Entophlyctis helioformis JEL805 v1.0
Entophlyctis helioformis JEL 805. Stages in development, left to right: motile zoospore, encysted zoospore forms a germ tube which develops a prosporangium at the apex, developing sporangium, mature sporangium with long discharge tube. Photos by Joyce Longcore
Entophlyctis helioformis JEL 805. Stages in development, left to right: motile zoospore, encysted zoospore forms a germ tube which develops a prosporangium at the apex, developing sporangium, mature sporangium with long discharge tube. Photos by Joyce Longcore

Entophlyctis helioformis (JEL 805) is a chytrid isolated from moribund green algae (Nitella) collected in Pushaw Lake, Penobscot County, Maine in 2013 by J. E. Longcore. The species was originally described by Dangeard (1888) from multiple genera of Characeae. The parasitic or saprotrophic nature of the species on Characeae remains unclear (Karling 1928). Phylogenetically, E. helioformis has been allied with the amphibian killing chytrid Batrachochytrium dendrobatidis and Homolaphlyctis polyrhiza in the Rhizophydiales (Longcore et al. 2011). Entophlyctis is a polyphyletic genus (James et al. 2000) and is characterized by exogenous, monocentric development in which a zoospore stops swimming, encysts, and develops a germ tube through which the spore nucleus passes and forms a prosporangium at the tip. This type of development is similar to that observed in B. dendrobatidis in vivo (Greenspan et al. 2012). The complete genome sequence of E. helioformis will be useful for comparative genomics to understand the life cycle and nutritional mode of the fungus from an enzymatic perspective and to provide greater insight into the evolutionary transition from algal host to amphibian.

References:
Dangeard, P. A. (1888).  Les Peridiniens et leurs parasites. Jour. Bot. 2: 141-146.
Greenspan, S. E., J. E. Longcore, and A. J. K. Calhoun. (2012). Host invasion by Batrachochytrium dendrobatidis: fungal and epidermal ultrastructure in model anurans. Diseases of Aquatic Organisms. 100: 201-210.
James, T. Y., D. Porter, C. A. Leander, R. Vilgalys, and J. E. Longcore. (2000). Molecular phylogenetics of the Chytridiomycota supports the utility of ultrastructural data in chytrid systematics. Canadian Journal of Botany 78: 336-350.
Karling, J. S. (1928). Studies in the Chytridiales I. The life history and occurrence of Entophlyctis heliomorpha (Dang.) Fischer. American Journal of Botany 15: 32-42.
Longcore, J. E., P. M. Letcher, and T. Y. James. (2011). Homolaphlyctis polyrhiza gen. et sp. nov., a species in the Rhizophydiales (Chytridiomycetes) with multiple rhizoidal axes. MycoTaxon 118: 433-440.