­Phylogenetic Analysis of the Genus Pohlia (Bryophyta, Bryaceae) Using Chloroplast and Nuclear Ribosomal DNA

Abstract

The genus Pohlia Hedwig is a large moss genus that has been placed in the Bryaceae family as traditionally determined. However, a molecular phylogenetic analysis has indicated that the Pohlia genus is more closely related to genera that are traditionally classified into the Mniaceae or Mielichhoferiaceae families. In this study, we performed a molecular phylogenetic analysis using evidence from four chloroplast regions (atpB-rbcL, rps4, trnG, and trnL-trnF) and one nuclear ribosomal intragenic spacer region (ITS) using different methods (maximum parsimony, maximum likelihood, and Bayesian inference). The phylogenetic relationships between Pohlia and its related genera are discussed. Two large clades among our samples were well supported in all of the datasets. The traditionally defined Bryaceae species, including Brachymenium pendulum, Bryum caespiticium, Bryum capillare, Anomobryum gemmigerum, and Rhodobryum ontariense, formed a monophyletic clade with high support. The second clade corresponding to the Mielichhoferiaceae-Mniaceae complex also had high support. All of the Pohlia, Mielichhoferia and Mniaceae samples were included in this latter clade. The clearest result from the phylogenetic analysis is that the Pohlia genus is non-monophyletic. The analysis is identical when using three methods and concludes that Pohlia is closer to the genera in Mielichhoferiaceae and Mniaceae. A formal taxonomic treatment of this clade was not performed because we lacked sufficient specimens of the species, although this work will be included in a future study.

The complete chloroplast genome of Mnium marginatum (With.) P. Beauv.

“…These genera were transferred to Mniaceae from family Bryaceae and Mielichhoferiaceae (Buck and Goffinet 2000;Frey and Stech 2009). And these changes were supported by studies based on molecular data (Cox et al 2014;Guerra et al 2011;Niu et al 2018). Thus, Mniaceae became the largest family of order Bryales.…”

The complete chloroplast genome sequence of Pohlia cruda (Hedw.) Lindb.

“… 2014 ; Niu et al. 2018 ) showed that Pohlia was more closely related to Mniaceae than to Bryaceae and supported the transfer of Pohlia to Mniaceae. Shaw ( 2009 ) noted that there were distinct morphological differences among species of Mniaceae, such as species in the genera Pohlia , Mielichhoferia , and Mnium .…”

“…Brotherus (1903) placed Pohlia in Bryaceae based on morphological characteristics. However, the results based on chloroplast genome fragment sequences (Goffinet et al 2001;Cox et al 2014;Niu et al 2018) showed that Pohlia was more closely related to Mniaceae than to Bryaceae and supported the transfer of Pohlia to Mniaceae. Shaw (2009) noted that there were distinct morphological differences among species of Mniaceae, such as species in the genera Pohlia, Mielichhoferia, and Mnium.…”

“…Bryales is one of the most important groups of globally distributed mosses (Guerra et al 2011). However, the phylogenetic relationships among the families in Bryales have been controversial for the past few years (Goffinet et al 2001;Niu et al 2018). The controversy was mainly in the clade of Mniaceae-Mielichhoferiaceae, especially in the systematic position of the genus Pohlia.…”

“… 2001 ; Niu et al. 2018 ). The controversy was mainly in the clade of Mniaceae-Mielichhoferiaceae, especially in the systematic position of the genus Pohlia .…”