Programs and options The following program versions and options were used: ClustalW : version 1.83[27] default: -type=dna -align gap-opt: -type=dna -align -pwgapopen=GO -gapopen=GO -pwgapext=GE -gapext=GE subst-mat.: -type=dna -align -dnamatrix=MATRIX -pwdnamatrix=MATRIX MAFFT : version 5.667[25] default: fftns default: ginsi old: fftns --op 0.51 --ep 0.041 old: ginsi --op 0.51 --ep 0.041 MUSCLE : version 3.6[16,26] -seqtype rna PCMA : version 2.0[49] POA : version 2[50] -do_global -do_progressive MATRIX prank : version 270705b – 1508b[29] -gaprate=GR -gapext=GE ProAlign : version 0.5a3[51] java -Xmx256m -bwidth = 400 -jar ProAlign_0.5a3.jar ProbConsRNA : version 1.10[33] Prrn : version 3.0 (package scc)[52]