Morfo-anatomia e aspectos da biologia floral de Nectandra megapotamica (Spreng.) Mez (Lauraceae)

Abstract

Nectandra megapotamica (Spreng.) Mez is a common species in secondary forests of the area of Maringá, the State of Paraná, Brazil. The morphology and structures of its fowers and observations of anthesis, dehiscence of anthers, receptivity of the stigma and insect visitor registration are the objects of this investigation. Anthesis is diurnal and anthers only dehisce during the second day, when the stigma is not anymore receptive, characterizing dichogamy. The most frequent insect visitor were thrips (Order Thysanoptera). The tepals have a simple epidermis, with nonglandular and glandular hairs and paracytic stomata, and homogeneous parenchymatous mesophyll. Nectaries have secretory parenchyma, with vascular tissue, constituted mainly of phloem. The anthers possess a uniseriate hairy epidermis, endothecium, two or three middle layers and a tapetum with binucleate cells. The stigma presents multicellular uniseriate hairs. The ovary has a glabrous epidermis, a parenchyma with subepidermical meristematic activity and a rift as the vestigial sutural area. The single ovule is pendulous, anatropous and bitegmic.