Pinus is the most invasive woody taxon, exceeded only by herbaceous plants. This study reports the reproductive biology and early establishment of Pinus elliottii Engelm. var.elliottii, describing its invasive properties in a protected natural area of the Brazilian coastal sandy plains. We evaluated the seed germination and rain, longevity of seed viability and the initial dynamics of the seedlings of Pinus elliottii var elliottii through field and laboratory experiments. We recorded a continuous seed rain of about 204.0 viable seeds m -2 per year, with a 90 % germination rate. The seeds exhibited a low longevity of viability in the soil and a dense, permanent seedling bank that may explain the high levels of pine invasion. The environmental impact caused by the pine's biological invasion suggests the recommendation for its immediate eradication, together with a restoration plan to restitute the native biodiversity gradually.

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The herbaceous vine Mandevilla funiformis (Vell.) K. Schum. occurs in open vegetation in the Southern Brazil. The present study was carried out in a sandbank, east of Florianópolis, Santa Catarina State. Floral morphology, nectar features (production pattern, removal effects, and standing crop), floral visitors (including pollinator, robber and thief of nectar), fruit set and seed germination of M. funiformis were studied. Every plant produced an average of 31.5 inflorescences. The average total volume and the average sugar concentration of nectar were 81 μL and 24%, respectively. The bees Epicharis (Anepicharis) dejeanii, Eufriesea violacea, Bombus (Fervidobombus) morio, the hummingbird Amazilia fimbriata, and two species of Hesperiidae were considered potential pollinators. The other species were considered consumers, nectar robbers or nectar thieves. Fruit set was 35.6% and average percentage of seed germination was 68%, indicating that visitors are efficient pollinators. This study was the first to report production and consumption of nectar in different floral stages (pre-anthesis, flower open, and after corolla abscission). The high and continuous production of nectar by M. funiformis, from floral buds in the pre-anthesis until after the corolla abscission show a real food availability in different ways (pollinators, consumers, robbers or thieves of nectar).

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