''Rhopalomyces elegans'' is a common species of zygomycete fungus, and the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

of the genus ''

Rhopalomyces ''Rhopalomyces'' is a genus of fungi in the family Helicocephalidaceae. The type species, '' Rhopalomyces elegans'', is a predator of nematode eggs. '' Verticillium psalliotae'' is a parasite Parasitism is a close relationship between ...

''. Widely distributed, it is found in soil, rotting plant material, and animal dung. It is a facultative parasite of

nematode The nematodes ( or grc-gre, Νηματώδη; la, Nematoda) or roundworms constitute the phylum Nematoda (also called Nemathelminthes), with plant-Parasitism, parasitic nematodes also known as eelworms. They are a diverse animal phylum inhab ...

eggs.

Taxonomy

The species was first recorded by

August Carl Joseph Corda August Carl Joseph Corda (1809–1849) was a Czech physician and mycologist. This botanist is denoted by the author abbreviation when citing a botanical name. Early life and education Corda was born in Reichenberg (now Liberec), Bohemia on No ...

, who isolated it from material collected from a

Prague Prague ( ; cs, Praha ; german: Prag, ; la, Praga) is the capital and largest city in the Czech Republic, and the historical capital of Bohemia. On the Vltava river, Prague is home to about 1.3 million people. The city has a temperate ...

greenhouse. In 1962, Ellis and Hesseltine demonstrated a method to grow the species in pure culture by using a

growth medium A growth medium or culture medium is a solid, liquid, or semi-solid designed to support the growth of a population of microorganisms or cells via the process of cell proliferation or small plants like the moss ''Physcomitrella patens''. Differen ...

containing calf's liver and lamb fat. A year later, Ellis recognized four varieties of ''Rhopalomyces elegans'', defined by their growth in different media: ''minor'', ''crassus'', ''apiculatus'', and the nominate variety ''elegans''.

Description

When grown in pure culture conditions on a

petri dish A Petri dish (alternatively known as a Petri plate or cell-culture dish) is a shallow transparent lidded dish that biologists use to hold growth medium in which cells can be cultured,R. C. Dubey (2014): ''A Textbook Of Biotechnology For Class- ...

at a temperature of , ''Rhopalomyces elegans'' produces

hyaline A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none. Histopathology Hyaline cartilage is ...

(translucent), partially submerged

colonies In modern parlance, a colony is a territory subject to a form of foreign rule. Though dominated by the foreign colonizers, colonies remain separate from the administration of the original country of the colonizers, the '' metropolitan state'' ...

that fill the plate in about six days. The fungus produces large, dark brown conidiospores borne on a swollen vesicle at the end of a conidiophore. The vesicles measure 40–63

μm The micrometre ( international spelling as used by the International Bureau of Weights and Measures; SI symbol: μm) or micrometer (American spelling), also commonly known as a micron, is a unit of length in the International System of Unit ...

in diameter. The

hypha 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 or ...

e are very thin, measuring only 2 μm in diameter. '' Rhopalomyces magnus'' is similar in

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

, but only attacks eggs of

rotifer The rotifers (, from the Latin , "wheel", and , "bearing"), commonly called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic pseudocoelomate animals. They were first described by Rev. John H ...

Ecology

A common species, ''R. elegans'' is found in rotting plant material and animal debris, as well as dung associated with soil. The fungus is a

parasite Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has ...

eggs. When it encounters an egg, it produces hyphae that form a structure on the egg surface similar to an

appressorium An appressorium is a specialized cell typical of many fungal plant pathogens that is used to infect host plants. It is a flattened, hyphal "pressing" organ, from which a minute infection peg grows and enters the host, using turgor pressure capable ...

. This structure produces a narrow infection tube that penetrates the egg shell. Once inside, fungal hyphae proliferate by branching and expanding, eventually filling the interior of the egg and absorbing the nutrients within.'' R. elegans'' may be able to attack the larval and adult stages of some nematode species. ''Rhopalomyces elegans'' can itself be parasitized by the fungi '' Mycogone perniciosa'' and '' Verticillium psalliotae''. ''Verticillium psalliotae'' is a saprobic soil-dwelling fungus that is a parasite of the common commercially grown button mushroom (''Agaricus bisporus''). ''R. elegans'' may serve as a

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contro ...

for the pathogen, and may harbor the parasite in its thick cell walls.

References

External links

{{Taxonbar, from=Q7321429 Fungi described in 1839 Carnivorous fungi Zygomycota Taxa named by August Carl Joseph Corda