Gut symbionts in Arthropods


Trichomycetes are a cosmopolitan group of fungi and protists that grow obligately in the guts of insects, crustaceans, and millipedes that live in freshwater, marine, or terrestrial habitats. The taxonomy of these organisms is based primarily on the morphology of the vegetative thallus; spore type, dimensions and nature of spore production; host type and location in the gut; and habitat.

Dr. R.W. Lichtwardt, University of Kansas constructed the original keys for these microorganisms in 2004 and has updated them as new taxa were added so they include all currently known valid species. The Lucid key software has been updated and the keys have been moved to the Lucid Key Server and will continue to be updated to reflect the taxa assigned to the group.

Start Trichomycete Keys


The keys here can be referenced as Lichtwardt, R.W. 2004. Keys to the Trichomycetes: URL We typically add a note with the reference that data in the keys have been updated regularly since 2004.

Also worth noting is that the references that are cited in each species description in the keys can be found in the References section of the monograph which can be accessed through the link at the bottom of this page.


Oct. 2022

New species Harpella filispora, Legerioides culicicola, Smittium basiangustatum, S. nodiradicatum, and Orphella columbiensis from Canada added.

Also added these to the Mongraph, along with some recent references.

The revised monograph by Lichtwardt, White and Cafaro published online in 2001(revised in 2016) has now had the taxonomic chapter (Chapter 11) as well as the references section updated (Nov. 2021). Lucid Central has agreed to host this important document along with the Keys. The monograph can be accessed on this site by clicking on the link below.

THE TRICHOMYCETES: Fungal Associates of Arthropods. 



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