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CONIFER WOODS FROM THE MIDDLE CRETACEOUS OF NORTHERN MARANHAO STATE, BRAZIL In the present work, 13 silicified logs collected in the fossiliferous levels of the Alcantara Formation (Upper Albian-Lower Cenomanian estuarine deposits in northern Maranhao State, NE Brazil) were analyzed through petrographic slides applying parataxonomic approach. The gymnospermous araucarioid pattern is the prevailing pattern observed in the wood association, suggesting a possible relation to the Araucariaceae. Considering that pollen grains of Araucariacites australis were previously reported from the same sedimentary deposits where the sample came from, the presence of Araucariacea is assumed, mainly in the estuarine environment inferred for the region of Alcantara and Sao Luis. Conifers with abietoid wood pattern may be related to Taxaceae and probably throve in inland areas. The absence of angiospermous woods in the assemblage, opposed to the expressive representation in palynological analyses, can be attributed to a combination of taphonomic factors or, alternatively, to the development of conifer and angiosperm plants in distinct paleoenvironment during the middle Creataceous. The predominance of uninterrupted wood growth and rare evidences of partially interrupted wood growth patterns and the presence of radial desiccation cracks led to the inference of a stable paleoclimate, but with sporadic drought episodes during growing season, included in global scale in the equatorial humid belt in the boundary with the northern hot arid belt.