Description: The Baelen mud mounds in eastern Belgium represent a local member of the mid-Famennian Souverain-Pré Formation (an important carbonate interval within the Condroz Sandstone Group). The lower part of this member contains silty bioclastic wackestones and packstones that are particularly rich in the problematical protists Serrisinella and Dreesenulella . Plurilocular foraminifera ( Septabrunsiina and Baelenia ) and rare solitary rugose corals ( Neaxon ? sp.) occur within crinoidal grainstones (tempestites) interfingering with the latter bioclastic wacke-/packstones and with red-stained stromatactoid spiculitic mudstones (carbonate mud mound core facies). Although Serrisinella is quite common in other mid-Famennian limestones of Belgium, Dreesenulella is almost endemic of the Baelen Member. Both genera apparently inhabited the muddy sediment-water interface, constituting meadows probably in zones of intermittently strong bottom currents. The taxonomic similarities between Dreesenulella and Saccamminopsis are discussed, as well as their possible affinities with the Xenophyophora and Kokomiacea. The first stages of the Septabrunsiina – Baelenia foraminiferal lineage are analysed in detail. The taxonomic and palaeoecological positioning of Serrisinella and Dreesenulella adds to the discussion about the palaeobathymetry of the Baelen mud mounds and corroborates sedimentological evidence for their relatively shallow carbonate ramp depositional setting.

Description: The Taatsiin Gol Basin in Mongolia is a key area for understanding the evolution and dispersal of Central Asian mammal faunas during the Oligocene and early Miocene. After two decades of intense fieldwork, the area is extraordinarily well sampled and taxonomically well studied, yielding a large dataset of 19,042 specimens from 60 samples. The specimens represent 176 species-level and 99 genus-level taxa comprising 135 small mammal species and 47 large mammals. A detailed lithostratigraphy and new magnetostratigraphic and radiometric datings provide an excellent frame for these biotic data. Therefore, we test and evaluate the informal biozonation scheme that has been traditionally used for biostratigraphic correlations within the basin. Based on the analysis of the huge dataset, a formalised biostratigraphic scheme is proposed. It comprises the Cricetops dormitor Taxon Range Zone (Rupelian), subdivided into the Allosminthus khandae Taxon Range Subzone and the Huangomys frequens Abundance Subzone, the Amphechinus taatsiingolensis Abundance Zone (early Chattian), the Amphechinus major Taxon Range Zone (late Chattian), subdivided into the Yindirtemys deflexus Abundance Subzone and the Upper Amphechinus major T. R. Z., and the Tachyoryctoides kokonorensis Taxon Range Zone (Aquitanian). In statistical analyses, samples attributed to these biozones form distinct clusters, indicating that each biozone was also characterised by a distinct faunal type.

Description: The most earliest Mississippian rugose corals are post-disaster taxa occurring in a biosphere strongly modified by the crises associated with the Devonian-Carboniferous Boundary. In Western Europe, basal Tournaisian rugose corals belong to the genera Conilophyllum , Hebukophyllum and Kizilia. Conilophyllum and Hebukophyllum are either homeomorphs or close relatives of each other and are likely post-disaster fauna showing wide morphological plasticity but with an unknown origin. Kizilia is a Lazzarus taxon, known also from basal Tournaisian strata of China, that suddenly reappeared at the Devonian-Carboniferous Boundary being related to the mid-Devonian stringophyllids. The deeper basinal facies of Western Europe (Montagne Noire, Rhenish Mts, Thuringia, Upper Franconia) yield mostly small non-dissepimented solitary rugose corals, together with some dissempimented ones, amongst which are mostly long-ranging taxa. In N America, Vesiculophyllum , a genus very similar, and probably related, to Kizilia occurs together with non-dissepimented long-ranging corals. Like most of the basal Tournaisian dissepimented rugose corals, Cystodactylon orbum gen. et sp. nov. and Gudmania darumbalae gen. et sp. nov. from the basal Tournaisian of eastern Australia are interpreted as post-disaster fauna. Their origin is not understood to date and they seemingly left no descent in the Carboniferous. Their stratigraphic range is extremely limited as they so far are known only in small reefs at the base of the lower Tournaisian Gudman Formation in the type area.

Description: The oldest vertebrates are Early Cambrian, cephalized unossified species (craniates) from China. The oldest armoured species (euvertebrates) are Ordovician in age. After Talimaa’s Gap, vertebrates have their first adaptive radiation during the Silurian when jawless species (“ostracoderms”) are dominant and their second radiation during the Devonian when jawed species (gnathostomes), and particularly placoderms (armoured fishes), are dominant. A Lochkovian peak of diversity is registered in various Lower Devonian siliciclastic series all around the Old Red Sandstone Continent and Siberia, for ostracoderms in general, and heterostracan pteraspidomorphs in particular. It occurs at different time slices in the Lochkovian, depending on the localities, and may be followed by another smaller peak in the Pragian. Both events correspond to the rise of the Devonian Nekton Revolution as defined for marine invertebrates. This appears to be the second main biodiversification event in the Palaeozoic, following the Great Ordovician Biodiversification Event or GOBE, when euvertebrates appeared. Taking into account most recent palaeobiological studies on heterostracans that suggest they were microphagous suspension feeders or feeding upon microscopic epiphytes from filamentous algae, the origin of this Great Eodevonian Biodiversification Event (GEBE) of heterostracans is questioned. Both abiotic (sea level, tectonic events, climatic changes—oceanic oxygenation and temperature, continental surface temperature) and biotic (plankton diversity, marine primary productivity, competition with vertebrates and invertebrates, including eurypterids, macroecological turnover) factors are examined. No plausible global evolutionary scenario seems to be presently available.

Description: The Zefreh section in central Iran represents a carbonate ramp succession with a general shallow-marine palaeoenvironment. This section represents most of the Bahram Formation (Givetian to at least Middle falsiovalis Zone) and consists of a very heterogeneous succession of medium- to coarse-grained sandstones, skeletal pack- to grainstones with local biostromes, massive or laminated dolostones, and shales. Microfacies analysis allowed the discrimination of 12 microfacies reflecting supratidal to open marine palaeoenvironments. The shallow-marine environment was investigated using facies analysis and geochemical proxies. Redox conditions in the Zefreh section appear to be primarily oxic and support the facies and sedimentological results. The provenance of the Zefreh sediments using La, Sc, Zr, and Th indicates that they are most likely derived from continental arc volcanics which is consistent with the preliminary tectonic interpretations. Conodonts and brachiopods were used for establishing the biostratigraphical framework. The lack of important zonal index taxa of the widely applied conodont standard zonation requires the application of an alternative shallow-marine conodont zonation. Based on conodont and brachiopod data, the Zefreh section covers sediments ranging from the upper Givetian to lower Frasnian.

Description: The present publication reports new discoveries of Oligocene and early Miocene aplodontid rodents from the Taatsiin Gol area (Valley of Lakes) in Mongolia. The fossil aplodontids recovered in this area are mainly composed of dental remains, some fragmentary jaws plus one partially preserved skull. Aplodontid rodents have been found from the early Oligocene (local biozone A) to the early middle Miocene (local biozone D). Altogether, eight taxa belonging to five genera have been identified in the investigated deposits: Ninamys arboraptus , Ninamys kazimierzi , Promeniscomys cf. sinensis , Prosciurus ? mongoliensis and Prosciurus ? sp. nov. in the early Oligocene; N. arboraptus , Proansomys badamae sp. nov. and Ansomyinae indet. in the late Oligocene; and Ansomys sp.1 in the early Miocene. In addition, although outside of the topic of the present special issue, one additional taxon, Ansomys sp.2, is reported from the ?middle Miocene. The material of aplodontids is usually relatively scarce in Asian localities. For the first time, with a sample size of 81 specimens, the material from Central Mongolia (mainly from the Oligocene) now allows a more accurate description of the morphological and size variability and resolves some systematic problems. The study of these aplodontids reveals that they are more abundant and diverse in the early Oligocene and that the diversity decreases during the late Oligocene and Miocene. One hypothesis, to explain the opposite diversity trend observed previously for sciurids in the same region, is that both Sciuromorpha families might have competed for the same resources from the early Oligocene to the middle Miocene in Central Mongolia.

Description: The Oligocene fossil deposits from Valley of Lakes in Central Mongolia have provided a wealth of rodent fossils. Among these, cricetids are a very important part. To date, only the Miocene genera have been described in detail. Here, we focus on the Oligocene genus Eucricetodon from this region. Eucricetodontinae are the most abundant fossils in the Oligocene Valley of Lakes faunas. The present study consists of the description of five species of cricetid rodents from 43 localities ranging in age from the early Oligocene to the early-late Oligocene. In addition to Eucricetodon asiaticus described in Mongolia in 1923, we have found Eucricetodon bagus and Eucricetodon jilantaiensis that were described from Nei Mongol and Eucricetodon occidentalis discovered in Kazakhstan. This taxonomical study provides new information regarding the evolution of the Cricetidae in Central and Eastern Asia during the Oligocene and, more particularly, regarding their phylogenetic relationships and the evolutionary trends.

Description: The recent find of an ethmosphenoid of Glyptopomus bystrowi (Gross 1941 ), a “glyptopomid” tetrapodomorph, in the Ketleri Formation (Upper Famennian, Upper Devonian) in western Latvia induced the description of historical material from this site and almost coeval localities in Central Russia (Orel-Saburovo Beds, Plavskian Regional Stage). Detailed morphological studies allowed recognition of new characters which support the taxonomic position of this species. Three-dimensional preservation of isolated elements enable the description of internal cranial structures, like the posterodorsolateral expansion of prenasal pits, the passage of some nerves and blood vessels, unknown in the previously described species of this genus. Despite minor differences, the vertebrate assemblages from these areas fit within the placoderm B. ciecere Zone (VII), which corresponds to the ?Upper postera –Lower expansa conodont Zone interval. These assemblages are virtually the same in their composition, except that durophagous placoderms and dipnoans are present in the Central Russian sites, in contrast to the Latvian ones. This could be explained by more significant marine influences.

Description: Fossil squamate faunas from the Hambach lignite mine are described here for the first time. The material comes from two stratigraphic levels—the older, Hambach 6C (MN 5), is dated to the middle Miocene, whereas the younger sites Hambach 11 and 13 are dated to late Pliocene (MN 16). Although fragmentary, the Hambach 6C material reveals a diversity of squamates in a particularly interesting period—the beginning of the middle Miocene. The chamaeleonid material consists of a squamosal and the jaw fragments. The squamosal is a previously unknown element in European fossil chameleons and it is tentatively allocated here to Chamaeleo aff. andrusovi . This clade is very important as a climatic indicator at the beginning of the middle Miocene in central Europe because the lower mean annual temperature limit for chameleons is 17.4 °C. In addition to the chamaeleonid, two types of lacertid lizards are recognised based on the preserved morphology. The anguid material is allocated to Pseudopus cf. ahnikoviensis . This material forms the youngest record of this taxon. Additional anguid material is attributed to Pseudopus sp. and Anguidae indet. Snake fauna here consists of the following taxa: Eoanilius , Bavarioboa , cf. Falseryx , “ Coluber ”, Texasophis , Telescopus , Natrix , cf. Naja and Vipera . Hambach 6C is the geologically youngest fossil site yielding remains of Eoanilius , possibly also youngest Falseryx (cf. Falseryx ). Although the Hambach 11 and 13 upper Pliocene (MN 16) sites exhibit low palaeodiversity, there is a large assemblage of Pseudopus cf. pannonicus. Natrix and Colubrinae indet. are identified in the snake population.