Supplementary Table 1.List of 51 unambiguous molecular synapomorphies supporting pleuronectiform monophyly.The list was extracted from PAUP* using the topology obtained under maximum parsimony in TNT. Character number refers to the position in the concatenated alignment (available from Dryad).

Marker / Character / Consistency Index / Transformation
16S / 95 / 0.125 / A ==> G
16S / 485 / 0.077 / C ==> A
16S / 520 / 0.097 / A ==> C
16S / 570 / 0.107 / T ==> C
EGR1 / 2109 / 0.214 / T ==> C
EGR2B / 3069 / 0.5 / C ==> A
EGR2B / 3072 / 0.091 / T ==> C
EGR3 / 3342 / 0.375 / G ==> A
EHHADH / 4473 / 0.158 / C ==> T
GCS1 / 5064 / 0.2 / A ==> G
GCS1 / 6063 / 0.15 / C ==> T
IRBP / 7291 / 0.286 / T ==> A
MLL / 9583 / 0.231 / A ==> G
MYH6 / 9696 / 0.1 / G ==> A
MYH6 / 9828 / 0.143 / A ==> G
PLAGL2 / 10629 / 0.143 / T ==> C
PLAGL2 / 10648 / 0.143 / G ==> A
PLAGL2 / 10699 / 0.333 / C ==> A
RAG1 / 11553 / 0.2 / C ==> T
RAG1 / 11622 / 0.2 / A ==> G
RAG1 / 11868 / 0.12 / C ==> T
RAG1 / 11907 / 0.13 / G ==> A
RAG1 / 11958 / 0.273 / G ==> A
RAG1 / 12461 / 0.333 / G ==> A
RH / 13051 / 0.214 / G ==> A
RH / 13230 / 0.091 / G ==> A
RH / 13268 / 0.067 / T ==> C
RH / 13374 / 0.091 / G ==> A
RH / 13404 / 0.133 / C ==> T
RIPK4 / 14185 / 0.167 / G ==> A
RNF213 / 14304 / 0.5 / C ==> T
RNF213 / 14763 / 0.125 / C ==> T
RNF213 / 14784 / 0.13 / A ==> G
RNF213 / 14958 / 0.5 / C ==> T
SH3PX3 / 15702 / 0.333 / T ==> C
Sidkey / 16824 / 0.118 / G ==> A
Sidkey / 17286 / 0.2 / A ==> C
Sidkey / 17370 / 0.125 / T ==> C
Sidkey / 17406 / 0.125 / T ==> C
Sidkey / 17497 / 0.111 / T ==> C
Sidkey / 17523 / 0.083 / T ==> C
Sidkey / 17631 / 0.158 / A ==> G
Sidkey / 17667 / 0.167 / T ==> C
Sidkey / 17694 / 0.231 / T ==> C
Sidkey / 17826 / 0.059 / T ==> C
UBE3A / 17940 / 0.429 / A ==> T
UBE3A / 18414 / 0.188 / T ==> C
UBE3A / 18459 / 0.214 / C ==> T
ZNF503 / 20529 / 0.2 / C ==> G
ZNF536 / 21183 / 0.105 / A ==> G
ZNF536 / 21830 / 0.333 / T ==> C