Table 2.

Fossils supporting each of the node calibrations and the prior distributions selected for the Bayesian time divergence analysis. Node numbers are depicted in Fig. 1

Node/TAXA	Fossil Classification and estimated ages	Type Locality/PaleoDB	Prior distribution
Root	Odonata, Zygoptera, Eosagrionidae, Eosagrion risi †, Early Jurassic, Toarcian, 183–182 Ma (Handlirsch, 1920)	Germany/ Dobbertin, Mecklenburg PaleoDB 123,987	Uniform prior distribution max = 183 min = 47.8
Calopterygoidea	Odonata, Zygoptera, Calopterygoidea, Calopterygidae Sinocalopteryx shanyongensis †, Eocene, Ypresian (56–47.8 Ma) NIGP 151367 (Lin et al., 2010) Odonata, Zygoptera, Epallagidae, Labandeiraia europae †, Eocene, Ypresian (56–47.8 Ma) Odonata, Zygoptera, Epallagidae, Ejerslevia haraldi †, Eocene, Ypresian (56–47.8 Ma) (Zessin, 2011)	Yunnan, China PaleoDB 113,892 Island of Fur, Denmark PaleoDB 123,998, 127,173 Ejerslev, Mors, Denmark PaleoDB 157,041
Outgroup Euphaeidae	Odonata, Zygoptera, Epallagidae, Labandeiraia americaborealis †, Eocene, Bridgerian (50–46.2 Ma) 31.665A-B (Petrulevicius et al., 2007) Odonata, Zygoptera, Epallagidae, Litheuphaea coloradensis †, Eocene, Bridgerian (50–46.2 Ma) BMNH Pl II 562 (Petrulevicius et al., 2007) Odonata, Zygoptera, Epallagidae, Eodichroma mirifica †, Late/Upper Eocene, (37.2–33.9) (Cockerell 1923) Odonata, Zygoptera, Epallagidae, Litheuphaea ludwigi †, Eocene, Priabonian (38–33.9 Ma) (Bechly,1990) Odonata, Zygoptera, Epallagidae, Elektroeuphaea flecki †, Eocene, Priabonian (38–33.9 Ma) (Nel et al., 2013) Odonata, Zygoptera, Epallagidae, Parazacallites aquisextanea †, Oligocene, Chattian (28.1–23.03 Ma) MNHN IPM-R.06688 (Nel, 1988)	Colorado, USA PaleoDB = 107,337 Colorado, USA PaleoDB = 107,337 Texas, USA PaleoDB = 130,390 Baltic Amber, Russian Federation PaleoDB = 123,911 Baltic Amber, Poland PaleoDB = 123,215 Bouches-Du-Rhone, France PaleoDB 123,943	LogNormal; mean = 50; std. = 0.15
Ingroup/ Polythoridae	Odonata, Zygoptera, Polythoroidea, Bolcathore colorata †, Eocene, Lutetian (47.8–41.3 Ma) MCSNV I.G. 37,582 (Gentilini, 2002) Odonata, Zygoptera, Polythoroidea, Bolcathore sp. †, Eocene, Priabonian (38–33.9 Ma) MCSNV I.G. 37,582 (Nel and Fleck, 2014) Odonata, Zygoptera, Protothore explicata †, Eocene, Bartonian (41.3–38 Ma) (Cockrell, 1930)	Pesciara di Bolca, Italy PaleoDB = 122,230 Isle of Wight, United Kingdom PaleoDB = 123,960 California, USA PaleoDB = 117,537	Uniform prior distribution max = 48 min = 33.9