ichthyophonus ichthyophonus ichthyophonus is a genus of unicellular eukaryotic parasites of fish. they were once considered to be fungi, but phylogenetic evidence suggests they are protists related to both fungi and animals. ichthyophonus hyphae (or germ tubes) and schizonts of ichthyophonus hoferi scientific classification (unranked): opisthokonta (unranked): holozoa class: ichthyosporea order: ichthyophonida genus: ichthyophonusplehn & mulsow 1911 type species ichthyophonus hoferiplehn & mulsow 1911 species ichthyophonus gasterophilus ichthyophonus hoferi ichthyophonus intestinalis ichthyophonus irregularis ichthyophonus lotae species ichthyophonus gasterophilus (caullery & mesnil 1905) sprague 1965 ichthyophonus hoferi plehn & mulsow 1911 ichthyophonus intestinalis léger & hesse 1923 ichthyophonus irregularis rand et al. 2000 ichthyophonus lotae leger 1925