Table 1. Taxa list for this study.

Subgenus a	Section b	Species	DNA bank number or living collection number
Cymbidium	Austrocymbidium	Cymbidium madidum	O-1472
	Bigibbarium	Cymbidium devonianum	*
	Cymbidium	Cymbidium atropurpureum	O-1465
	Cymbidium	Cymbidium finlaysonianum	1954–41302 BEAK
	Floribundum	Cymbidium floribundum	O-1461
	Floribundum	Cymbidium pumilum	O-1469
	Floribundum	Cymbidium suavissimum	O-1467
	Himantophyllum	Cymbidium dayanum	O-1468
Cyperorchis	Annamaea	Cymbidium erythrostylum	O-1471
	Cyperorchis	Cymbidium eburneum	O-1505
	Cyperorchis	Cymbidium elegans	O-1479
	Cyperorchis	C. eburneum x C. hookerianum	O-1481
	Cyperorchis	Cymbidium erythraeum	O-1463
	Cyperorchis	Cymbidium giganteum	O-69
	Cyperorchis	Cymbidium hookerianum	O-1466
	Cyperorchis	Cymbidium insigne	O-1475
	Cyperorchis	Cymbidium iridioides	O-1462
	Cyperorchis	Cymbidium lowianum	O-1476
	Cyperorchis	Cymbidium mastersii	O-1506
	Cyperorchis	Cymbidium sanderae	O-1470
	Cyperorchis	Cymbidium whiteae	O-1473
	Parishiella	Cymbidium tigrinum	17717
Jensoa	Jensoa	Cymbidium ensifolium c	O-1478
	Jensoa	Cymbidium goeringii	O-1477
	Jensoa	Cymbidium kanran c	O-1499
	Jensoa	Cymbidium lancifolium c	O-293
	Jensoa	Cymbidium sinense c	O-1503
Outgroup		Acriopsis sp.	9060
		Grammatophyllum speciosum	1983–2947 BACR 450
		Thecostele secunda	O-406

^a: Subgeneric delimitation of Cymbidium is based on Du Puy and Cribb [50]

^b: Sectional delimitation of Cymbidium is based on Du Puy and Cribb [50]

^c: The plastome sequence of these species have been reported by Yang et al. [43] and directly submitted by Kim et al. in NCBI. Therefore, these four species are used for confirming the location of ndh genes to mitochondrial genome.

*: Only fresh leaves were collected from Ratcliffe Orchids, Ltd. (Hampshire, UK)