Acta bot. bras. 24(3): 765-779. 2010. IntroductionBromeliaceae currently covers 58 genera and 3172 species (Luther 2008). The family is included in the order Poales (APG II 2003) and has a typically Neotropical geographic distribution (Smith & Downs 1974). Its representatives are epiphytic, rupicolous or terricolous herbs, whose fruits are classifi ed as capsules or berries (Benzing 2000).Although the monophyletic origin of this family has been confi rmed (Ranker et al. 1990;Horres et al. 2000;Barfuss et al. 2005), the origins, phylogenetic relations and circumscriptions of the subfamilies, genera and species are as yet little known, and, above all, there is much diffi culty in delimiting genera and species. Therefore, the infrafamilial relations of Bromeliaceae have been the target of several investigations, but the phylogeny of the group is still being intensely discussed, with signifi cant differences among the authors.Traditionally, Bromeliaceae is divided into three subfamilies: Pitcairnioideae, Tillandsioideae and Bromelioideae, distinguished especially by the morphology of fl owers, fruits and seeds (Smith & Downs 1974). However, Givnish et al. (2007) proposed a new arrangement for the family based on molecular data, increasing the number of subfamilies to eight (Brocchinioideae, Lindmanioideae, Tillandsioideae, Hechtioideae, Navioideae, Pitcairnioideae, Puyoideae and Bromelioideae). This new classifi cation became more natural, so that the recognized subfamilies are monophyletic.As for fruit morphology and anatomy, several studies have shown that they are used to delimit or resolve taxonomic problems among species, genera, tribes and even monotypical families, such as Tobe et al. (1992), Smitt et al. (1995), Doweld (1998), Decraene et al. (2000), Doweld (2001) and Moon & Hong (2006). Moreover, this type of investigation is essential to help understand the true origin of the fruits of angiosperms and to contribute to making their classifi cation more uniform. As the reproductive organ responsible for seed dispersal, through morphoanatomical studies, the fruit helps us to understand how the species are dispersed and these are important data for proposals to conserve biodiversity.Despite what has been presented about the importance of structural studies in fruit, these are few in comparison to those on other plant organs, and very few angiosperm families have a representative number of publications in this fi eld, as in the case of Fabaceae and Anacardiaceae. In contrast to these, only two anatomical studies of fruit were recorded for Bromeliaceae, in Ananas comosus (Okimoto 1948) and Tillandsia tricholepis (Morra et al. 2002).Therefore, the purpose of this study is to characterize and compare the morphoanatomy and ontogeny of the fruit of six species of Bromeliaceae -Aechmea calyculata and RESUMO -(Morfoanatomia e ontogenia de fruto em espécies de Bromeliaceae). O presente estudo objetivou apresentar um panorama acerca da estrutura de frutos em Bromeliaceae, devido à extrema escassez de estudos nessa área...

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In Bromelioideae, the so-called nidularioid complex contains closely related genera, the circumscription of which has been problematic. The goal of this study was to describe the ovary and ovule anatomy of six species of the nidularioid complex belonging to Canistropsis, Canistrum, Edmundoa, Neoregelia, Nidularium and Wittrockia and to use these characters in a parsimony analysis of relationships. In all analysed species, schizogenous-type aerenchyma is present in the ovarian mesophyll. Edmundoa lindenii has trichomes on the ovary surface, and this character appears to be an autapomorphy for the species. Canistrum aurantiacum exhibited some autapomorphies, such as four cell layers in the outer integument, non-elongated cells in the nucellar epidermis and three or four layers of cells in the parietal tissue. In the remaining species of the complex, the presence of transversally orientated ovules and anticlinally elongated cells in the outer integument in the micropylar region appear to be synapomorphies. Canistrum aurantiacum shares few characters with the other species; these results and the latest phylogenetic analysis show that Canistrum spp. do not belong to the current nidularioid clade.

Tillandsioideae are composed of nine genera, most of these with unclear delimitation. The morphoanatomy of ovules and ovaries of 83 species from seven different genera was studied under light or scanning electron microscopy to contribute to the understanding of the relationships in the group. The nucellar epidermis and the parietal tissue showed a regular pattern for all Tillandsioideae. The presence of chalazal appendages, however, and their shape and size varied between the genera analysed. Most species had a single acuminate chalazal appendage. Catopsis was the only genus with multiple appendages. Guzmania and Racinaea lacked this structure. The integuments also presented a variable length and thickness among the different genera. The four to six layers of the outer integument were unique in Catopsis and the three cell layers condition in the inner integument of Tillandsia should be a retained feature as it was also observed in Catopsis. Many characteristics in ovule morphology presented here have great systematic value for distinguishing genera of the Tillandsioideae. In addition, these features can also help in the understanding of ovule evolution in Bromeliaceae as a whole.

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