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Holcoptychites is known only from the Neuque´n Basin, Argentina, but appears close to the more widespread genera Jeanthieuloyites and Spitidiscus. Thus it is placed in the subfamily Spitidiscinae (Family Holcodiscidae). Previously described Holcoptychites species are revised and their taxonomy clarified, while one new species is left under open nomenclature. The sequence of forms allows two subzones to be recognized. These are correlated provisionally with the lowest Hauterivian Acanthodiscus radiatus Zone of the Mediterranean region. [Copyright &y& Elsevier]

New material and the investigation of old collections provided some 150 specimens of Early Cretaceous brachiopods from the Mecsek Mountains, Hungary. Taxonomic evaluation resulted in the identification of some species previously unknown from Hungary and confirmed the presence of some previously described species, too. In this paper Fortunella cf. fortunae Calzada, 1985, Lacunosella hoheneggeri (Suess, 1858), Monticlarella remesi Nekvasilova, 1977, Moutonithyris moutoniana (d'Orbigny, 1847), Karadagella ? aff. bilimeki (Suess, 1858), Nucleata veronica Nekvasilova, 1980 are described. This fauna is rather endemic. All the specimens reveal a unique phenomenon: they exhibit 25–70% larger average dimensions compared to populations of their closest relatives or type localities. The uniform size increase of these brachiopods may be linked to hydrothermal processes of the sea-floor. Lately, a discovery from the Tyrrhenian Sea offers a Recent, present day analogue to this enigmatic palaeoenvironment. Palaeobiogeographic comparison of this small endemic fauna with eight others, mainly Hauterivian and Tethyan brachiopod assemblages reveals the distinct Sub-Tethyan domain consisting of the faunas from Zengővárkony, Codlea (Eastern Carpathians) and Štramberk (Czechia). This strengthens previously described affinities and relationships of these faunas and helps to clarify the Cretaceous palaeogeographic position of the Mecsek Mountains. [ABSTRACT FROM AUTHOR]