| Ectocarpus rallsiae Vickers, 1905 |
| Ectocarpus rhodochortonoides Børgesen, 1914 |
| Ectocarpus sandrianus Zanardini, 1843 |
| Ectocarpus saundersii Setch. & N.L. Gardner, 1922 |
| Ectocarpus siliculosus (Dillwyn) Lyngb., 1819 |
| Ectocarpus siliculosus f. subulatus (Kütz.) Setch. & N.L. Gardner, 1922 |
| Ectocarpus siliculosus var. dasycarpus (Kuck.) Gallardo, 1992 |
| Ectocarpus siliculosus var. parvus D.A. Saunders, 1898 |
| Ectocarpus siliculosus var. pygmaeus (Aresch.) Gallardo, 1992 |
| Ectocarpus siliculosus var. siliculosus (Dillwyn) Lyngb., 1819 |
| Ectocarpus siliculosus var. subulatus (Kütz.) Gallardo, 1992 |
| Ectocarpus simplex P. Crouan & H. Crouan, 1867 |
| Ectocarpus simulans Setch. & N.L. Gardner, 1922 |
| Ectocarpus sonorensis E.Y. Dawson, 1944 |
| Ectocarpus spinulosus Mont., 1840 |
| Ectocarpus subcorymbosus Farlow & Holden, 1905 |
| Ectocarpus subulatus Kütz., 1843 |
| Ectocarpus taoniae Setchell & N.L. Gardner, 1922 |
| Ectocarpus tomentosus (Huds.) Lyngb., 1819 |
| Ectocarpus variabilis (D.A. Saunders) G.M. Sm., 1942 |