Laboulbeniomycetes
Encyclopedia
The Laboulbeniomycetes are a unique group of fungi
that are apparent external parasites of insect
s and other arthropod
s, both terrestrial and aquatic. These fungi are minute; their fruiting bodies commonly measure less than one millimeter. They live on the antennae, the mouthparts or other body regions of their arthropod hosts. Although several species of Laboulbeniomycetes have more or less extensive, root-like hyphal systems (haustoria
) inside their hosts, as a group these fungi are apparently harmless to the animals they live on. These fungi are usually apparent only on adult hosts; apparently immature arthropods eliminate them during ecdysis
(adult arthropods no longer molt). Some fungi in the Laboulbeniomycetes have separate female and male individuals, like Herpomyces.
In the micrograph to the right, two flask-shaped, about 0.3 mm long female fruting bodies of Herpomyces periplanetae can be seen. They are full of ascospore
s. Between them, there are two short, finger-like male individuals. Below, a part of a striated foot cell is visible. In nature, the fruiting bodies sit on the foot cell, which lies on the insect's antennae. Herpomyces periplanetae is a very widespread parasite on the antennae of adult cockroach
es in the genus Periplaneta, like the common American cockroach
, Periplaneta americana.
Fungus
A fungus is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds , as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which is separate from plants, animals, and bacteria...
that are apparent external parasites of insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s and other arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s, both terrestrial and aquatic. These fungi are minute; their fruiting bodies commonly measure less than one millimeter. They live on the antennae, the mouthparts or other body regions of their arthropod hosts. Although several species of Laboulbeniomycetes have more or less extensive, root-like hyphal systems (haustoria
Haustorium
In botany, a haustorium is the appendage or portion of a parasitic fungus or of the root of a parasitic plant that penetrates the host's tissue and draws nutrients from it. Haustoria do not penetrate the host's cell membranes.Fungi in all major divisions form haustoria...
) inside their hosts, as a group these fungi are apparently harmless to the animals they live on. These fungi are usually apparent only on adult hosts; apparently immature arthropods eliminate them during ecdysis
Ecdysis
Ecdysis is the moulting of the cuticula in many invertebrates. This process of moulting is the defining feature of the clade Ecdysozoa, comprising the arthropods, nematodes, velvet worms, horsehair worms, rotifers, tardigrades and Cephalorhyncha...
(adult arthropods no longer molt). Some fungi in the Laboulbeniomycetes have separate female and male individuals, like Herpomyces.
In the micrograph to the right, two flask-shaped, about 0.3 mm long female fruting bodies of Herpomyces periplanetae can be seen. They are full of ascospore
Ascospore
An ascospore is a spore contained in an ascus or that was produced inside an ascus. This kind of spore is specific to fungi classified as ascomycetes ....
s. Between them, there are two short, finger-like male individuals. Below, a part of a striated foot cell is visible. In nature, the fruiting bodies sit on the foot cell, which lies on the insect's antennae. Herpomyces periplanetae is a very widespread parasite on the antennae of adult cockroach
Cockroach
Cockroaches are insects of the order Blattaria or Blattodea, of which about 30 species out of 4,500 total are associated with human habitations...
es in the genus Periplaneta, like the common American cockroach
American cockroach
The American cockroach , also known as the waterbug, or misidentified as the palmetto bug , is the largest species of common cockroach, and often considered a pest. None of the Periplaneta species are endemic to the Americas; despite the name, P...
, Periplaneta americana.