Phylogeny and biogeography of Maianthemum (Asparagaceae: Nolinoideae) revisited with emphasis on its divergence pattern in SW China

doi:10.1016/j.pld.2021.02.001

Plant Diversity ›› 2021, Vol. 43 ›› Issue (02): 93-101.DOI: 10.1016/j.pld.2021.02.001

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Phylogeny and biogeography of Maianthemum (Asparagaceae: Nolinoideae) revisited with emphasis on its divergence pattern in SW China

Ran Meng^a, Ying Meng^a, Yong-Ping Yang^b,c, Ze-Long Nie^a

a Key Laboratory of Plant Resources Conservation and Utilization, College of Biological Resources and Environmental Sciences, Jishou University, Jishou 416000, Hunan, China
b Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
c Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China

Received:2020-07-19 Revised:2021-01-21 Online:2021-05-20 Published:2021-04-25
Contact: Ze-Long Nie
Supported by:
This study was supported by grants from Natural Sciences Foundation of China (31760055), Natural Sciences Foundation of Hunan Province (2019JJ40232 and 2019JJ40233), Comprehensive Scientific Investigation of Biodiversity from the Wuling Mountains (2014FY110100), the Hunan Provincial Innovation Foundation for Postgraduate (CX2018B724), and the John D. and Catherine T. MacArthur Foundation. We thank Drs. Jun Wen, David E. Boufford, Akiko Soejima, Jin Murata, Esteban Martinez, Ting-Shuang Yi, Chien-Ti Chao, Tao Deng, Yang Niu, Guang-Wan Hu for samples collection and Dr. Guang-Yan Wang for lab assistance. The authors also thank two anonymous reviewers for their helpful comments and suggestions.

Phylogeny and biogeography of Maianthemum (Asparagaceae: Nolinoideae) revisited with emphasis on its divergence pattern in SW China

Ran Meng^a, Ying Meng^a, Yong-Ping Yang^b,c, Ze-Long Nie^a

a Key Laboratory of Plant Resources Conservation and Utilization, College of Biological Resources and Environmental Sciences, Jishou University, Jishou 416000, Hunan, China
b Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla 666303, Yunnan, China
c Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, Yunnan, China

通讯作者: Ze-Long Nie
基金资助:
This study was supported by grants from Natural Sciences Foundation of China (31760055), Natural Sciences Foundation of Hunan Province (2019JJ40232 and 2019JJ40233), Comprehensive Scientific Investigation of Biodiversity from the Wuling Mountains (2014FY110100), the Hunan Provincial Innovation Foundation for Postgraduate (CX2018B724), and the John D. and Catherine T. MacArthur Foundation. We thank Drs. Jun Wen, David E. Boufford, Akiko Soejima, Jin Murata, Esteban Martinez, Ting-Shuang Yi, Chien-Ti Chao, Tao Deng, Yang Niu, Guang-Wan Hu for samples collection and Dr. Guang-Yan Wang for lab assistance. The authors also thank two anonymous reviewers for their helpful comments and suggestions.

Abstract

Abstract: Maianthemum is a genus with more than 35 species from the tribe Polygonateae (Asparagaceae), widely distributed between North to Central Americas and eastern Asiawithhigh diversity in the eastern Himalayas to the Hengduan Mountains of SW China. Although most species from SW China form a well-supported clade, phylogenetic relationships within this clade remain unclear. With a broad level of taxon sampling and an extensive character sampling from eight DNA regions, this study intends to revisit the phylogeny and biogeography of the genus to better understand the divergence patterns of species from SW China. Phylogenetic results suggested the monophyly of Maianthemum with recognition of nine strongly supported clades, but backbone relationships among these clades remained largely uncertain. For the SW China clade, individuals from the same species are grouped into different lineages. Our results revealed that the fast radiation of the SW China clade was occurred in the eastern Himalayas, followed by subsequent radiation in the Hengduan Mountains in the Pliocene. Intercontinental disjunctions of Maianthemum in the Northern Hemisphere appear to have occurred multiple times during the late Miocene to the Pliocene, likely resulted by a combination of both vicariance and long-distance dispersal events.

Key words: Biogeography, Eastern Asia, Hengduan mountains, Intercontinental disjunction, Maianthemum, North America

摘要： Maianthemum is a genus with more than 35 species from the tribe Polygonateae (Asparagaceae), widely distributed between North to Central Americas and eastern Asiawithhigh diversity in the eastern Himalayas to the Hengduan Mountains of SW China. Although most species from SW China form a well-supported clade, phylogenetic relationships within this clade remain unclear. With a broad level of taxon sampling and an extensive character sampling from eight DNA regions, this study intends to revisit the phylogeny and biogeography of the genus to better understand the divergence patterns of species from SW China. Phylogenetic results suggested the monophyly of Maianthemum with recognition of nine strongly supported clades, but backbone relationships among these clades remained largely uncertain. For the SW China clade, individuals from the same species are grouped into different lineages. Our results revealed that the fast radiation of the SW China clade was occurred in the eastern Himalayas, followed by subsequent radiation in the Hengduan Mountains in the Pliocene. Intercontinental disjunctions of Maianthemum in the Northern Hemisphere appear to have occurred multiple times during the late Miocene to the Pliocene, likely resulted by a combination of both vicariance and long-distance dispersal events.

关键词: Biogeography, Eastern Asia, Hengduan mountains, Intercontinental disjunction, Maianthemum, North America

Ran Meng, Ying Meng, Yong-Ping Yang, Ze-Long Nie. Phylogeny and biogeography of Maianthemum (Asparagaceae: Nolinoideae) revisited with emphasis on its divergence pattern in SW China[J]. Plant Diversity, 2021, 43(02): 93-101.

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Phylogeny and biogeography of Maianthemum (Asparagaceae: Nolinoideae) revisited with emphasis on its divergence pattern in SW China

Phylogeny and biogeography of Maianthemum (Asparagaceae: Nolinoideae) revisited with emphasis on its divergence pattern in SW China

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