Key to the species of Chnoospora
| 1 | Fronds erect from a discrete base, silky colorless hairs common along mid an upper parts of plants; growing high in the intertidal region, usually on vertical or sloping igneous rocks | C. minima |
| 1 | Fronds decumbent to prostrate, bases spreading; axes terete, without colorless hairs; usually growing on horizontal calcareous surfaces below low tide on reef flats | C. implexa |