Maullinia

Maullinia
E: Resting spores of Maullinia sp. resting spores in Durvillaea antarctica
Scientific classification
Domain:	Eukaryota
Clade:	Diaphoretickes
Clade:	SAR
Phylum:	Endomyxa
Class:	Phytomyxea
Order:	Phagomyxida
Family:	Phagomyxidae
Genus:	Maullinia I. Maier, E. R. Parodi, R. Wester-meier et D. G. Müller 2000

Maullinia is a genus of intracellular, phytomyxid parasites found across the Southern Hemisphere though primarily in Chile, The Prince Edward Islands, South Africa, Australia, and New Zealand.^{[1][2][3][4][5]} These parasites infiltrate the cells of their brown algal hosts via cytoplasmic extensions called plasmodia that divide synchronously,^[1] becoming increasingly multi-nucleate and engulfing the host cell organelles as they grow.^[1][3] Eventually, as the plasmodia fill the entire cell volume, the host cells become hypertrophied and grow to 3- 4x their original size,^[2] showing up as swollen appendages or galls on the host tissue at a macroscopic level.^[1][3] These swollen regions will burst alongside the mature Maullinia plasmodia, releasing biflagellated zoospores to the inter- and extracellular space to disperse the infection further.^[6] Zoospores can come from sporangial plasmodia,^[1] as in M. ectocarpii, or from resting spores, as in M. braseltonii.^[3]

As Maullinia can infect a wide range commercially important brown algal hosts, they present a significant threat to kelp farming and mariculture efforts.^[1] These infections could also cause significant harm on a global scale to natural populations, as they are able to disperse over long distances via rafting and tend to thrive in the cooler waters where kelp are often found.^[4][5]