| Diversity of flowers in Apocynaceae. (A) Aspidosperma pyrifolium, Aspidospermateae; (B) Hancornia speciosa, Willughbeieae; (C) Couma rigida, Willughbeieae; (D) Tabernaemontana solanifolia, Tabernaemontaneae; (E) Condylocarpon isthmicum, Alyxieae; (F) Thevetia peruviana, Plumerieae; (G) Allamanda puberula, Plumerieae, (H) Wrightia coccinea, Wrightieae; (I) Adenium obesum, Nerieae; (J) Mandevilla atroviolacea, Mesechiteae; (K) Pentopetia grevei, Periplocoideae; (L) Secamone parviflora, Secamonoideae; (M) Ceropegia tihamana, Ceropegieae; (N) Orbea lutea, Ceropegieae; (O) Calotropis procera, Asclepiadinae; (P) Oxypetalum rusticum, Oxypetalinae [Photos of panels (A-G,I,J,O,P) by Rapini; panels (H,K-N) by Meve].

Contexts in source publication

Context 1

... comprises large trees, treelets, shrubs, lianas (twining woody climbers), and more rarely epiphytes in tropical rainforests, succulents in dry, open landscapes, perennial herbs in temperate grasslands, to vines (herbaceous or succulent twiners) in a wide variety of habitats. The flowers are usually pentamerous (tetramerous in Leuconotis, and calyx tetramerous in Parahancornia and a few species of Aspidosperma), isostemonous, bicarpellate (tri-to pentacarpellate in Lepinia, Lepiniopsis, and some species of Pleiocarpa), and hyperdiverse in size and corolla shape (Figure 1), ranging from reflexed (e.g., Asclepias) or rotate, star-like (e.g., Stapelia) to campanulate (e.g., Beaumontia and Mandevilla), urceolate (e.g., Urceola and Dischidia), salverform (e.g., Carissa and Tabernaemontana), cylindrical pitfalls (Ceropegia), or even figlike (Heterostemma ficoides A. Kidyoo;Kidyoo, 2019). They often produce corolline and/or staminal coronas and show a spectrum of integration between anthers and style-head that culminated with the formation of a gynostegium and five pollinaria, formed by a translator derived from gynoecium exudates and pollinia from the androecium (Endress, 2016;Endress et al., 2018Endress et al., -2019. ...

Context 2

... created a default model (M1), which allowed unconstrained and time homogeneous dispersal probabilities, and set the maximum number of areas to four (the maximum inhabited by extant species). To model shifts in dispersal probabilities over time due to plate movements, changing sea levels, and other major geological processes, we then defined a time-stratified model (M2) with four time periods (time slices: 0-30, 30-60, 60-80, 80-100 Ma; for details, see Supplementary Methods 1 and Supplementary Figure 1. N.B., the M2 model also restricts most dispersals between Hemispheres and is intended to illuminate the importance of such interhemispheric dispersal pathways in the biogeographic history of Apocynaceae). ...

Context 3

... we used Bayesian analysis of macroevolutionary mixture (BAMM 2.5; Rabosky, 2014) to reconstruct the positions of significant shifts in diversification regimes during the evolution of Apocynaceae. Sampling fractions per clade were provided in order to account for uneven representation of species that are included in the tree (Supplementary Table 1). Appropriate priors were estimated in BAMMtools v2.1.7 ( Rabosky et al., 2014) and a series of different priors on the expected number of shifts were tested in preliminary analyses (0.1-12; because results were stable among tested priors, we show and discuss results using a shift prior of 1; for comparison of the prior and posterior distributions of number of shifts, see Supplementary Figure 6). ...

Context 4

... pollinia-bearing lineages emerged in Africa, independently derived from the apocynoid ancient radiation ( Straub et al., 2014), although they formed a clade in the Apocynaceae tree used here (Fishbein et al., 2018; Figures 3, 4). Livshultz et al. (2011) hypothesized that the more efficient pollination mechanism conferred by pollinia contributed to reduce the Allee effects caused by low population densities and fewer pollinators available in cooler and seasonally dry forests in Africa after the early Eocene climatic optimum (Jacobs, 2004). ...