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Vertebrate macroevolution has been punctuated by fundamental habitat transitions from shallow marine origins to terrestrial, freshwater, and aerial environments. Invasion of the deep sea is a less well-known ecological shift because of low fossilization potential and continual loss of abyssal fossil record by ocean floor subduction. Therefore, there has been a lack of convincing evidence of bottom-living vertebrates from pre-Paleogene deep seas. Here, we describe trace fossils from abyssal plain turbidites of the Tethys Ocean, which, combined with nannofossil dating, indicate that fishes have occupied the deep seafloor since at least the Early Cretaceous (Hauterivian-Barremian). These structures are identical to those produced by modern demersal fishes that feed by either scratching the substrate or expose their prey by water flow generated by suction or jetting. The trace fossils suggest activity of at least three fish species exploiting a productive abyssal invertebrate sediment fauna. These observations are consistent with Early Cretaceous vertebrate transition to the deep sea triggered by the availability of new food sources. Our results anticipate the appearance of deep-seafloor fishes in the fossil record by over 80 My while reassessing the mode of vertebrate colonization of the deep sea. [ABSTRACT FROM AUTHOR]

The ghost shrimp Turbiocheir minutospinata has so far been known only from its holotype from the Eocene/Oligocene rocks of Río Turbio, Patagonia in Argentina. Recently, the additional specimen has been found in the Eocene strata of the Boca Lebu Formation of the Arauco Basin, Chile. New material adds information on the morphology of chelipeds and allows evaluation of the degree of heterochely of the studied ghost shrimp. Moreover, comparison of Turbiocheir minutospinata with extant ghost shrimp taxa allows synonymisation of Turbiocheir with Anacalliax. With this act the fossil record of Anacalliax is extended into early Eocene. The occurrence of Anacalliax minutospinata comb. nov. is proposed to represent a reliable calibration point for Anacalliacidae, which was not available until now. [ABSTRACT FROM AUTHOR]

The ichnospecies Gastrochaneolites dijugus Kelly and Bromley 1984 and Teredolites longissimus Kelly and Bromley 1984, attributed to the boring activity of gastrochaenoid and pholadid bivalves, are described respectively from the Miocene Vilanova Basin and the Pliocene Almería-Níjar Basin. Miocene and Pliocene traces are preserved as positive casts associated to invertebrate shells and wood fragments, respectively; in both cases, the host substrate (shells and wood) has been lost almost entirely by different taphonomic processes (mainly dissolution). For the first time in the fossil record, the complete ichnogenetic sequence of these two ichnospecies is described and figured. [ABSTRACT FROM AUTHOR]

Modern fish are able to produce a plethora of different traces (both bioturbation and bioerosion structures) according to several behaviours, yet only five ichnotaxa have been interpreted as produced by the activity of fish in the fossil record. Many taphonomic factors may favour the non-fossilization of many of these traces and, even fossilized, they could have been misinterpreted. In this contribution, shallow and bilobed traces produced by the feeding activity of the perciform fish Diplodus vulgaris (Sparidae) in the estuary of the Piedras River (Lepe, Huelva, SW Spain) are described. Neoichnological study and comparison of these bioturbation structures with the fossil record allow associating them as Cruziana - and Rusophycus -like traces, i.e. traces with features very similar to those of such ichnogenera. Since these ichnotaxa have been commonly interpreted as the result of the locomotion and resting of different kinds of invertebrates, in order to get a better understanding of the marine and continental fossil record, we also propose taking into account fish as potential producers of this kind of traces in future paleoichnological studies. [ABSTRACT FROM AUTHOR]

Avian traces occurring in Pleistocene aeolianite and beach deposits are rare and relatively poorly known, despite being good paleoenvironmental indicators. Passeriform and raptorial birds are especially rare in the track fossil record. Exceptional tracksites were found in the Malhão formation, a Pleistocene coastal aeolianite unit from the SW mainland Portugal, with subunits in the interval ∼187 to ∼27 ka. Two new forms of avian traces were identified, Corvidichnus odemirensis and Buboichnus vicentinus - attributed to the locomotion of Western jackdaw and the locomotion and predation/feeding behaviour of a large Eagle-owl. The last trace fossil may correspond to the first evidence of a raptorial bird-prey interaction found in action in the fossil record. Typical shorebird tracks and trackways attributed to gulls (Laridae) and curlews, and others tentatively compared with Rallidae, such as Eurasian coot, are also discussed within the aeolianite ichnoassemblages. The tracks here described are the first avian ichnotaxa from the Pleistocene of Europe. • Two new bird tracksites are described from the Middle-to-Late Pleistocene coastal aeolianites of SW Portugal. • Corvidichnus and Buboichnus vicentinus igenn. nov. record behaviors of western jackdaw and a large eagle-owl. • Passeriform and raptorial birds are especially rare in the track fossil record. • A trace fossil of raptorial bird-prey interaction is described for the first time. • These tracks are the first avian ichnotaxa from the Pleistocene of Europe. [ABSTRACT FROM AUTHOR]

Abstract: The low Lower Cambrian rocks from the Sierra de Córdoba contain one of the best successions in Europe, which consists of well exposed mixed facies with abundant fossil assemblages showing long stratigraphical ranges throughout the Pedroche Formation. These assemblages include diverse Ovetian archaeocyaths, trilobites, small shelly fossils, calcimicrobes, trace fossils and stromatolites. Trace fossils are still poorly known, and thus they are the main objective of this work. Ichnological data are obtained from the Arroyo de Pedroche 1, Arroyo de Pedroche 2 and Puente de Hierro sections. Trace fossils include the ichnogenera Bergaueria, aff. Bilinichnus, Cochlichnus, aff. Cosmorhaphe?, Cylindrichnus, Dactyloidites, Dimorphichnus, Diplichnites, Monocraterion, Palaeophycus, aff. Phycodes, Planolites, Psammichnites, Rusophycus, Skolithos, Torrowangea and Treptichnus, as well as faecal pellets, meniscate trace fossils and others. They are abundant in shales and sandstones, and indicate important changes in the benthic conditions with respect to the underlying Torreárboles Formation. Changes in fossil assemblages within Member I of the Pedroche Formation indicate palaeoecological disruptions, which led to the disappearance of numerous archaeocyath species and the decrease of stromatolite biodiversity. This was followed by dominance of trilobite and brachiopod assemblages, accompanied by trace fossils of the Psammichnites ichnosp. A ichnoassociation. This biotic turnover (Pedroche event) occurred at the lower part of the archaeocyath Zone III, within the Bigotina bivallata biozone. The diagnoses of the ichnospecies Cochlichnus anguineus and Dactyloidites cabanasi are emended. [Copyright &y& Elsevier]

Abstract: The low Lower Cambrian rocks from the Sierra de Córdoba, which consist of well exposed mixed facies and abundant fossil assemblages showing long stratigraphic ranges throughout the Pedroche Formation, represent one of the best successions of this age in Europe. The fossil assemblages include diverse Ovetian archaeocyaths, trilobites, small shelly fossils, calcimicrobia, trace fossils and stromatolites. Trilobites are still poorly known, and thus they are the main objective of this work. The trilobites studied originate from three sections. At the Arroyo de Pedroche 1 section, cf. Bigotinella and Bigotina bivallata are replaced towards the top by Lemdadella linaresae, Lemdadella perejoni sp. nov. and, finally, by Eoredlichia cf. ovetensis. At the Arroyo de Pedroche 2 section, Lemdadella linaresae is replaced by Lemdadella perejoni sp. nov. and Eoredlichia cf. ovetensis, while at the Puente de Hierro section Lemdadella linaresae, L. aff. linaresae and Serrania verae occur together. These new biostratigraphic data confirm that the Pedroche Formation, originally defined as a repetitive sequence of four members, contains only two members. The new trilobite discoveries permit the first tentative correlation between the Ovetian of southern Spain and Lower Cambrian strata from the High Atlas (Morocco), Siberia, Antarctica and Carteret (France). [Copyright &y& Elsevier]