Definition

Noun: - A taxonomic subclass within the class Basidiomycetes. This category is used in some classification systems to group together certain basidiomycetous fungi, most notably the rusts and smuts, which are often plant pathogens. These fungi are characterized by having a heterobasidium, a type of basidium (spore-producing structure) that is often septate (divided by cross-walls) or deeply divided.

Usage

• This term is used primarily in specialized mycological (fungal) taxonomy. It refers to a formal scientific grouping of fungi.
• Example: "In some older classification schemes, the rust fungi were placed in the ."
• Example: "The includes important agricultural pathogens like wheat rust."

Advanced Usage

• The classification of fungi is subject to change with new genetic research. The term "Heterobasidiomycetes" is more historical and is often replaced in modern phylogenetic systems by groups like "Pucciniomycotina" (rusts) and "Ustilaginomycotina" (smuts). Therefore, you might encounter it in older scientific literature.
• Example: "The concept of has largely been superseded by molecular phylogenetic classifications."

Variants and Related Words

• Heterobasidiomycete (noun, singular): A member of the subclass Heterobasidiomycetes.
  • Example: "A typical heterobasidiomycete produces teliospores."
• Heterobasidium (noun): The characteristic septate or divided basidium from which the group derives its name.
• Homobasidiomycetes (noun): The contrasting subclass containing fungi with simple, non-septate basidia, such as typical mushrooms.

Synonyms

• Heterobasidiomycetidae: An alternative taxonomic rank (subclass) name with the same meaning.
• Phragmobasidiomycetes: An older, roughly equivalent term emphasizing the septate (phragmate) nature of the basidium.

Related Terms (Not Synonyms)

• Rust fungi / Uredinales: A major order of plant-pathogenic fungi within this group.
• Smut fungi / Ustilaginales: Another major order of plant-pathogenic fungi within this group.
• Basidiomycota: The phylum to which all these fungi belong.
• Basidiomycetes: The class from which the subclass is derived.

Noun

1. category used in some classification systems for various basidiomycetous fungi including rusts and smuts