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Very diverse Early Permian chondrichthyan assemblages occur in the Asselian to Artinskian of the Middle and South Urals. They include numerous symmoriid teeth of “Denaea” decora Ivanov, Cobelodus obliquus sp. nov., Stethacanthus and Denaea; the teeth of the ctenacanthoid Heslerodus; the teeth of the synechodontiform Synechodus antiquus sp. nov.; and the teeth of taxa of doubtful affinities – Adamantina foliacea Ivanov, Cooleyella cf. C. fordi (Duffin & Ward), Cooleyella sp. A., as well the scales and denticles of various types. Two new species, Cobelodus obliquus and Synechodus antiquus, are described herein. The Early Permian chondrichthyan assemblages of Urals include a few taxa occurring only in that interval, as well taxa which were distributed in the Carboniferous and persisted into the Early Permian, such as Stethacanthus, Cobelodus, Denaea, “Denaea”, Lissodus, Heslerodus, “Symmorium”, Petalodus, Cooleyella and Adamantina. This occurrence of a synechodontid is the oldest in the world. The symmoriid sharks disappeared in the Middle Permian. The Permian shark faunas of the Urals contain a diverse assemblage of symmoriids, ctenacanthiods and synechodontiforms, but there are no xenacanthids were common in the Permian assemblages of Western Europe

The middle Famennian vertebrate localities of Central Russia yielded new micro- and macroremains of the chondrichthyansTuberospina nataliae nov. gen. et sp. and Symmorium sp.; struniiforms Strunius cf. rolandi Gross and Pycnacanthus fischeri nov. sp.; porolepiform ?Glyptolepis dellei Gross . The osteolepiform taxa Cryptolepis grossi Vorobyeva and ?Glyptopomus bystrowi Gross ; known before from the studied localities; are revised. A new family Pycnacanthidae nov. fam. is established on the ground of peculiar parasymphysial teeth fusion. Preliminary conodont dating is carried out based on local zonation.

Microvertebrates from limestones near the Burmese border town of Mae Sam Lap, northern Thailand, are dated as late Famennian by associated conodonts. The fauna contains the chondrichthyans Thrinacodus (Harpagodens) ferox, Symmorium? sp., “Cladodus,” cf. C. acutus, and two new taxa, Phoebodus australiensis, sp. nov., and Siamodus janvieri, gen. et sp. nov. Several types of chondrichthyan scales, actinopterygian scales and teeth, and rare acanthodian scales also occur in the fauna. Phoebodus australiensis, sp. nov., is also recognized from Australia and South China; Siamodus, gen. nov., is also recognized from the Late Devonian of South China. Thrinacodus ferox appears in the Late Devonian of Australia, South China, and Thailand, predating the occurrence of this species in Europe and North America (Carboniferous). These data suggest close affinity between the Shan-Thai, East Gondwana, and South China Terranes at the end of the Devonian.

Vertebrate remains have been discovered in the Frasnian and Famennian of the South Urals The ichthyofaunacontains representatives of Phoebodus; Stethacanthus; Symmorium; Protacrodus as well as placoderms; acanthodians; “crossopterygians” dipnoans and palaoniscids. Changes of the fish assemblages are examined. A review of the occurrences of Phoebodus is given.

A well-preserved portion of a body chamber of a coiled nautiloid (taxon uncertain) from the Kendrick Shale (Lower Pennsylvanian) of Floyd County, Kentucky, U.S.A., exhibits three comparatively large, nearly circular punctures and a circular indentation in the shell. These punctures are interpreted as representing an attack on the nautiloid by a cladodontid shark, most likely by the large symmoriid shark, Symmorium reniforme. We conclude that the punctures in the nautiloid body chamber were inflicted by three teeth in a single tooth file in the lower jaw of a specimen of 5. reniforme that was approximately 2.5 meters long. This nautiloid specimen is the first Paleozoic record of a chondrichthyan-cephalopod/ predator-prey relationship. We suggest, however, that this relationship was perhaps a common one and that other examples probably exist in collections of late Paleozoic ccphalopods. ?Paleozoic, Pennsylvanian, Symmorium reniforme, cephalopod. predation.