Geographical structure, narrow species ranges, and Cenozoic diversification in a pantropical clade of epiphyllous leafy liverworts

Abstract

The evolutionary history and classification of epiphyllous cryptogams are still poorly known. Leptolejeunea is a largely epiphyllous pantropical liverwort genus with about 25 species characterized by deeply bilobed underleaves, elliptic to narrowly obovate leaf lobes, the presence of ocelli, and vegetative reproduction by cladia. Sequences of three chloroplast regions (rbcL, trnL‐F, psbA) and the nuclear ribosomal ITS region were obtained for 66 accessions of Leptolejeunea and six outgroup species to explore the phylogeny, divergence times, and ancestral areas of this genus. The phylogeny was estimated using maximum‐likelihood and Bayesian inference approaches, and divergence times were estimated with a Bayesian relaxed clock method. Leptolejeunea likely originated in Asia or the Neotropics within a time interval from the Early Eocene to the Late Cretaceous (67.9 Ma, 95% highest posterior density [HPD]: 47.9–93.7). Diversification of the crown group initiated in the Eocene or early Oligocene (38.4 Ma, 95% HPD: 27.2–52.6). Most species clades were established in the Miocene. Leptolejeunea epiphylla and L. schiffneri originated in Asia and colonized African islands during the Plio‐Pleistocene. Accessions of supposedly pantropical species are placed in different main clades. Several monophyletic morphospecies exhibit considerable sequence variation related to a geographical pattern. The clear geographic structure of the Leptolejeunea crown group points to evolutionary processes including rare long‐distance dispersal and subsequent speciation. Leptolejeunea may have benefitted from the large‐scale distribution of humid tropical angiosperm forests in the Eocene.

A Burmese amber fossil of <i>Radula</i> (Porellales, Jungermanniopsida) provides insights into the Cretaceous evolution of epiphytic lineages of leafy liverworts

“…Similar topologies suggestive of the same pattern have been reconstructed in other Porellales genera such as Leptolejeunea (Spruce) Steph. (Bechteler et al, 2017), Lejeunea Lib. and Microlejeunea (Spruce) Steph.…”

Species richness and composition of epiphytic bryophytes in flooded forests of Caxiuanã National Forest, Eastern Amazon, Brazil

“…This has been a frequent result in studies with bryophytes performed in tropical forests in South America (Cornelissen and Gradstein 1990, Acebey et al 2003, Gradstein and Costa 2003, Campelo and Pôrto 2007, Mota-deOliveira et al 2009, Brito and Ilkiu-Borges 2014, Garcia et al 2014, Pantoja et al 2015, Oliveira and Mota-de-Oliveira 2016. This family experienced recent periods of rapid diversification coinciding with the rise of the angiosperms in the Cretaceous (Feldberg et al 2014, Bechteler et al 2016, providing a wide morphological variation that allows them to develop in different environments, especially in tropical forests representing up to 70% of the bryoflora (Gradstein 1979, 1994, 1997, Gradstein et al 2001. Calymperaceae and Sematophyllaceae appear as most predominant among moss families in tropical rainforests, which coincide with the statement of Gradstein et al (2001), and corroborate with further results from studies performed in the Amazon region (Lisboa et al 1998, 1999, Santos and Lisboa 2003, Mota-de-Oliveira et al 2009, Mota-de-Oliveira and ter Steege 2013, Brito and Ilkiu-Borges 2014, Garcia et al 2014, TavaresMartins et al 2014, Pantoja et al 2015.…”

Multiple Geographical Origins of Environmental Sex Determination enhanced the diversification of Darwin’s Favourite Orchids

“…Cyrtopodiinae, Dipodiinae, Eulophiinae, and Oncidiinae). Genomic DNA extraction, amplification, sequencing and alignment procedures are the same as in Irimia et al 65 , Pérez-Escobar et al 14 , and Bechteler et al 66 . For the newly sampled taxa, we sequenced nuclear ribosomal external and internal transcribed spacers (ETS and ITS, respectively), a fragment of the Xdh gene, and also a ~1500 bp fragment of the plastid gene ycf 1, and the trn S– trn G intergenic spacer.…”