Key to species of Paradalhousia n. gen.

1 Nuchal lobes parallel; middle chaetigers with notacicular and neuracicular lobes tapered, blunt or pointed............... 2

- Nuchal lobes divergent; middle chaetigers with notacicular and neuracicular lobes tapered, blunt; 20–40 neurochaetae per bundle, blades 5–22 times longer than wide, distal tooth falcate; middorsal peristomial tubercle pale................................................................ P. anomala (Chamberlin, 1919) n. comb., reinstated; Marshall Islands

2(1) Neurochaetae about 20 per bundle, blades 5–11 times longer than wide ( fide Pettibone 1970, Fig. 19e); distal tooth straight; middle chaetigers with notacicular and neuracicular lobes tapered, pointed; middorsal peristomial tubercle brownish............................................................ P. papillosa (Monro, 1926) n. comb., reinstated, China Sea

- Neurochaetae about 50 per bundle, blades 5–15 times longer than wide ( fide Pettibone 1970, Fig. 17e); distal tooth falcate; middle chaetigers with notacicular and neuracicular lobes tapered, blunt; middorsal peristomial tubercle pale.................................................................. P. oculata (Treadwell, 1906), n. comb., reinstated, Hawaii