Novel classification and biogeography of Leptolejeunea (Lejeuneaceae, Marchantiophyta) with implications for the origin and evolution of the Asian evergreen broad‐leaved forests. Issue 5 (1st September 2021)

• Record Type: Journal Article
• Authors: Shu, Lei; Jin, Xin‐Jie; Zhu, Rui‐Liang
• Is Part Of: Journal of systematics and evolution. Volume 60:Issue 5(2022)
• Page Start: 1199
• Page End: 1217
• Publication Date: 2021-09-01
• Subjects: ancestral state -- diversification rate -- molecular clock -- RASP -- Soella; Plants -- China -- Classification -- Periodicals; Plants -- Classification -- Periodicals; 580.12
• DOI: 10.1111/jse.12798
• Languages: English
• ISSNs: 1674-4918

Abstract

Abstract: Although recent molecular phylogenetic analyses have greatly improved our understanding of the classification of the large liverwort family Lejeuneaceae, the frequent incongruencies between morphology‐based taxonomy and molecular phylogeny have hindered our understanding of evolutionary diversification within the group. Here we focus on Leptolejeunea (Spruce) Steph., a pantropical epiphyllous genus in Lejeuneaceae with 40 species. Phylogenetic studies on the genus have been hampered by insufficient taxon sampling, leaving the deep phylogenetic relationships within this group unresolved. We present the most comprehensive phylogenetic analysis of the genus to date with sampling of over 80% of species, including the enigmatic Leptolejeunea spinistipula (Mizut.) X.L.He endemic to Borneo. Based on data from three molecular markers with representatives of Leptolejeunea and its allies, Leptolejeunea appeared to be monophyletic following the exclusion of L. spinistipula and its transfer to Soella R.L.Zhu, L.Shu, Qiong He & Y.M.Wei. A total‐evidence approach was taken to resolve the backbone phylogeny of Leptolejeunea and a first infrageneric classification of Leptolejeunea, including a new subgenus and three new sections, is proposed based on integrated molecular and morphological evidence. Reconstruction of the evolutionary history showed a wide ancestral area of Leptolejeunea during the Paleogene that arose in mainland Asia, followed by an accelerated speciation rate. Across the biogeographical history of Leptolejeunea, long‐distance dispersal had profound effects on population expansion. Our findings suggest that Australasia is a source of biodiversity of Asian evergreen broad‐leaved forests that have been established since the Oligocene and rose after the early Miocene. Abstract : RASP global ancestral area reconstruction on a Leptolejeunea phylogeny, following the best supported model DIVALIKE+j. The letter at each node signifies the biogeographical area that received the highest support for that node. The colors of each circle reflect the relative proportion of support each biogeographical area received for that node. Colors next to extant taxa indicate their current distribution. Directions (gray arrows) of long‐distance dispersal between areas are shown in the map. A′, B′, C′, and D′ show the Bayesian analysis of macroevolutionary mixtures (BAMM) speciation rates along each branch of the Leptolejeunea time‐calibrated tree. A′, Chronogram with branches colored according to speciation rate. Warmer colors represent faster speciation rate. The red circle denotes one significant increase of speciation rate in the best shift configuration ( f = 0.68). B′, Rate‐through‐time plots of extinction rate for Leptolejeunea . C′, Rate‐through‐time plots of speciation for clade i + ii + iii in the green curved line, and for all Leptolejeunea in red. D′, Rate‐through‐time plots of speciation for clade iv + v + vi + vii in the blue curved line, and for all Leptolejeunea in red. Map source, DIVA‐GIS (http://www.diva-gis.org/ ) with modification.