Articulated fossil fish skeletons with otoliths in situ provide a unique opportunity to link these two, otherwise independent data sets of skeletons and otoliths. They provide calibration points for otoliths also adding important information for the evolutionary interpretation of fishes. Here, we review nine articulated skeletons of gobies from the early Sarmatian of Dolje, Croatia, and Belgrade, Serbia, which were previously regarded as members of a single gobiid and a callionymid species. We found them to represent five different gobiid species belonging to five different genera, four of which are related to extant endemic Ponto-Caspian gobiid lineages. The species are: Aphia macrophthalma n.sp., Proneogobius n.gen. pullus (the only previously recognized species), Protobenthophilus n.gen. squamatus n.sp., Economidichthys triangularis (a species first described based on otoliths) and Hesperichthys n.gen. reductus n.sp. Five specimens contained otoliths in situ and a sixth shows imprints of otoliths which unfortunately must have been lost in the past, probably during preparation of the fossil. Together, they represent all five species recognized by skeletons, and three are linked to otolith-based species. Isolated otoliths have been reviewed from a variety of collections from Sarmatian strata in Austria, Bulgaria, Czechia, Romania and Slovakia resulting in the description of five new otolith-based species: Benthophilus? ovisulcus n.sp., Benthophilus styriacus n.sp., Protobenthophilus strashimirovi n.sp., Economidichthys altidorsalis n.sp. and Knipowitschia bulgarica n.sp. Our review demonstrates that all major endemic Ponto-Caspian gobiid lineages were already present during Sarmatian times, thereby pushing back their origin by approximately 5–10 myr in comparison to previously published dates for dichotomies. In our assessment, the origination of these lineages is linked to the early stage of separation of the Paratethys from the world oceans and the ecological changes that occurred during that time. These geological events parallel a dramatic increase in gobiid radiation and speciation, giving rise to many lineages, not all of which have persisted until today.

We describe here the first fossil otoliths from the Middle Miocene (Badenian and Sarmatian) of Belgrade, Serbia. They were obtained from Lower Badenian outcrops at Slanci and from upper Badenian and Sarmatian sediments recovered from four shallow wells near the village of Barajevo. The otoliths from the Lower Badenian of Slanci represent fishes typical for an open marine environment, characterized primarily by the mesopelagic families Myctophidae and Bregmacerotidae, a faunal composition that is also well known from other time equivalent locations in the Central Paratethys. The upper Badenian and Sarmatian composition of the fish fauna, in contrast, is dominated by otoliths of the family Gobiidae, indicating a sharp environmental shift from open marine to shallow water, probably slightly brackish environments, which is also confirmed by the faunal composition of mollusks, foraminifera, and ostracods. Most of the gobiid genera identified in the samples from Barajevo represent small fishes of the so-called sand gobies with Ponto-Caspian affinities, such as Economidichthys, Knipowitschia, or Pomatoschistus, or are entirely endemic to the Ponto-Caspian Basin, such as Hyrcanogobius. Another group of endemic Ponto-Caspian gobies is the first fossil record interpreted to represent the genus Proterorhinus. These and other finds currently being investigated indicate that the origin of the extant, rich, endemic gobiid fauna of the Ponto-Caspian Basin dates back to a crucial time in the development of Paratethys during the Middle Miocene when it segregated from the Mediterranean with the onset of phases of low salinity in the basin. In addition, we briefly discuss the distribution of certain gobiid species during Late Badenian and Sarmatian as it begins to emerge. The following new taxa are described based on fossil otoliths: Hyrcanogobius hesperis n.sp. and Proterorhinus vasilievae n.sp.

Elephantoid cheek teeth from the late Early and Middle Miocene of Europe frequently display mixtures of bunodont and zygodont features, making their taxonomical attributions difficult and subjective. Today, these teeth with ?intermediate? morphologies are attributed either to the mammutid species Zygolophodon turicensis, or to the gomphothere genus Gomphotherium - as a variation of G. angustidens or as a separate species G. subtapiroideum. This paper presents one such specimen, a fragmented lower third molar which originated from Miocene sandstones within the Krusevac Basin (possibly from the village of Bela Voda) in Central Serbia. We described the fossil and examined its metric properties in comparative context. Furthermore, we applied the semiquantitative method of WANG et al. (2016) in order to reduce subjectivity in our assessment of the degree of specimen?s zygodonty. Our results suggested that the specimen resembles Z. turicensis more closely than either G. angustidens and G. subtapiroideum, both in terms of the metrics and the degree of zygodonty. However, we were not able to make a firm taxonomical attribution, due to the fact that the specimen represents an isolated and incomplete fossil.

We describe four new species of the fossil genus Dapalis (Ambassidae), Dapalis absconditus sp. nov., Dapalis octospinus sp. nov., Dapalis parvus sp. nov. and Dapalis quintus sp. nov., based on articulated skeletons with otoliths in situ from a freshwater habitat of the lower Oligocene of Raljin/Strelac (Serbia). Besides in body shape (e.g., body length, body depth, head length, preanal length), the species differ in morphological characters like, e.g., the serration of the preopercle, the length of the first two spines of the first dorsal and the anal fin and the morphology of the sagittal otoliths (e.g., ratio of otolith height to otolith length, ratio of otolith width to otolith length). Together with D. pauciserratus, also described from Raljin, these four species represent the most species-rich assemblage of freshwater Dapalis known so far. The compartmentalization of the internal structure of the spines reveals the close relationship of Dapalis and extant Ambassidae. Additionally, we discuss a new character from the ventral field of the otolith, a ventral depression, only found in species from Raljin. This new character is unique among the European Dapalis species and allows us to separate these five species into two species groups.

The Middle Miocene of the Despotovac area contains sediments of the lower Middle Miocene (Badenian) and upper Middle Miocene (Sarmatian). The Middle Miocene deposition shows different local variations, but generally fits the evolution of the Central Paratethys. The Miocene sediments were ana - lyzed using paleontological and sedimentological methods. Based on the results of these investigations, the Golubac Formation (Badenian) and the Kamenovo Formation (Sarmatian), which had previously been defined and documented on the Kučevo sheet, were recognized for the first time within the sediments of the Middle Miocene study area on the sheet Lapovo 4.