Comparative plastomes analysis reveals the first infrageneric evolutionary hotspots of orthotrichum s.l. (Orthotrichaceae, Bryophyta)

Abstract

Plastomes serve as the main resources in the study of plant phylogeny, phylogeography, and barcode development. To date, only 5 complete plastomes of acrocarpous mosses are known. This study analyzes the complete plastome sequence of 5 mosses from Orthotrichaceae: Nyholmiella obtusifolia (Brid.) Holmen & E. Warncke; Orthotrichum rogeri Brid.; Stoneobryum bunyaense D.H. Norris & H. Rob.; Lewinskya incana F. Lara, Garilleti & Goffinet; and Ulota bruchii Hornsch. The plastomes of all studied species are similar in length (ca. 123 kbp) and have a quadripartite structure with 118 unique genes. A total of 278 simple sequence repeats were found, and the mononucleotide repeats were the most abundant. Dinucleotide, trinucleotide, and tetranucleotide repeats were also observed. Tandem repeats were observed in all studied genomes in similar amounts. A total of 6331 single nucleotide polymorphisms and 779 indels were found in the analyzed genomes. The most variable spacer was located between rpl14 and rps8 (π = 0.366), and matK (π = 0.046) was the most variable of the genes. Phylogenetic reconstruction based on protein coding sequences confirmed the recent division of the tribe.