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

Abstract

The genus Dendrokingstonia (Annonaceae) is taxonomically revised and palynologically studied. Three species are recognized, one of which, D. gardneri, is described as new to science. One new combination, D. acuminata, is made. The genus occurs from southern Thailand to Peninsular Malaysia and Sumatra. On the basis of macromorphology and pollen characters, it is considered to be related to Monocarpia. Both genera show a combination of macromorphological characters that is rare in the family, i.e. considerably enlarged stigmas, leaves with percurrent tertiary veins, a highly reduced number of carpels per flower and relatively large monocarps with a thick, hard wall. Scanning and transmission electron microscopy show that the pollen grains of Dendrokingstonia and Monocarpia are monosulcate monads with a columellate infratectum and a more or less bulging intine at the sulcus.

A new Annonaceae genus, Wuodendron, provides support for a post–boreotropical origin of the Asian–Neotropical disjunction in the tribe Miliuseae

“…Subpetiolar buds are rare in Annonaceae, and this represents the first such observation in the tribe Miliuseae, although similar buds have previously been recorded in Annona (Soler & Cuevas, 2009;Liu & al., 2016). Wuodendron resembles Meiogyne and Sapranthus in its eucamptodromous leaf venation; this feature is common in the tribe Miliuseae, as well as the closely related tribes Monocarpieae (Mols & Keßler, 2000) and Dendrokingstonieae (Chaowasku & al., 2012b). Eucamptodromous venation is therefore likely to be symplesiomorphic for all three genera, with brochidodromous venation the derived state in Desmopsis, Stenanona and Tridimeris.…”

<p class="HeadingRunIn"><strong>Characterization of <em>Hubera</em> (Annonaceae), a new genus segregated from <em>Polyalthia</em> and allied to <em>Miliusa</em></strong></p>

“…Species of groups B and C possess monosulcate pollen and were found to form a strongly supported clade (now transferred to Fenerivia) recovered outside Miliuseae , which is congruent with the phylogenetic results. Genera outside Miliuseae exhibit monosulcate pollen, whereas genera belonging to Miliuseae possess cryptoaperturate/disulculate pollen (Chaowasku et al 2012). Species of groups A, D, and E have cryptoaperturate pollen, and their membership in Hubera, which is a member of the Miliuseae, was thus not unexpected.…”

A new subfamilial and tribal classification of the pantropical flowering plant family Annonaceae informed by molecular phylogenetics

“…The inclusion of the genus Monocarpia in Miliuseae would have been possible from the perspective of monophyly; we prefer, however, to erect a new tribe for Monocarpia alone as this genus has never previously been included in Miliuseae (Mols & Keßler, 2003;Mols et al, 2004). Monocarpia furthermore lacks cryptoaperturate/ disulculate pollen, which is synapomorphic for Miliuseae as circumscribed here (Chaowasku, Keßler & van der Ham, 2012). Relationships among clades V, W and X are unresolved.…”

“…Dendrokingstonia Rauschert is placed in Malmeoideae even though we did not include it in our analyses. Analyses by Chaowasku et al . (2012) put it in this subfamily, in a moderately supported position sister to clade X (Fig.…”