1	Blades of some compound chaetae with one or more long basal spines	2
–	Blades of all compound chaetae with short, uniform spines on margin	4
2	Longer blades of each parapodium with 2–3 long basal spines	Syllides japonica Imajima, 1966 (1)
–	Blades of some compound chaetae with single, long basal spine	3
3	Blades of medium length compound chaetae with a long basal spine. Tips of dorsal simple chaetae blunt	Syllides bansei Perkins, 1981 (1)
–	Blades of longest and second pairs of compound chaetae with a long basal spine. Tips of dorsal simple chaetae enlarged and rounded, with some minute spines dorsally	Syllides benedicti Banse, 1971 (1)
4	Shafts of compound chaetae distally with 1–2 spines distinctly long and thick. Tips of dorsal simple chaetae enlarged and rounded	Syllides convoluta Webstery Benedict, 1884 (1)
–	Distal part of shafts with few, thin spines or smooth. Dorsal simple chaetae ending in a blunt tip	Syllides fulva (Marion & Bobretzky, 1875) (1)