Phylogenetic analyses and molecular dating estimates based on chloroplast DNA sequences were used to establish the relationships of the southern and Southeast Asian Crypteroniaceae and elucidate their biogeographic history. Maximum parsimony and likelihood analyses of rbcL sequences suggested that Crypteroniaceae should be restricted to Crypteronia, Axinandra, and Dactylocladus and that Crypteroniaceae, so defined, are sister to a clade formed by three small African taxa (Oliniaceae, Penaeaceae, and Rhynchocalycaceae) and the monotypic Central and South American Alzateaceae. Three molecular dating approaches (maximum-likelihood under a molecular clock, Langley-Fitch, and penalized-likelihood) were used to infer the age of Crypteroniaceae using both paleobotanic and geologic calibrations. Comparisons among these three methods revealed significant lineage effects in rbcL sequences. Clock-independent dating estimates suggested that divergence of Crypteroniaceae from its African and South American relatives coincided with the breakup of Gondwana, and that India likely served as a "raft" transporting Crypteroniaceae to Asia, with later expansion to Southeast Asia. To our knowledge, Crypteroniaceae are the first plant group for which the out-of-India hypothesis is well corroborated by molecular-based estimates of divergence times.

Based on nucleotide sequences from three chloroplast DNA regions (rps16, rpl16 , trnT‐trnL), we infer detailed phylogenetic relationships within the subfamily Thunbergioideae (Acanthaceae) and among major lineages of the family as a whole. Taxa were sampled to cover the geographic distribution of Thunbergioideae and to include all subgenera of the largest genus Thunbergia. All other major lineages of Acanthaceae were sampled to test monophyly and intrafamilial position of Thunbergioideae. Both parsimony and Bayesian analyses support Thunbergioideae as monophyletic. The mangrove genus Avicennia is consistently placed as sister to Thunbergioideae although with only moderate support. Thunbergia and Mendoncia are both monophyletic in all analyses, and Mendoncia is placed as sister to Thunbergia plus Pseudocalyx. Relationships within the two largest genera Mendoncia and Thunbergia are highly resolved and most branches are strongly supported. Our results suggest that the existing morphology‐based classification of Thunbergia partially holds, but needs revision. Based on the phylogenetic relationships we found it likely that a twining habit is ancestral for the genus Thunbergia. The thecal awns, characteristic for many species in the genus, have probably evolved from unicellular bristles. Longitudinal dehiscence over the whole length of the thecae, which is present in many Thunbergia species, most likely evolved from short slits or pores as present in Pseudocalyx and Mendoncia.

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The sarracenioid families (Actinidiaceae, Roridulaceae, Sarraceniaceae) were rarely affiliated with other ericalean taxa in pre‐molecular classifications and have seldom been considered closely related to each other. In molecular phylogenetic studies, the sarracenioids form a strongly supported clade and are sister to the ericoid clade (Clethraceae, Cyrillaceae, Ericaceae); the sarracenioids and ericoids together make up core Ericales. To date, no phylogenetic study has included all sarracenioid genera (Actinidia, Clematoclethra and Saurauia in Actinidiaceae; Roridula in Roridulaceae; Darlingtonia, Heliamphora and Sarracenia in Sarraceniaceae). In particular, the monophyly of Saurauia has not previously been tested using molecular characters. We shed light on the phylogenetic relationships within the sarracenioid clade and, based on ancestral state reconstructions, test floral characters previously suggested as potential synapomorphies for the sarracenioids and ericoids. Phylogenetic analysis was performed for the DNA regions ITS, rbcL, rpl32‐trnL, trnK and trnL‐F using RAxML, MrBayes and PAUP*. Our results support the monophyly of the sarracenioid clade as well as of all its families and non‐monotypic genera. Two distinct geographical lineages are identified in Saurauia; the two lineages are characterised by differences in petal union (choripetaly versus sympetaly), style union (free versus partially united), gynoecium merism and base chromosome numbers. Our analyses identify the following floral characters as synapomorphic for core Ericales: adaxial anther attachment, anther inversion and a depression at the ovary‐to‐style transition. Proximally thick to massive petals, the presence of a nucellar hypostase in ovules and polystemony are synapomorphies of the sarracenioid clade. The presence of calcium oxalate raphides, mucilage cells, a secretory inner gynoecium surface and the absence of synlateral vasculature in the ovary are synapomorphies of the Actinidiaceae‐Roridulaceae clade. A two‐whorled androecium is a synapomorphy of the ericoid clade.

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Floral structure and development of 18 species of 7hunbev'a (Thunbergioideae s.L., Acanthaceac) were studied comparatively. The flowers of 7hunberga are highly diverse and show a wide range of pollination syndromes. In general they are large and showy. Their pollination apparatus is highly elaborate, floral organs are often synorganized, and floral architecture is complex. In contrast to the high diversity of the anthetic flowers, their bauplan is uniform and their early development shows no major differences, i.e. in all species studied, the calyx arises as a ring primordium, the corolla is 'late sympetalous', and petals and stamens are initiated more or less simultaneously. Some differences are found in further calyx development, where several developmental patterns are present. More significant differences arise only later during development and mainly concern the structures of the calyx, the anthers, the stigma, and corolla aestivation. In the anthetic flowers there are many special characters that are present in all or the majority of the species studied, e.g. the calyx is reduced, the corolla tube is subdivided into two compartments and the anthers lack an endothecium. The present results on development and morphology of the flowers of Thunberga are compatible with an earlier subdivision of the genus into eight subgenera.

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Ranunculaceae comprise ca. 2,500 species (ca. 55 genera) that display a broad range of floral diversity, particularly at the level of the perianth. Petals, when present, are often referred to as “elaborate” because they have a complex morphology. In addition, the petals usually produce and store nectar, which gives them a crucial functional role in the interaction with pollinators. Its morphological diversity and species richness make this family a particularly suitable model group for studying the evolution of complex morphologies. Our aims are (1) to reconstruct the ancestral form of the petal and evolutionary stages at the scale of Ranunculaceae, (2) to test the hypothesis that there are morphogenetic regions on the petal that are common to all species and that interspecific morphological diversity may be due to differences in the relative proportions of these regions during development. We scored and analyzed traits (descriptors) that characterize in detail the complexity of mature petal morphology in 32 genera. Furthermore, we described petal development using high resolution X-Ray computed tomography (HRX-CT) in six species with contrasting petal forms (Ficaria verna, Helleborus orientalis, Staphisagria picta, Aconitum napellus, Nigella damascena, Aquilegia vulgaris). Ancestral state reconstruction was performed using a robust and dated phylogeny of the family, allowing us to produce new hypotheses for petal evolution in Ranunculaceae. Our results suggest a flat ancestral petal with a short claw for the entire family and for the ancestors of all tribes except Adonideae. The elaborate petals that are present in different lineages have evolved independently, and similar morphologies are the result of convergent evolution.