| Alexandrium Halim, 1960 |
| Alexandrium acatenella (Whedon & Kof.) Balech, 1985 |
| Alexandrium affine (H. Inoue & Fukuyo) Balech, 1985 |
| Alexandrium angustitabulatum F.J.R. Taylor, 1995 |
| Alexandrium catenella (Whedon & Kof.) Balech, 1985 |
| Alexandrium cohorticula (Balech) Balech, 1985 |
| Alexandrium compressum (Fukuyo, K. Yoshida & H. Inoue) Balech, 1995 |
| Alexandrium concavum (Gaarder) Balech, 1985 |
| Alexandrium fraterculum (Balech) Balech, 1985 |
| Alexandrium gaarderae Nguyen-Ngoc & J. Larsen, 2004 |
| Alexandrium kutnerae (Balech) Balech, 1985 |
| Alexandrium leei Balech, 1985 |
| Alexandrium margalefi Balech, 1994 |
| Alexandrium minutum Halim, 1960 |
| Alexandrium monilatum (Howell) Balech, 1995 |
| Alexandrium ostenfeldii (Paulsen) Balech & Tangen, 1985 |
| Alexandrium peruvianum (Balech & R.B. Mendiola) Balech & Tangen, 1985 |
| Alexandrium pseudogonyaulax (Biecheler) Horiguchi ex Yuki-Fukuyo, 1992 |
| Alexandrium tamarense (Lebour) Balech, 1995 |
| Alexandrium tamiyavanichii Balech, 1994 |