Key to the kenyaensis species group

1 0–1 preopercular spines, dorsal-fin rays 95–102, anal-fin rays 80–85, total vertebrae 55–59, pseudobranchial filaments 2–4, orbit length 4.3–6.1% SL and 22–31% HL................................................................. 2

- 2 preopercular spines, dorsal-fin rays 91, anal-fin rays 75, total vertebrae 52, pseudobranchial filaments 6, orbit length 4.1% SL and 18% HL.......................................................................... N. japonicus n. sp.

2 0 preopercular spines, central ocellus distance 53–57% SL, precaudal vertebrae 13, developed gill rakers 8–10, pelvic-fin length 10–12% SL.......................................................................... N. kenyaensis

- 1 preopercular spine, central ocellus distance 45–50% SL, precaudal vertebrae 12, developed gill rakers 14–16, pelvic-fin length 16–22% SL........................................................................... N. ocellatus