The Malpiguiaceae species studied are pollinator-dependent, as spontaneous self-pollination is limited by herkogamy, protogyny and the stigmatic cuticle. Both the oil- and pollen-collecting behaviours of the pollinators favour the rupture of the stigmatic cuticle and the deposition of pollen on or inside the stigmas. As fruit-set rates in natural conditions are low, population fragmentation may have limited the sexual reproduction of these species.

Building bridges between environmental and political agendas is essential nowadays in face of the increasing human pressure on natural environments, including wetlands. Wetlands provide critical ecosystem services for humanity and can generate a considerable direct or indirect income to the local communities. To meet many of the sustainable development goals, we need to move our trajectory from the current environmental destructive development to a wiser wetland use. The current article contain a proposed agenda for the Pantanal aiming the improvement of public policy for conservation in the Pantanal, one of the largest, most diverse, and continuous inland wetland in the world. We suggest and discuss a list of 11 essential interfaces between science, policy, and development in region linked to the proposed agenda. We believe that a functional science network can booster the collaborative capability to generate creative ideas and solutions to address the big challenges faced by the Pantanal wetland.

1. The temporal dynamics of plant phenology and pollinator abundance across seasons should influence the structure of plant-pollinator interaction networks.Nevertheless, such dynamics are seldom considered, especially for diverse tropical networks.2. Here, we evaluated the temporal variation of four plant-pollinator networks in two seasonal ecosystems in Central Brazil (Cerrado and Pantanal). Data were gathered on a monthly basis over 1 year for each network. We characterized seasonal and temporal shifts in plant-pollinator interactions, using temporally discrete networks. We predicted that the greater floral availability in the rainy season would allow for finer partitioning of the floral niche by the pollinators, i.e. higher specialization patterns as previously described across large spatial gradients.Finally, we also evaluated how sampling restricted to peak flowering period may affect the characterization of the networks.3. Contrary to our expectations, we found that dry season networks, although characterized by lower floral resource richness and abundance, showed higher levels of network-wide interaction partitioning (complementary specialization and modularity). For nestedness, though, this between-seasons difference was not consistent. Reduced resource availability in the dry season may promote higher interspecific competition among pollinators leading to reduced niche overlap, thus explaining the increase in specialization. There were no consistent differences between seasons in species-level indices,indicating that higher network level specialization is an emergent property only seen when considering the entire network. However, bees presented higher values of specialization and species strength in relation to other groups such as flies and wasps, suggesting that some plant species frequently associated with bees are used only by this group.5. Our study also indicates that targeted data collection during peak flowering generates higher estimates of network specialization, possibly because species activity spans longer periods than the targeted time frame. Hence, depending on the period of data collection, different structural values for the networks of interactions may be found.6. Synthesis. Plant-pollinator networks from tropical environments have structural properties that vary according to seasons, which should be taken into account in the description of the complex systems of interactions between plants and their pollinators in these areas. K E Y W O R D SCerrado, functional diversity, modularity, nestedness, network sampling, Pantanal, resource availability, seasonality | 2411Journal of Ecology SOUZA et Al.

-(Reproductive phenology, pollination and reproduction of Dipteryx alata Vogel (Leguminosae-Papilionoideae) in Mato Grosso do Sul, Brazil). The reproductive biology of Dipteryx alata was studied from September/2004 through August/2006. Dipteryx alata is a tree that blooms during the rainy season (4-6 months) and fructification peak occurs in the dry season. There are annual variations in the intensity of flowering and fructification. The flowers are zygomorphic, papilionaceous, hermaphrodite, relatively small, odoriferous, diurnal and last up to 10 hours. The calyx has two petaloid lobules and the corolla is formed by the standard, wings and the petals of the keel. Pollen viability is 94.4%. The stigma is covered by a pelicule that prevents pollen adherence and limits the spontaneous self-pollination. Nectar is produced in a chamber, in small quantity (1.45 µL) and with concentration of 25%. Dipteryx alata has keel flowers and the mechanism of pollination is intermediate between the explosive and valvular types. This species is alogamous, has late acting selfincompatibility and high rate of abortion (ER = 0.45). The main pollinator is Xylocopa suspecta (16.6% of visits), which visits legitimately the flowers and presents trap lining behavior, that promotes pollen flow between plants. Although the visitation rate of Pseudaugochlora graminea (15.3%) and Apis mellifera (39.5%) bees are relatively high, they are not good pollinators (pollination efficiency = 3.5 and 0, respectively), because they generally did not accomplish movement between plants. Apis mellifera robbed nectar in 45.5% of visits. The increasing of seed production in natural populations of D. alata depends on the maintenance of effective pollinators (solitary bees), and it is recommended the management of A. mellifera.Key words -Apis mellifera, cumbaru, management, self incompatibility, Xylocopa suspecta RESUMO -(Fenologia reprodutiva, polinização e reprodução de Dipteryx alata Vogel (Leguminosae-Papilionoideae) em Mato Grosso do Sul, Brasil). A biologia reprodutiva de Dipteryx alata foi estudada de setembro/2004 a agosto/2006. Dipteryx alata é arbórea, floresce na estação chuvosa (4-6 meses) e o pico de frutificação ocorre na estação seca. A espécie apresentou variação na intensidade de floração e frutificação entre os anos. As flores são zigomorfas, papilionáceas, hermafroditas, relativamente pequenas, odoríferas, diurnas e duram até 10 horas. O cálice possui dois lobos petalóides e a corola é formada pelo estandarte, alas e as pétalas da quilha. As anteras produzem pólen com 94,4% de viabilidade. O estigma é recoberto por película que limita a autopolinização espontânea, impedindo a aderência do pólen. Néctar é armazenado em câmara, em pequena quantidade (1,45 µL) e com concentração de 25%. Dipteryx alata tem flores de quilha e possui mecanismo de polinização intermediário entre os tipos explosivo e valvular. Esta espécie é alógama, possui auto-incompatibilidade de ação tardia e elevada taxa de aborto (ER = 0,45). Xylocopa suspecta (16,6...

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-(Ruellia brevifolia (Pohl) Ezcurra (Acanthaceae): flowering phenology, pollination biology and reproduction). The reproductive biology of Ruellia brevifolia was studied in two populations of southeastern Brazil. R. brevifolia is a shrublet that grows in dense clumps in open but shaded areas. This Acanthaceae blooms all year round and produces chasmogamous (CH) and cleistogamous (CL) flowers during the rainy and the dry season, respectively. Cleistogamy is of the "clymatic" type, and produces seeds in the most stressful period of the year. CH flowers are tubular, red and odourless, protogynous, and may be herkogamous or not; anthesis is diurnal, and they last two days. Nectar is produced in small amounts (5.2 µl ± 2.36) and its concentration is about 30%. CL flowers resemble CH buds, except for their pale color. Pollen/ovule ratio of CL flowers is 60% lesser than that of CH flowers because of the small amount of pollen grains. This Ruellia is self-compatible, but protogyny and herkogamy favour allogamy; spontaneous self-pollination in CH flowers seems to be related to the non herkogamous flowers. The hummingbird Amazilia lactea and the butterflies Heliconius etilla narcaea and Phoebis argante are the major pollinators of R. brevifolia. The hummingbirds visit R. brevifolia only during flowering peaks, when there is a high number of flowers. It seems plausible that both the small nectar volume per flower and the trap-line foraging strategy of A. lactea promote mainly outcrossing. The butterflies visit flowers mainly in the same plant group, but during low floral density periods they fly greater distances also favouring outcrossing.RESUMO -(Ruellia brevifolia (Pohl) Ezcurra (Acanthaceae): fenologia da floração, biologia da polinização e reprodução). A biologia reprodutiva de Ruellia brevifolia foi estudada em populações naturais do sudeste brasileiro. R. brevifolia é um subarbusto que forma agrupamentos densos em áreas abertas mas sombreadas e floresce o ano todo, produzindo flores casmógamas (CH) e cleistógamas (CL) nas estações úmida e seca, respectivamente. A cleistogamia é do tipo climática, originando sementes no período de maior estresse ambiental. Flores CH são inodoras e possuem corola tubulosa e vermelha, sendo hercogâmicas ou não; apresentam protoginia, antese diurna e duram dois dias. Néctar é o principal recurso floral, sendo produzido em baixa quantidade (5,2 µl ± 2,36) e com concentração de açúcares em torno de 30%. Flores CL assemelham-se a botões jovens de flores CH e apresentam redução de tamanho principalmente no androceu e na corola. A razão pólen/óvulo das flores CL é ca. de 60% menor que a das flores CH devido a menor quantidade de grãos de pólen. R. brevifolia é autocompatível embora alogamia seja favorecida pela protoginia e pelas flores hercogâmicas. Autopolinização espontânea parece estar relacionada às flores CH não hercogâmicas. Beija-flores, principalmente Amazilia lactea, e borboletas, em especial Heliconius etilla narcaea e Phoebis argante, são os polinizadores de R. brevifoli...

We present the floristic composition and reproductive phenological data for a remnant of Arborized Stepic Savanna, vegetation type of humid Chaco, Porto Murtinho, Mato Grosso do Sul State, Brazil. We recorded 87 species of 31 families; Leguminosae presented the highest richness (14 species), followed by Malvaceae (9), Cactaceae (7) and Asteraceae (7). The herbaceous layer is relevant in the seasonal studied community (53.5% of the species) and there is predominance of non-perennial species (hemicryptophytes and therophytes), which demonstrate the importance of underground structures or seed banks in the vegetation. The community has continual flowering and fruiting with highest intensity in the rainy season, the most favorable period for plant growth and reproduction. The predominance of autochoric species in relation to anemochoric and zoochoric ones suggests partial independence of seed/fruit dispersal agents. Zoochorous species predominated in the rainy season, whereas anemochorous and autochorous species were more representative in the dry season.

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