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The Inferior Oolite Formation, 'Wild Bed' of Quarr Hill, Chideock, Dorset is described in terms of ammonite biostratigraphy down to the resolution of biohorizons for a segment of the Aalenian Stage of the Middle Jurassic. A section is presented and descriptions of the ammonites of the families Graphoceratidae, Erycitidae, Hammatoceratidae and Lytoceratidae are made in conjunction with an assessment of available types along with new illustrations of specimens collected in-situ. Examples of other molluscs are cited and imaged. Lectotypes are designated for some of the species erected by S. S. Buckman from Chideock. Comparisons are made with successions in other areas of North-West Europe thus providing an improved correlation and relationships between different ammonite morpho-taxa. [ABSTRACT FROM AUTHOR]

Aptychi are reported from the Lower Aalenian Leioceras opalinum Zone and Subzone of the Khussa-Kardonik section in Karachay-Cherkessia (Kuban River Basin). They are associated with conchs of the ammonites genera Leioceras and Bredyia (superfamily Hildoceratoidea) and interpreted as their lower jaws. The Hildoceratoidea aptychi are referred to a form group defined by Trauth as ‘cornaptychi’. Wide valves with a straight apical angle (morph I) probably belong to Bredyia. Aptychi with an acute apical angle (wide in the basal part; morph II) and relatively narrow ones (morph III) belong to macroconchs and microconchs of Leioceras, respectively. Aptychi assignable to Leioceras opalinum are herein also reported from Southern Germany. [ABSTRACT FROM AUTHOR]

Members of the ammonite family Stephanoceratidae from the Middle Jurassic, Lower Bajocian, Laeviuscula to Humphriesianum zones of South West England are revised. These comprise faunas resulting from periodic migrations and possibly hybridization. The taxonomic positions of Teloceras Mascke, 1907, Kumatostephanus Buckman, 1922, Gibbistephanus Buckman, 1928 and Pseudoteloceras Pavia and Fernández-López, 2016 are considered in the light of new research. A new subfamily Kumatostephaninae is erected and hypotheses are presented regarding the evolution of some Early Bajocian stephanoceratids. Pseudoteloceras digbyi sp. nov. represents the earliest ‘ Teloceras -like’ morphology from the late Sauzei Zone. Refinement is made of the scheme of faunal horizons for the Lower Bajocian. [ABSTRACT FROM AUTHOR]