The Harpellales are an order

Order (biology)

In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...

 of fungi classified in the subdivision Kickxellomycotina

Kickxellomycotina

Kickxellomycotina is a fungus grouping.The name was changed from "Harpellomycotina", because "Kickxellomycotina" had an older stem.Orders include Asellariales, Kickxellales, Dimargaritales, and Harpellales.-External links:...

. Thalli are either unbranched or branched, producing basipetal series of trichospores. Zygospore

Zygospore

A zygospore is a diploid reproductive stage in the life cycle of many fungi and protists. Zygospores are created by the nuclear fusion of haploid cells. In fungi, zygospores are termed chlamydospores and are formed after the fusion of hyphae of different mating types...

s are biconical. Species in the order are found attached to the gut lining of aquatic larvae of Insecta or (rarely) Isopoda

Isopoda

Isopods are an order of peracarid crustaceans, including familiar animals such as woodlice and pill bugs. The name Isopoda derives from the Greek roots and...

. Harpellales are divided into two families, the Harpellaceae

Harpellaceae

The Harpellaceae are a family of fungi in the Harpellales order. The family contains 5 genera and 40 species....

 and the Legeriomycetaceae

Legeriomycetaceae

The Legeriomycetaceae are a family of fungi in the Harpellales order. The family contains 31 genera and 158 species.-Genera:*Allantomyces*Austrosmittium*Baetimyces*Barbatospora*Bojamyces*Capniomyces*Caudomyces...

. According to the Dictionary of the Fungi (10th edition, 2008), the order contains 38 genera

Genera

Genera is a commercial operating system and development environment for Lisp machines developed by Symbolics. It is essentially a fork of an earlier operating system originating on the MIT AI Lab's Lisp machines which Symbolics had used in common with LMI and Texas Instruments...

 and 200 species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

. The order was formally described in 1978 Mycotaxon

Mycotaxon

Mycotaxon is a peer-reviewed scientific journal that publishes papers on the nomenclature and taxonomy of the fungi, including lichens....

publication.

Species include Allantomyces zopilotei, Bojamyces olmecensis, Gauthieromyces viviparus and Graminella ophiuroidea.