Table 1.

Nucleotide composition bias of all spider mitogenomes available from GenBank and an outgroup species used in phylogenetic analysis.

Order	Family	Species	Length (bp)	AT-skew	GC-skew	Accession number
Araneae	Tetragnathidae	Tetragnatha maxillosa	14578	-0.087	0.246	KP306789
	Tetragnathidae	Tetragnatha nitens	14639	-0.055	0.200	KP306790
	Araneidae	Argiope amoena	14121	-0.060	0.241	NC_024281*
	Araneidae	Argiope bruennichi	14063	-0.035	0.263	NC_010596*
	Araneidae	Araneus ventricosus	14617	-0.048	0.243	NC_025634*
	Araneidae	Neoscona theisi	14156	-0.059	0.252	NC_026290*
	Salticidae	Habronattus oregonensis	14381	-0.112	0.301	NC_005942*
	Salticidae	Telamonia vlijmi	14601	-0.081	0.235	NC_024287*
	Salticidae	Plexippus paykull	14316	-0.105	0.318	NC_024877*
	Lycosidae	Pirata subpiraticus	14528	-0.111	0.295	NC_025523*
	Lycosidae	Pardosa laura	14513	-0.109	0.285	NC_025223*
	Lycosidae	Wadicosa fidelis	14741	-0.130	0.312	NC_026123*
	Pholcidae	Pholcus sp.	14279	-0.188	0.372	NC_010775*
	Pholcidae	Pholcus phalangioides	14459	-0.191	0.371	NC_020324*
	Dipluridae	Phyxioschema suthepium	13931	-0.040	0.472	NC_020322*
	Hypochilidae	Hypochilus thorelli	13991	-0.140	0.266	NC_010777*
	Nemesiidae	Calisoga longitarsis	14070	-0.146	0.365	NC_010780*
	Nephilidae	Nephila clavata	14436	-0.053	0.242	NC_008063*
	Theraphosidae	Ornithoctonus huwena	13874	-0.083	0.344	NC_005925*
	Selenopidae	Selenops bursarius	14272	-0.123	0.321	NC_024878*
	Oxyopidae	Oxyopes sertatus	14442	-0.130	0.321	NC_025224*
	Liphistiidae	Liphistius erawan	14197	0.024	-0.361	NC_020323*
	Heptathelidae	Heptathela hangzhouensis	14215	-0.023	-0.235	NC_005924*
Xiphosura	Limulidae	Limulus polyphemus	14985	0.114	-0.399	NC_003057*

* refers to the mitogenomes that have been downloaded from GenBank.