Aphanomyces is a genus of water moulds. As of 2003 there were about 45 described species. Many of these water moulds are known as ecologically important pathogens of species of plants and animals, including fish, crustaceans, and agricultural crop plants. Aphanomyces water moulds are "one of the most important yield-limiting factors in production of legumes and sugarbeet." epizootic ulcerative syndrome, mycotic granulomatosis
- Aphanomyces iridis
- Aphanomyces irregularis
- Aphanomyces keratinophilus
- Aphanomyces laevis – cotton-wool disease of fish
- Aphanomyces magnusii
- Aphanomyces norvegicus
- Aphanomyces ovidestruens
- Aphanomyces parasiticus
- Aphanomyces patersonii
- Aphanomyces phycophilus
- Aphanomyces pisci
- Aphanomyces piscicida
- Aphanomyces polysporis
- Aphanomyces raphani – black root disease of radish
- Aphanomyces salsuginosus
- Aphanomyces scaber
- Aphanomyces sparrowii
- Aphanomyces stellatus
- Aphanomyces volgensis