of all the encountered taxa, followed by Poaceae (8), Asteraceae (7) and Polygonaceae (6). Among the registered species we can highlight the first record in this state of Lilaeopsis minor Prez-Mor, Apiaceae.

The pollination ecology of Swartzia apetala Raddi var. apetala was studied in the restinga of Maricá, State of Rio de Janeiro, Brazil. S. apetala var. apetala is a shrub with asynchronic annual blooming, between the months of November and April (hot-rainy season). Each plant can exhibit more than one blooming episode in this period. Their flowers are hermaphrodites, apetalous, heterantherous, odoriferous, and the pollen represents the only reward offered to visitors. It is pollinized by species of Centris and Xylocopa, solitary and polyletic bees, which collect the pollen by means of vibratory movements. Other bees such as Apis mellifera, Pseudaugochloropsis graminea and Trigona spinipes are only pollen-thieves. In this variety of Swartzia vibrating is an efficient method to collect pollen from the anthers despite non-poricidal dehiscence.. The flowering phenology and the behavior of visitors influence the rate of outcrossing.
A ecologia da polinização de Swartzia apetala Raddi var. apetala foi estudada na restinga de Maricá, Estado do Rio de Janeiro, Brasil. S. apetala var. apetala é um arbusto com floração do tipo anual assincrônica, entre os meses de novembro e abril (estação quente- chuvosa). Cada planta pode apresentar mais de um episódio de floração neste período. As flores são hermafroditas, apétalas, heterândricas, odoríferas e o polem constitui a única recompensa oferecida aos visitantes. É polinizada por espécies de Centris e Xylocopa, abelhas solitárias e poliléticas, que coletam o polem através do método de vibração. Nesta variedade de Swartzia a vibração é um método eficiente de coleta de polem apesar das anteras apresentarem deiscência rimosa. Outras abelhas, como Apis mellifera, Pseudaugochloropsis graminea e Trigona spinipes, são pilhadoras de pólen. A fenologia da floração e o comportamento dos visitantes florais influenciam a taxa de fertilização cruzada

-(Female gametophyte development in Adesmia latifolia (Spreng.) Vog. (Leguminosae -Papilionoideae)). The female gametophyte has a monosporic origin and a Polygonum type development. The female gametophyte growth consumes a large part of the neighboring nucellar cells and, in the micropylar region, part of the nucellar epidermis and internal integument. The mature gametophyte is composed of only four cells due to the ephemeral characteristic of the antipodals. The synergids are pear-shaped cells with the formation of filiform apparatus. Their nuclei lie in the micropylar region and large vacuoles in the chalazal region, while the egg cell presents an opposite polarization. The central cell accumulates starch grains and the two polar nuclei approach the egg. Occasional development of two gametophytes was recorded. The closest to the micropyle develops fully, while the chalazal one remained in the tetranucleated stage. The embryological characters of A. latifolia are compared with those of other taxa within the Leguminosae, and the reproductive importance of multiple gametophyte formation for this species was discussed.Key words -Adesmia, embryo sac, embryology, female gametophyte, Leguminosae RESUMO -(Desenvolvimento do gametófito feminino em Adesmia latifolia (Spreng.) Vog. (Leguminosae -Papilionoideae)). O desenvolvimento do gametófito feminino é do tipo monospórico Polygonum. Durante o crescimento, o gametófito consome grande parte das células nucelares vizinhas e, na região micropilar, parte da epiderme nucelar e tegumento interno. O gametófito feminino maduro é composto por cinco núcleos e quatro células, pois as antípodas são efêmeras. As sinérgides são piriformes com formação de aparelho fibrilar. Essas apresentam o núcleo na região micropilar e grande vacúolo na região calazal, enquanto que a oosfera apresenta polarização contrária. A célula média armazena grãos de amido e os núcleos polares se aproximam do aparelho oosférico. Em alguns casos registrou-se o desenvolvimento de dois gametófitos, sendo que o mais próximo da micrópila se desenvolve completamente, enquanto que o calazal permanece no estádio tetranucleado. Foram feitas comparações taxonômicas entre os caracteres embriológicos dentro da família Leguminosae e foi discutida a importância reprodutiva da formação de gametófitos múltiplos para a espécie.

Aquatic ecosystems support species diversity, and knowledge of plant communities is essential for wetland conservation programs. This study provides a checklist of aquatic vascular plants of South Brazil and establishes their floristic affinities with bordering South America phytogeographical domains. The checklist was based on 52 sources, including 35 floristic lists, 17 regional taxonomic studies, and information from an electronic database on wetlands of South Brazil. Floristic similarities with published checklists for neighbouring regions were assessed. A total of 780 species distributed in 277 genera and 85 families of vascular plants were reported for South Brazil. Families with higher species richness were Cyperaceae (128), Poaceae (102), Asteraceae (69), Plantaginaceae (21), Lentibulariaceae (20), and Onagraceae (20). The most represented genera were Eleocharis (41) and Cyperus (24). A cluster analysis revealed high similarity with Iberá (Argentinian Chaco), Pampa and Atlantic Forest, and low similarity with Pantanal, Caatinga and the Amazon Rainforest. The high number of aquatic plant families recorded relative to temperate and tropical climates suggests a zone of biogeographical overlap in Southern Brazil. The compiled data set reveals high biodiversity of wetlands of South Brazil, provides a baseline for future research, and highlights the need for regional conservation planning.

Aquatic macrophytes show great phenotypic plasticity and are able to occupy environments with different physicochemical conditions. The present study aimed to characterize morphology and anatomical structure of the pondweed, Potamogeton polygonus Cham. & Schltdl., and to identify adaptive modifications of the plant in lotic and lentic environments. Sampling was carried out in Palmas and General Carneiro, Paraná state, southern Brazil. Ten individuals from each locality were collected. Morpho-anatomical characteristics of the roots, stems and leaves were measured. The anatomical structure was analyzed with light microscopy and scanning electron microscopy. Significant morphological and anatomical adaptive differences were observed between plants of the two environments.