Generic delimitation and historical biogeography in the early‐divergent 'ambavioid' lineage of Annonaceae: Cananga, Cyathocalyx and Drepananthus

Abstract

Generic delimitation of Cyathocalyx and Drepananthus has been controversial, with some authors recognizing them as distinct genera, and others recognizing a more broadly defined Cyathocalyx, inclusive of Drepananthus. Some doubt also exists regarding the relationships between these taxa and Cananga. Molecular phylogenetic analyses are presented based on combined psbA‐trnH spacer, trnL‐F, matK and rbcL sequences. Results indicate that Cananga, Cyathocalyx s.str. and Drepananthus form three generally well‐supported clades, although with inadequate resolution of relationships among the three clades. Morphological variation is re‐evaluated, and the narrower delimitation of Cyathocalyx proposed, necessitating 21 new nomenclatural combinations following the recognition of Drepananthus as a distinct genus. Divergence times are estimated using an uncorrelated lognormal distributed (UCLD) relaxed molecular clock. Historical biogeographical analysis suggests that the ambavioid lineage originated in Africa, with subsequent dispersal into Asia. Alternative hypotheses for this dispersal, involving rafting on the Indian tectonic plate versus migration via the extensive boreotropical forests associated with the Eocene thermal maximum, are evaluated, and the latter route identified as the most consistent with the divergence age estimates and the geological and palaeoclimatic data.

A taxonomic revision and pollen morphology of the genus Dendrokingstonia (Annonaceae)

“…ex Hook.f. & Thomson s.s. (van der Heijden & Keßler, 1990; Surveswaran et al ., 2010). Cyathocalyx s.s. also has greatly enlarged stigmas (van Heusden, 1992).…”

Molecular Phylogenetic Support for the Taxonomic Merger of <I>Fitzalania</I> and <I>Meiogyne</I> (Annonaceae): New Nomenclatural Combinations Under the Conserved Name <I>Meiogyne</I>

“…The four chloroplast DNA regions, matK, rbcL, trnL-F and ndhF, were sequenced using the following primers for amplification: (1) matK gene: primers matK-13F/515R, matK-424F/788R, and matK-449F/824R (Su et al 2008); (2) rbcL gene: primers rbcL-7F/429R, rbcL-127F/734R, rbcL-656F/ 1100R, and rbcL-984F/1381R (Su et al 2008); (3) trnL-F (trnL intron and trnL-trnF intergenic spacer): primers trnLF-12F/433R, trnLF-147F/580R, trnLF-413F/774R, and trnLF-597F/960R (Su et al 2008) or trnLF-12F/556R and trnLF-500F/960R (Surveswaran et al 2010); and (4) ndhF gene: primers ndhF-1F/581R, ndhF-451F/972R, ndhF-561F/1025R, ndhF-972F/1321R, ndhF-1216F/1621R, and ndhF-1598F/2210R .…”

The diversity and evolution of pollination systems in Annonaceae

“…There is no published information on the reproductive biology of either Cyathocalyx or Drepananthus (treated here as distinct genera, following proposals by Surveswaran et al ., 2010), other than a casual observation by Corner (1988: 136) that the flowers of some Drepananthus spp. (cited under the generic name Cyathocalyx ) are visited by beetles.…”