The study was carried out in the area of the Magela Project (04º 35' 20" S and 43º 49' 55,2" W) owned by MARGUSA Enterprise (Maranhão Gusa S/A), located in the Municipality of Codó, State of Maranhão. The forest cover belongs to the Open Ombrophylous Forest with lianas (OOFliana) and to the Open Ombrophylous Forest with palms (OOFpalm). The objective was to analyze the floristic composition and horizontal structure of the OOFliana and OOFpalm. In 50 x 200 m plots, all individuals with DBH > 15 cm (inclusion level I) were measured, and in 5 x 50 m subplots, individuals with 5 cm < DBH < 15 cm (inclusion level II) were included. The OOFpalm formation showed the highest floristic diversity. Species with higher ecological importance in OOFliana were: Cenostigma macrophyllum Tul. (Leguminosae), Galipea jasminiflora (A. St.-Hil.) Engl. (Rutaceae) e Hymenaea parvifolia Huber (Leguminosae). In OOFpalms, the most important species were: Attalea speciosa Mart. Ex Spreng. (Arecaceae), Actinostemon klotzshii (Didr.) Pax (Euphorbiaceae) e Cenostigma macrophyllum.
Open Ombrophylous Forest; Floristic composition; horizontal structure
