Mucuna is a pantropical genus. This has 105 extant species of climbing lianas and shrubs in the legume family. It is the third-largest family of flowering plants. The genus Mucuna is represented in modern tropical regions. But fossil records of this genus are limited and poorly studied.
A research paper has been published in Review of Palaeobotany and Palynology. Xishuangbanna Tropical Botanical Garden (XTBG) of the Chinese Academy of Sciences and the Vietnam Academy of Science and Technology researchers have presented the newly-discovered fossil pods in one specimen from the late Miocene of the Yen Bai Basin.
The fossil specimen has linear-oblong, compressed and slightly curved pods which have at least three to five seeds, a pair of thickened marginal wings and an apex with a cone-shaped beak. extensive morphological observation and comparison of the morphology, the scientists assigned the fossil pods to the genus Mucuna.
These fossil pods are morphologically similar to a living species in Mucuna subgenus Macrocarpa. The name of this species is M. birdwoodiana and this is also endemic to China. So, this indicates a similar habitat along the Red River valley in the late Miocene.
Scientists think the fossil pods from northern Vietnam are the first convincing macrofossil record for this genus.
Mucuna is widely distributed in northern Vietnam. This suggests Mucuna has existed in this region since the late Miocene.