Menispermaceae and the diversification of tropical rainforests near the Cretaceous–Paleogene boundary

Abstract

Summary Modern tropical rainforests have the highest biodiversity of terrestrial biomes and are restricted to three low‐latitude areas. However, the actual timeframe during which tropical rainforests began to appear on a global scale has been intensely disputed. Here, we used the moonseed family (Menispermaceae), an important physiognomic and structural component of tropical rainforests on a worldwide basis, to obtain new insights into the diversification of this biome. We integrated phylogenetic, biogeographic and molecular dating methods to analyse temporal and spatial patterns of global diversification in Menispermaceae. Importantly, a burst of moonseed diversification occurred in a narrow window of time, which coincides with the Cretaceous–Paleogene (K–Pg) boundary. Our data also suggest multiple independent migrations from a putative ancestral area of Indo‐Malay into other tropical regions. Our data for Menispermaceae suggest that modern tropical rainforests may have appeared almost synchronously throughout the three major tropical land areas close to, or immediately following, the K–Pg mass extinction.

Tropical rain forest evolution: palms as a model group

“…The implication of these results is that tropical rain forest, or at least a tropical rain forest-like biome, existed at northern latitudes in Laurasia in the mid-Cretaceous, a controversial finding because the most widely accepted fossil evidence for the earliest tropical rain forest is post-Cretaceous, dating from the Palaeocene (55 to 65 Ma) within its current equatorial range [20,21]. Though our inferences may be met with scepticism, they are consistent with limited evidence of tropical rain forest-like fossil floras in the mid-Cretaceous of North America [22], as well as indirect evidence from molecular dating of other important major tropical lineages [16,17,23]. While mid-Cretaceous Laurasia may not have supported modern tropical rain forest as we know it today in terms of composition and diversity, the evolutionary histories captured in multiple tropical rain forest-restricted lineages suggest that the tropical rain forest biome, or something very close to it, originated well before the end of the Cretaceous (65 Ma).…”

Molecular phylogenetics and biogeography of the mint tribe Elsholtzieae (Nepetoideae, Lamiaceae), with an emphasis on its diversification in East Asia

“…This incongruence is most likely due to their incomplete taxon sampling within the tribe Elsholtzieae by previous authors (only one Elsholtzia and one Collinsonia species were sampled). Curiously, the origin and early differentiation of Nepetoideae (the largest subfamily of Lamiaceae) corresponds in age with studies of a few other plant lineages, including epiphytic ferns 40 and Menispermaceae 41 . Our refined time estimates and ancestral area reconstruction are important because they suggest an East Asian origin of the tribe Elsholtzieae at around 50.1 Ma, followed by subsequent and rapid diversification into all the major clades between 43–41 Ma (Figs 2, 3).…”

A new species of Cissampelos (Menispermaceae) from Bolivia and Paraguay

“…ex Wight, were placed in subtribe Cissampelinae, one of the three subtribes in tribe Menispermeae, which together with seven other tribes were recognized by Diels (1910) in the family Menispermaceae. In studies based on ndhF , matK , trnL-F , ITS , rbcL , and atpB sequence data, subtribe Cissampelinae has been consistently recovered as monophyletic (Ortiz et al 2007, Wang et al 2007, Hoot et al 2009, Jacques et al 2011, Wang et al 2012), although relationships within the subtribe remain unresolved (Jacques et al 2011). The sampled species of Cissampelos form a clade that is sister to Cyclea (Ortiz et al 2007, Wang et al 2012, Ortiz et al in prep.…”

“…In studies based on ndhF , matK , trnL-F , ITS , rbcL , and atpB sequence data, subtribe Cissampelinae has been consistently recovered as monophyletic (Ortiz et al 2007, Wang et al 2007, Hoot et al 2009, Jacques et al 2011, Wang et al 2012), although relationships within the subtribe remain unresolved (Jacques et al 2011). The sampled species of Cissampelos form a clade that is sister to Cyclea (Ortiz et al 2007, Wang et al 2012, Ortiz et al in prep. ), but studies including the southern African Cissampelos capensis L. f. recovered a polyphyletic Cissampelos , with Cyclea (Hoot et al 2009, Jacques et al 2011), and Antizoma (Jacques et al 2011) nested within.…”