Phylogenetic relationships among the ciliate arthrodontous mosses: evidence from chloroplast and nuclear DNA sequences

Parsimony and maximum likelihood analyses of combined trnL (UAA) 5' exon - trnF (GAA) and rps4 exon cpDNA, and 18S nrDNA sequences of 60 arthrodontous moss taxa indicate strong support for the monophyly of a clade containing the Splachnineae, Orthotrichineae, and diplolepideous alternate sub-orders. A clade including the Splachnineae, Meesiaceae and Leptobryum (Bryaceae) i s similarly well supported and forms the sister group to a clade comprising the Orthotrichineae and the other diplolepideous alternate mosses. Within this latter clade a number of well supported lineages are identified, but r elationships among these remain poorly resolved. These analyses indicate th at the Splachnaceous and Orthotrichaceous peristomes have been independentl y derived from an ancestral 'perfect' bryoid peristome.