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Seed morphology could provide significant characters for understanding the diversification of some clades in Bromeliaceae subfamily Bromelioideae, but little is known about the anatomical diversity and ontogeny of the seed coat in this diverse subfamily. We analysed the morphoanatomy of the seed coat for 48 species from 25 genera of the major lineages of Bromelioideae, from which we selected four species for ontogenetic analysis. Standard techniques for light microscopy were adapted for the anatomical study of seeds. Thirty-three variable characters were described and compared. Flattened or angular usually exappendiculate, tegmic-endotestal seeds, with secondarily thickened endotesta and undulate or costate tegmen, are common characteristics of the tankless lineages. Long oblongoid–obovoid, appendaged or exappendiculate, exclusively tegmic and mucilaginous seeds are common to core Bromelioideae. Anatomical features of the exotegmen and testa and the number of parenchyma layers in the raphe were more variable and especially useful in delimiting genera and some species. The ontogenetic analysis was essential to propose the primary morphological homology hypotheses for the seed coat characters. Seed coat morphoanatomical features offer a promising source of phylogenetically informative characters for integrative and character evolution approaches for Bromelioideae and possibly other subfamilies of Bromeliaceae. [ABSTRACT FROM AUTHOR]

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. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177, 66-77. [ABSTRACT FROM AUTHOR]