Table 2.

Comparison of genetic markers with evaluation criteria and their suitability for molecular systematics of nematodes

Criteria	Nuclear gene/region				Mitochondrial gene
	ITS1	ITS2	18S	28S	cox1	12S	16S
Nucleotide saturationa	Yes	Yes	No	No	No	No	No
Clade arrangement (monophyly)b	na	na	4/4	2/4	3/4	3/4	3/4
Presence of indels	High				Low
Availability of full-length sequences	Partial sequences				Full-length sequences

^aNumber of differences between two sequences becomes a less accurate indicator of the actual number of nucleotide substitutions. “Yes” indicates that most of the sites have already been changed before (Iss > Iss.c), indicating nucleotide saturation

^bNumber of clades (n) that are monophyletic out of the total number of expected monophyletic clades (e.g. n/4)

Abbreviations: na, not applicable