The late Permian was a transformative time, which ended with one of the most significant extinction events in Earth's history. Fish assemblages are a major component of marine food webs. The macroevolution and biogeographic patterns of late Permian fish are currently insufficiently known. In this contribution, a late Permian ichthyofauna from the Kūmas quarry (southern Latvia) is described for the first time. The studied late Permian Latvian assemblage consisted of isolated chondrichthyan teeth putatively associated to ? Helodus sp., ?Acrodus sp., ? Omanoselache sp. and euselachian-type dermal denticles as well as many actinopterygian scales, numerous teeth and multiple unidentifiable microremains. This ichthyofaunal assemblage is very similar to the contemporaneous Lopingian complex of the Naujoji Akmenė formation from the Karpėnai quarry (northern Lithuania), despite the fact that the Kūmas assemblage is more diverse and abundant, in terms of fossil remains. The differences in the abundance of microremains could possibly be explained by a fresh water influx into the north-eastern Zechstein Basin margin, which probably reduced the salinity of the sea water. The new data enable a better understanding of the poorly known late Permian fish diversity from the north-eastern part of the basin. Keywords Microremains • Chondrichthyans • Actinopterygians • Histology • Permian • Baltic ResumenEl Pérmico superior fue un periodo transformador, que terminó con una de las extinciones más masivas de la historia de la Tierra. Los peces son un componente importante de las redes tróficas marinas. Los patrones macroevolutivos y biogeográficos de los peces del Pérmico superior han sido escasamente estudiados. En este trabajo describimos por primera vez la ictiofauna de la cantera de Kūmas (sur de Letonia). La asociación estudiada consiste en dientes de condrictios aislados asociados a ?Helodus sp., ? Acrodus sp., ? Omanoselache sp.; escamas de tipo Euselachii y de actinopterigios; numerosos dientes y otros microrestos no identificables. La asociación de ictiofauna descrita es muy similar a la actual del complejo

Combined sedimentological and taphonomical study of the siliciclastic sequence of the Tērvete Formation in the stratotypical area was aimed at revealing the formation of the three oryctocoenoses discovered and related structural and textural features of the deposits, as well as at detailed observation of the taphonomical peculiarities of the obtained palaeontological material. The fossil vertebrate assemblage is represented by 14 taxa comprising placoderms, acanthodians, sarcopterygians and actinopterygians. The three oryctocoenoses, first recognized in 2010, differ in the proportions of repeatedly buried material, in the number and degree of preservation of small and fragile skeletal elements, as well as in the evaluated current velocity and the transportation distance. Sedimentary concentrations of marine vertebrate remains, dominated by the antiarchs Bothriolepis ornata and B. jani, have been formed under the influence of fluvial and tidal processes in the shallow-water environment, deltaic or estuarine settings. Elongated placoderm and sarcopterygian bones are probably better indicators of the palaeoflow direction than acanthodian spines or sarcopterygian teeth

Lukševičs, E., Ahlberg, P.E., Stinkulis, Ģ., Vasiļkova, J. & Zupiņš, I. 2011: Frasnian vertebrate taphonomy and sedimentology of macrofossil concentrations from the Langsēde Cliff, Latvia. Lethaia, Vol. 45, pp. 356–370. The siliciclastic sequence of the Upper Devonian of Kurzeme, Western Latvia, is renowned for abundant vertebrate fossils, including the stem tetrapods Obruchevichthys gracilis and Ventastega curonica. During the first detailed taphonomic study of the vertebrate assemblage from the Ogre Formation cropping out at the Langsēde Cliff, Imula River, abundant vertebrate remains have been examined and identified as belonging to one psammosteid, two acanthodian and three sarcopterygian genera; the placoderm Bothriolepis maxima dominates the assemblage. Besides fully disarticulated placoderm and psammosteid plates, separate sarcopterygian scales and teeth, and acanthodian spines, partly articulated specimens including complete distal segments of Bothriolepis pectoral fins, Bothriolepis head shields and sarcopterygian lower jaws have been found. The size distribution of the placoderm bones demonstrates that the individuals within the assemblage are of approximately uniform age. Distinct zones have been traced within the horizontal distribution of the bones. These linear zones are almost perpendicular to the dominant dip azimuth of the cross‐beds and ripple‐laminae and most probably correspond to the depressions between subaqueous dunes. Concavity ratio varies significantly within the excavation area. The degree of fragmentation of the bones and disarticulation of the skeletons suggest that the carcasses were reworked and slightly transported before burial. Sedimentological data suggest deposition in a shallow marine environment under the influence of rapid currents. The fossiliferous bed consists of a basal bone conglomerate covered by a cross‐stratified sandstone with mud drapes, which is in turn overlain by ripple laminated sandstone, indicating the bones were buried by the gradual infilling of a tidal channel. All the Middle–Upper Devonian vertebrate bone‐beds from Latvia are associated with sandy to clayey deposits and have been formed in a sea‐coastal zone during rapid sedimentation episodes, but differ in fossil abundance and degree of preservation. □Agnathans, Devonian, facies analysis, fish, fossil assemblage, palaeoenvironment.

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Trace fossils and ichnofabrics were recognized in the Middle to Upper Devonian deposits of the East European Platform at the Onega Lake (NW Russia), developed as the Old Red Sandstone facies. The studied sequence is aged from the upper Givetian to the Middle Frasnian. The most diverse ichnoassemblage was ascertained in the earliest Frasnian (lower to middle part of the Andoma Formation), comprising the ichnogenera ?Arenituba, Cochlichnus, Cruziana, Diplocraterion, Lockeia, Palaeophycus, Planolites, Rusophycus, Skolithos, Teichichnus, and Undichna. Combination of ichnologic and sedimentary data points to the assumption that these deposits probably originated in wave- and tide-influenced environments, possibly in a brackish-water estuary. Towards the middle Frasnian, Skolithos-like trace fossil dominate; the ichnoassemblage can be attributed to the tidally influenced channels and bars