Micromeryx? eiselei—A new moschid species from Steinheim am Albuch, Germany, and the first comprehensive description of moschid cranial material from the Miocene of Central Europe

Abstract

Moschids are enigmatic pecoran ruminants whose phylogeny is still not fully understood. So far we know only little of the family’s early evolutionary history and the origin of the modern genus, Moschus. Here we present a comprehensive description of cranial material, including the ear region and the dentition, of fossil moschid material from the Middle Miocene locality Steinheim am Albuch (13.5 Ma; Germany). This study provides the first exhaustive dataset for the cranial osteology of Micromeryx flourensianus, the most likely oldest true moschid. It furthermore reveals the presence of a second, so far undescribed moschid species, we here name Micromeryx? eiselei, in the abundant material from the locality. The two taxa can be clearly distinguished by characters of the skull, the ear region, the dentition, as well as by size. This evidences the sympatric occurrence of two moschid species in the locality Steinheim am Albuch.

On the oldest Mongolian moschids (Mammalia, Ruminantia) and the early moschid evolution

“…First of all, the relatively high crown of the tooth is neither present in early Cervidae, from the early and middle Miocene, nor in Lagomerycidae, (e.g., Azanza and Ginsburg, 1997;Rössner, 2010). Moreover, the split of anterior stylid and anterior conid, the closure of the anterior valley with participation of an anterolingual cristid, an elongated mesolingual conid lacking a strong lingual rib and fusing with an oblique cristid obliqua at the posterior tip of the posterolingual cristid, as well as an open posterior valley in the p4 is characteristic for the Moschidae among all Oligocene to middle Miocene Pecora (e.g., Sánchez and Morales, 2008;Sánchez et al, 2010Sánchez et al, , 2011Aiglstorfer and Costeur, 2013;Aiglstorfer et al, 2017; and see Mennecart, 2012, 2015 for late Oligocene to early Miocene ruminants; Azanza and Ginsburg, 1997;Ginsburg and Chevrier, 2003;Rössner, 2010 for Lagomerycidae;van der Made, 2012;Köhler, 1987;Suraprasit et al, 2013 for middle Miocene Bovidae from Eurasia). In the North American "Blastomerycidae" there is a slight tendency to close the anterior valley in the p4 as well (personal observation on the material housed at the AMNH).…”

“…During their evolutionary history, moschids were far more diverse and widespread over Eurasia (e.g., Morales, 2006, 2008;Sánchez et al 2009Sánchez et al , 2010Sánchez et al , 2011Wang et al, 2015;Aiglstorfer et al, 2017Aiglstorfer et al, , 2018. However, only little is known on the origin and early evolution of this family, especially in Asia.…”

“…The determination of the ruminant remains defined as Micromeryx from the early Miocene locality Damiao DM16 (Wang et al, 2015) by Zhang et al (2011) has been questioned due to the fragmentary state of the specimens (Wang et al, 2015). No less than six species of Micromeryx and three species of Hispanomeryx are known in Western and Central Europe (Thenius, 1950;Morales et al, 1981;Azanza, 1986;Vislobokova, 2007;Sánchez and Morales, 2008;Sánchez et al, 2009;Sánchez et al, 2010;Liu and Groves, 2016;Aiglstorfer et al, 2017). In contrast, only a few remains of Micromeryx and Hispanomeryx are currently known from Asia, comprising one described Hispanomeryx species: Hispanomeryx abdrewsi from the Chinese Wolf Camp, Tunggur Formation (Sánchez et al, 2011).…”

Who killed Micromeryx flourensianus ? A case study of taphonomy and predation on ruminants in the middle Miocene of France

“…There is only one extant moschid genus, found in mountainous regions of Asia and comprising six endangered and one vulnerable species (IUCN, 2018). During the Miocene, the family was far more widespread and was a common faunal element in Eurasia (Vislobokova 2007;S anchez & Morales 2008;S anchez et al 2009, 2010Vislobokova & Lavrov 2009;Aiglstorfer & Costeur 2013;Aiglstorfer et al 2014Aiglstorfer et al , 2017Aiglstorfer et al , 2018Wang et al 2015). Micromeryx flourensianus, for which Sansan is the type locality, is possibly the oldest true moschid species.…”

Revision of the plant assemblage of Steinheim am Albuch (Baden- Württemberg, Germany, middle Miocene, reference locality of Mammal Neogene Zone MN 7)

“…intermedius, Pseudaelurus quadridentatus, Pseudaelurus lorteti, Sansanosmilus jourdani, Semigenetta sansaniensis), Perissodactyla (Anchitherium aurelianense, Alicornops simorrense, Lartetotherium sansaniense, Dicerorhinus steinheimensis, Metaschizotherium fraasi), Proboscidea (Gomphotherium steinheimense), and Artiodactyla (Listriodon splendens, Conohyus simorrensis, Albanohyus pygmaeus, Micromeryx flourensianus, Euprox furcatus, Heteroprox larteti, Palaeomeryx eminens, Dorcatherium crassum) (Mein 1989, modified after Heizmann in Heizmann & Reiff 2002. Most recently, an additional moschid species, ?Micromeryx eiselei, was recognised within the Steinheim fauna (Aiglstorfer et al 2017).…”