und Neubauer Localities and geological setting nov. sp., Procyclotopsis eocenica Harzhauser und Neu- bauer nov. sp., Palaeocyclotus kuehschelmi Harzhauser Detailed descriptions of the geological setting are given by und Neubauer nov. sp., Arabicolaria arabica Harzhauser Roger et al. (1989, 1993) and Pickford et al. (2014), who und Neubauer nov. sp., Pacaudiella omanica Harzhauser also provide an overview on the papers dealing with the und Neubauer nov. sp., Pacaudiella flammulata Harz- famous vertebrate faunas of the region. Sampling took hauser und Neubauer nov. sp., Goniodomulus solaniformis place in January 2013 at the three localities Taqah (TQ), Harzhauser und Neubauer nov. sp., Cerastus hyznyi Thaytiniti (TN), and Haluf (HF) (Fig. 1), where fossilif- Harzhauser und Neubauer nov. sp., Omanillya lunellifera erous, biomicritic white to beige freshwater limestones of H. Nordsieck nov. sp., Omanillya costellata H. Nordsieck the Zalumah Formation crop out close to sea level in the 123 Terrestrial and lacustrine gastropods from the Priabonian (upper Eocene) of the Sultanate of… 65 Fig. 1 Geographic position of the investigated sections in the Dhofar region in the southwestern part of the Sultanate of Oman Wadi Darbat and at altitudes of over 700 m at Thaytiniti Table 1 Geographic positions and and altitudes of the samples, with and the Haluf Graben. A detailed sedimentological sample code numbers description of the sections, however, has not been pub- Locality Latitude Longitude Altitude Code lished so far. (m) The age of the Zalumah Formation is given as Priabo- Taqah 2 17°02043.500N54°26051.100E 25 TQ2 nian to early Rupelian by Pickford et al. (2014), but 0 00 0 00 unequivocal