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New material from the Famennian of Morocco in the southern Maider comprises chondrichthyan teeth(Thrinacodus, Cobelodus, Denaea, Stethacanthus), actinopterygian remains (scales, teeth and hemilepidotrichium) and one acanthodian scale. The absence of crushing teeth suggests deeper water environments for the Maider Basin than the Tafilalt Basin. Vertebrate microremains from the Famennian of Sardinia, includingSiamodusandJalodusteeth, are illustrated and described. Ichthyofaunal relationships of the North Gondwanan platform during the Famennian are examined.

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 partly articulated specimen of the Palaeozoic (Early Carboniferous) chondrichthyan ‘Cladodus’neilsoni Traquair from East Kilbride has been known since the late nineteenth century. As such, ‘C.’neilsoni Traquair has been cited in numerous publications, but it has become increasingly clear that its anatomy and systematic affinities are obscure. This comprehensive redescription of ‘C.’neilsoni reveals new details of the neurocranium (including presence of an otico-occipital fissure), dentition, visceral arches (clarifying the condition of the basibranchial pattern plus elongate copula), and pectoral fin. These data refute previously suggested synonymies, such as between ‘C’neilsoni and the contemporaneous Bearsden Stethacanthus. Attribution of ‘C.’neilsoni to the taxonomically unsupportable genus ‘Cladodus’ is rejected, and the species is redesignated as Gutturensisneilsoni gen. nov. Preliminary cladistic analysis places Gutturensisneilsoni within a polytomy including Stethacanthus, the symmoriid Cobelodus, and the root of a monophyletic group of neoselachian-like genera. ‘ Cladodont’ as a diagnostic term for early chondrichthyan teeth is found to be insufficiently precise, referring to an ill-defined grade of tooth morphologies present in a wide variety of Palaeozoic genera.

AND G. R. CASE. 1976. Cobelodus aculeatus (Cope), an anacanthous shark from Pennsylvanian black shales of North America. Palaeontographica Abt. A Bd. 154:107-157. 3. Inte relationships of early chondricha s, p. 1-14. In: Interrelationships of fishes. P. reenw od, R. S. Miles and C. Patterson (eds.). l. . Li n. Soc., Lond., suppl. 1, 53. 1. Paleozoic Elasmobranchii, p. -115. : andb ok of paleoic thyology. Vol. 3A. H. P. ltze (ed ). Gustav Fischer Verlag, New York, , AND S. RICHARDSON, JR. 1963. The paleoecological history of two Pennsylvanian black shales. Fieldiana: Geol. Mem. 4:1-352. , AND M. WILLIAMS. 1975. New evidence on the nature of the jaw suspension in Paleozoic anacanthous sharks. Palaeontology 18:333-341.