The order Asparagales comprises 14 families, five of which occur in Brazil. Amaryllidaceae is a family of economic relevance and includes numerous ornamental genera. The genus Hippeastrum is widely distributed in Brazil and comprises 34 species, 11 of which occur in areas of restinga (coastal woodland) and Atlantic Forest in the state of Rio de Janeiro. The morphology of Hippeastrum has not been extensively studied in Brazil, where only a few systematic floristic surveys have been carried out with native species. In field studies and reviews of herbarium collections, we identified five Hippeastrum species occurring in areas of restinga in the state of Rio de Janeiro. The five species identified could be distinguished according to the following palynological characteristics: pollen grain size, polarity, pollen units, shape, aperture (number and type), exine sculpture, colpus length and pattern of sexine ornamentation. Of the five species identified, Hippeastrum aulicum Herb. and H. glaucescens (Ker Gawl.) Herb. were not identified in the field. Among the three species that were found in the field, H. striatum had the widest distribution in the study area, whereas the distribution of H. reticulatum was restricted to a single area of restinga, in the Jaconé district of the municipality of Saquarema. Through palynological examinations of specimens from herbaria in the state of Rio de Janeiro, we were able to confirm the identity of all five species of Hippeastrum studied. Our data represent a relevant contribution to increasing knowledge of this plant group in the region and will aid in future conservation efforts.

Foi realizado um estudo palinológico de 21 espécies da família Gesneriaceae reunidas em seis gêneros e três tribos: tribo Beslerieae -Besleria L. (4 spp.); tribo Episcieae - Codonanthe (Mart.) Hanst. (3 spp.), Nematanthus Schrad. (5 spp); tribo Sinningieae -Paliavana Vand. (1 sp.), Sinningia Nees (6 spp.) e Vanhouttea Lem. (2 spp.) ocorrentes no Estado do Rio de Janeiro, Brasil. Objetivou-se caracterizar e ampliar os dados morfológicos da família, em nível genérico ou específico, contribuindo assim, para uma delimitação mais precisa dos táxons. Os grãos de pólen foram acetolisados, medidos, descritos e ilustrados sob microscopia de luz. Para observar detalhes da superfície e abertura, grãos de pólen não acetolisados foram analisados em microscópio eletrônico de varredura (MEV). Os grãos de pólen das espécies estudadas variaram de pequenos a médios, suboblatos a prolatos; apresentaram cólporos ou colpos e o número de aberturas foi constante para todas as espécies analisadas (3-aperturados). A ornamentação da sexina variou entre escabrada, perfurada, rugulada, microrreticulada e reticulada. Os resultados mostraram que a morfologia polínica é bem definida entre as espécies estudadas, variou dentro e entre as tribos e gêneros, podendo ser usada para identificar os táxons e sustentar o caráter euripalinológico de Gesneriaceae.

This work deals with the study of pollen of 21 species from the family Gesneriaceae found in six genera, divided into three tribes: Beslerieae tribe - Besleria L. (4 spp.) Episcieae tribe - Codonanthe (Mart.) Hanst. (3 spp.) Nematanthus Schrad. (5 spp); Sinningieae tribe - Paliavana Vand. (1 sp.), Sinningia Nees (6 spp.) and Vanhouttea Lem. (2 spp.), occurring in Rio de Janeiro state, Brazil. We aim to characterize and expand the morphological data of the family, at the general or specific level, thus contributing to a more precise delimitation of taxa. The pollen grains were acetolysed, measured, described and illustrated using light microscopy. To see details of the surface and opening, non-acetolysed pollen grains were examined with a scanning electron microscope (SEM). The pollen grains of the species studied ranged from small to medium, suboblate to prolate; they had colpores or colpes and the number of openings was constant for all species (3-aperture). Ornamentation of the sexine ranged from scabrous to perforated, rugulate, microrreticulate and reticulated. The results showed that pollen morphology is well defined for the species studied; it varied within and between tribes and genera, can be used to identify taxa and maintains the eurypalynological character of the family Gesneriaceae.