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One of the most completely preserved glacial sedimentary records from the Late Carboniferous to the Early Permian time corresponds to the Itarar e Group, which presents a large outcropping thickness in the northeastern border of Paran a Basin, especially in the State of São Paulo. This unit corresponds to the base of the Gondwana I Supersequence and is composed of continental to marine glacial and interglacial deposits. Based on some macrofloristic, lithostratigraphic and palynostratigraphic data, a formal scheme of the macrofloral succession is herein proposed for this interval, comprising five associations in ascending stratigraphic order namely: (1) Dwykea-Sublagenicula-Calamospora Association (recorded in Campinas Municipality), composed of lycophyte megaspores (Sublagenicula, Trileites and Calamospora sp.) and some bryophytes (Dwykea), concerning to a coastal glacial or coastal interglacial environment; (2) Eusphenopteris-Nothorhacopteris-Botrychiopsis Association (registered in Itapeva and Buri municipalities), composed of Eusphenopteris, Nothorhacopteris, Botrychiopsis, Paracalamites spp. along with Sphenophyllum, Koretrophyllites, Noeggerathiopsis and rare Cordaicarpus and Samaropsis e concerning to an interglacial deltaic plain associated to coal forming swamps with cold temperate hydro-hygrophilous vegetation; (3) Paranocladus-Ginkgophyllum-Brasilodendron Association (registered in Monte Mor Municipality), composed of the first conifers of the Paran a Basin (Paranocladus, Paranospermum and few Buriadia-type), lycophytes (Brasilodendron, Bumbudendron), Ginkgophyllum, Noeggerathiopsis, Samaropsis and Cordaicarpus and rare Nothorhacopteris, Botrychiopsis, Koretrophyllites and Sphenophyllum, interpreted as interglacial deltaic flood plain; (4) Dwykea-Sublagenicula-Calamospora Recurrent Association (recorded in Salto Municipality), composed of bryophytes (Dwykea) and lycopod megaspores, very similar to the first association, related to a coastal glacial or coastal interglacial depositional environment with a type-tundra vegetational cover; and (5) GangamopteriseArberia-Stephanophyllites Association (occurring in Tietê and Cerquilho municipalities), composed of the first glossopterid leaves and fructifications of the Paran a Basin (abundant Gangamopteris, Arberia, Arberiopsis and Hirsutum) and sphenophytes (Stephanophyllites and Phyllotheca), suggested as coastal prograding or alluvial environment, of an interglacial phase at the end of the sedimentary history of the Itarar e Group. The first four associations are of Pennsylvanian age while the last one is of Asselian-Sakmarian age.

The pre-glossopterid macroflora from the Volpe Ranch, in Monte Mor (State of São Paulo), was deposited during an interglacial context of the Itararé Group. It is characterized by the Paranocladus-Ginkgophyllum-Brasilodendron Association and is included in the middle-basal part of the Itararé Group outcrop, in the NE of the Paraná Basin. It is similar to the Argentine macrofloristic association Krauselcladus-Asterotheca Phytozone (ex-Interval Zone) and its palynofloristic contents belong to the Crucisaccites monoletus Palynozone (Kasimovian to Gzhelian). The conifers in this assemblage are represented by macro and microfossils and record the first level of occurrence of conifers in the basin. They are documented by leafy branches impressions and compressions of Paranocladus dusenii Florin and Buriadia heterophylla (Feistmantel) Seward and Sahni emend. Singh, and platyspermic seeds of the genus Paranospermum. Cuticular studies allowed to correlate the presence of Paranocladus dusenii with the platyspermic seeds Paranospermum cambuiense Ricardi-Branco and to identify a new species of Paranospermum as well. Previous palynological studies in this level led to the recognition of some pollen grains affinis to the gymnosperms (conifers, ginkgoaleans and pteridospermales) comprising monosaccate and bisaccate forms allocated to the genera Cannanoropollis, Plicatipollenites, Potonieisporites and Caheniasaccites indicating certain diversity of conifers as early as in Pennsylvanian. The association of conifers and Ginkgophyllum represents a mesoxerophytic tree community. The abundance of their fragmented material in the taphofloral assemblage suggests allochthonous origin transported toward a deltaic plain which were associated to a parautochthonous origin material. Their fossiliferous sandy matrix overlying the coal also suggests a higher energy agent of transport.Keywords: Early conifers; Paranocladus-Ginkgophyllum-Brasilodendron Association; Paraná Basin. ResumoA macroflora pré-glossopterídea do sítio Volpe, em Monte Mor (Estado de São Paulo), depositou-se, durante um interglacial do Grupo Itararé. Essa ocorrência caracteriza a Associação Paranocladus-Ginkgophyllum-Brasilodendron da porção médio-basal do Grupo Itararé aflorante no NE da bacia do Paraná. Corresponde à associação macroflorística argentina Fitozona Krauselcladus-Asterotheca (ex-Zona Intervalo) e seu conteúdo palinoflorístico pertence à Palinozona Crucisaccites monoletus (Kasimoviano a Gzheliano). As coníferas dessa associação estão representadas por macro e microfósseis e registram o nível mais inferior de ocorrência do grupo na bacia. São impressões e compressões de ramos folhosos de Paranocladus dusenii Florin e Buriadia heterophylla (Feistmantel) Seward and Sahni emend. Singh e de sementes platispérmicas do gênero Paranospermum. Estudos cuticulares possibilitaram relacionar a presença de Paranocladus dusenii com as sementes