Lagenidium giganteum

The life cycle and habitat of L. giganteum f. caninum is similar to its related species, L. giganteum, which can grow without a host. It can be found in bodies of fresh water and is observed to sustain mosquito populations. The life cycle of L. giganteum is initiated by a biflagellate zoospore that infects a mosquito larvae host by attachment, and undergoes encystment, penetration, and growth. The zoospore production can occur either by sexual or asexual reproduction that seems to require exogenous sources of sterols structurally related to cholesterol. For mycelial growth, the organism kills the host by starvation. Cells can reproduce asexually while forming an exit tube, where the content migrates to the tube's tip and quickly matures into zoospores, or alternately, two cells can fuse, forming oospores as seen in Saprolegnia sp. cycle. Lagenidum giganteum can undergo a latent stage surviving for long periods (months to years). The saprophytic or vegetative stage of the oomycetes from the genus Lagenidium is characterized by filamentous mycelial growth and requires little carbon and nitrogen sources. Hyphae can survive indefinitely as a saprophyte while using energy source from rotting vegetation, dead insects, or other organic material.