A tropical lotus from the middle Miocene tropical rainforest flora of South China
Abstract
We report a new species of Nelumbo including all leaves, receptacles, fruits, and rhizomes from the Fotan flora, namely Nelumbo fujianensis sp. nov. from the middle Miocene Fotan Group of Fujian, South China. The new species comprises centrally peltate leaves with 20-30 actinodromous primary veins and a central disc, ca. 25-40 fruits embedded in a receptacle, along with abundant rhizomes without tubers. Based on the lack of rhizome tubers, N. fujianensis sp. nov. resembles the tropical form of Nelumbo nucifera, which is growing in rainforests from India, Thailand, Indonesia, and northern Australia. Megafossils of tropical lotus are here reported for the first time from the middle Miocene strata of South China. These data, together with earlier records of temperate Nelumbo in the middle and late Eocene strata, strongly suggest that evergreen and deciduous forms of N. nucifera were diversified by the middle Miocene. Our finding in this study combining genotypes evidence show earlier species differentiation of extant species, and indicated the intercontinental disjunction of the genus may have an older age, probably earlier than the middle Miocene. By analyzing the results from geographical range expansion, and ecological niche of tropical lotus, we infer that the Fotan region had a long day length during the middle Miocene.
- Publication:
-
Review of Palaeobotany and Palynology
- Pub Date:
- April 2022
- DOI:
- 10.1016/j.revpalbo.2022.104611
- Bibcode:
- 2022RPaPa.29904611D
- Keywords:
-
- Divergence times;
- Tropical lotus;
- Nelumbo;
- Tropical rainforest;
- South China