The Laboulbeniales is an order of

fungi A fungus (: fungi , , , or ; or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and mold (fungus), molds, as well as the more familiar mushrooms. These organisms are classified as one ...

within the

class Class, Classes, or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used d ...

Laboulbeniomycetes. They are also known by the colloquial name beetle hangers or labouls. The order includes around 2,325 species of

obligate {{wiktionary, obligate As an adjective, obligate means "by necessity" (antonym '' facultative'') and is used mainly in biology in phrases such as: * Obligate aerobe, an organism that cannot survive without oxygen * Obligate anaerobe, an organism ...

insect ectoparasites that produce cellular thalli from two-celled

ascospore In fungi, an ascospore is the sexual spore formed inside an ascus—the sac-like cell that defines the division Ascomycota, the largest and most diverse Division (botany), division of fungi. After two parental cell nucleus, nuclei fuse, the ascu ...

s. Of the described Laboulbeniales, Weir and Hammond 1997 find 80% to be from

Coleoptera Beetles are insects that form the Taxonomic rank, order Coleoptera (), in the superorder Holometabola. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 40 ...

and the next largest group to be the 10% from

Diptera Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advance ...

. Recently, the genus '' Herpomyces'', traditionally considered a basal member of Laboulbeniales, was transferred to the order Herpomycetales based on

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

data. Laboulbeniales typically do not kill their hosts, although they may impair host fitness if the parasite density is high. Laboulbeniales form individual thalli, and lack vegetative

hyphae A hypha (; ) is a long, branching, filamentous structure of a fungus, oomycete, or actinobacterium. In most fungi, hyphae are the main mode of vegetative growth, and are collectively called a mycelium. Structure A hypha consists of one o ...

. A thallus is attached to its host by a simple dark-colored foot cell, or a rhizoidal haustorium through which the fungus penetrates the exoskeleton of its host to draw nutrients from the hemolymph. The external part of the thallus may form male structures (antheridia) or female structures (trichogynes and perithecia), or both. New infections are initiated when spores from the perithecia attach to a compatible insect host. Spore transmission can sometimes occur during insect copulation, which may account for the different site specificity sometimes observed in male and female hosts. These fungi do not grow apart from their hosts. Foundational work on the Laboulbeniales was completed by the American mycologist Roland Thaxter (1858–1932), particularly in his five-volume, illustrated ''Monograph of the Laboulbeniaceae'' (Thaxter 1896, 1908, 1924, 1926, 1931). Recent

work has shown that some taxa are complexes of multiple species segregated by host, for example ''Hesperomyces virescens''. The classification of the order Laboulbeniales follows Isabelle Tavares (1985) but several taxa in that system are

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

References

External links

*
Bugguide.net. ''Harmonia axyridis'' with Laboulbeniales fungusArticle about Laboulbeniales on Diptera by Jan MácaLaboulbeniales homepage by Dr. Alex Weir
Ascomycota orders {{Ascomycota-stub

References

Further reading

External links