Antheridia - male gametangium found in Oomycota and members of the order Monoblepharidales (Chytridiomycota).

Antherozoid - motile male gamete of the order Monoblepharidales (Chytridiomycota).

Basal body - the base of a flagellum consisting of a cylinder of nine triplet microtubules. This structure arises from the centriole and is also called a kinetosome.

Bothrosome - a cell surface organelle which produces the ectoplasmic network and through which there is continuity from the network matrix to the cell cytoplasm. Also referred to as a Sagenogen. Only found in the Labyrinthulomycetes.

Chytrid - a general term used to describe members of the Chytridiomycota; previously restricted to members of the Chytridiales.

Coenocytic - nonseptate; referring to the fact that nuclei are present in the chytoplasm without being separated by cross-walls, that is, the nuclei lie in a common matrix. The hyphae of members of the Oomycota and Chytridiomycota are considered coenocytic.

Dimorphic - producing two morphologically distinct types of zoospores.

Diplanetic - refers to a dimorphic species in which two swarming periods occur (Oomycota). See also monoplanetic and polyplanetic.

Ectoplasmic net - a network of branching and anastomosing wall-less filaments which absorb nutrients and attach vegetative cells to the substrate.

Endobiotic - reproductive structure is inside of the substrate or host cell.

Endogenous - a form of thallus development in which the nucleus remains in an encysted zoospore that simply enlarges to form one or more sporangia.

Epibiotic - reproductive structure is on the outside of the substrate or host cell.

Flagellum - a hairlike structure with internal microtubules surrounded by a continuation of the plasma membrane that serves to propel a motile cell such as a zoospore.

Gametangium - a structure that contains gametes.

Gamete - a differentiated sex cell or a sex nucleus that fuses with another in sexual reproduction.

Heterokont - a biflagellate condition in which the two flagella are unequal in length, movement, or form; especially a cell with one trailing whiplash flagellum and one anteriorly directed flagellum bearing flagellar hairs (tinsel flagellum).

Holocarpic - refers to an organism with a thallus that is converted entirely into one or more reproductive structures.

Inoperculate - used in reference to a sporangium that lacks an operculum (hinged cap).

Kinetosome - See Basal body.

Meiospore - a spore formed after meiosis.

Meiosporangium - a sporangium in which meiosis occurs; used in reference to certain Chytridiomycota.

Microbody-Lipid Globule Complex - an association of lipid bodies, microbodies, mitochondria and membrane cisternae observed at the transmission electron microscopic level in zoospores of aerobic Chytridiomycota.

Mitospore - a spore with a nucleus that has been formed by mitosis; an asexual spore.

Mitosporangium - sporangium in which mitosis occurs; used in reference to certain Chytridiomycota.

Monomorphic - producing zoospores of a single morphological type.

Monoplanetic - refers to zoospores that have only one swarming period.