Glossary

aethalium (pl. aethalia) a relatively large, stalkless, rounded fruiting body formed from all or most of the plasmodium, e.g. Fuligo septica.
amoeba (pl. amoebae) (Gk amoiba to change) any single-celled eukaryote that is naked and changes shape due to irregular extension and retraction of pseudopodia.
amylase any of a group of enzymes that are present in saliva, pancreatic juice, and parts of plants; they catalyze the hydrolysis of starch to sugar to produce carbohydrate derivatives.
aphanoplasmodium (pl. aphanoplasmodia) usually invisible type of plasmodium characteristic of members of the Stemonitales.
apomixis form of reproduction that occurs without the fusion of a male and female gamete resulting in all stages in the life cycle being diploid.
axenic applied to a culture that consists of only one species.

Aethalium of Fuligo septica
aphanoplasmodium
Columella - an extension of the stalk inside the sporotheca
Calyculi of Trichia decipiens

calyculus (pl. calyculi) persistent cup-like structure formed from the base of the peridium. It surrounds the base of the spore mass.
capillitium (pl. capillitia) sterile thread-like structures found within the spore mass of some slime moulds.
cellulase any of several enzymes produced chiefly by fungi, bacteria, and protozoans that break down cellulose.
columella an extension of the stalk inside the sporotheca.
cortex thick, usually hard covering of the spore mass of an aethalium.

Cortex of Reticularia splendens
Frass on Craterium minutum
Plasmodiocarp of Willkommlangea reticulata
Phaneroplasmodium

dehiscent bursting or splitting open at maturity to release spores.
diploid an organism with two complete chromosome sets.
duplex of two types.
eukaryote any organism whose cells have a nucleus and other structures enveloped by a double membrane. Some unicellular organisms are eukaryotes; all multicellular organisms—plants, animals and fungi—are eukaryotes.
evanescent ephemeral or transitory.
extant still living.
flagellum (pl. flagella) thread-like appendage which usually functions in locomotion and sometimes feeding.
frass material that results from the chewing actions of phytophagous (i.e. plant-eating) insects. It can be powdery, but more often it resembles tiny pellets of plant fragments.
fugacious withering or dropping off early.
fructification also called fruiting body.
gamete a specialised haploid cell (sometimes called a sex cell) whose nucleus and often cytoplasm fuses with that of another gamete (from the opposite sex or mating type) in the process of fertilisation, thus forming a diploid zygote. In some animals (e.g. mammals) the gametes are differentiated: the male is a motile sperm with reduced cytoplasm; the female is immobile with a large amount of cytoplasm called the egg or ovum which develops when stimulated. Usually there are many small male gametes and one or few female gamete.
haploid an organism with one complete set of chromosomes in the cell nucleus.
hyphomycete class of imperfect (i.e. asexual) fungi in which the vegetative stage is typically well-developed mycelium.
hypothallus thin membrane or limey layer deposited by the plasmodium at the time of fruiting.
lenticular lens shaped.
meiosis the process of cell division in sexually reproducing organisms that reduces the number of chromosomes in reproductive cells from diploid to haploid, leading to the production of gametes in animals and spores in plants.
micrometer (μm) 1/1000 of a millimetre or 10¯⁶ metres.
myxamoeba (pl. myxamoebae) microscopic uninucleate amoeboid trophic stage in the life cycle of a myxomycete; may also function as gamete.
myxocarp spore-producing structure, i.e. fruiting body, of myxomycete.
nivicolous species found at the edge of melting snow in regions that have at least 3 months of snow each year.
obligate applies to an organism that can survive only if a particular environmental condition is satisfied.
ostiole an opening through which spores are dispersed.
palladium a soft silver/white metal that resembles platinum.
peridium membrane that encases the spores; can be limey, persistent, iridescent or evanescent.
perithecium (pl. perithecia) a small flask-shaped fruiting body in ascomycetous fungi that contains the ascospores.
phaneroplasmodium (pl. phaneroplasmodia) type of plasmodium that is usually conspicuous, characteristic of members of the Physarales.
phenotypic plasticity the ability of an organism to change its phenotype (obseervable traits, behaviour etc) in response to changes in the environment.
plasmodiocarps fruiting bodies that resemble veins in the plasmodium.
plasmodium (pl. plasmodia) acellular, multinucleate mass of protoplasm that is the main feeding stage of the myxomycete.
protoplasmodium (pl. protoplasmodia) type of plasmodium that is microscopic and gives rise to usually one small fruiting body.
pseudoaethalium (pl. pseudoaethalia) resemble aethalia, but are actually composed of individual, closely-packed sporangia.
pseudocapillitium (pl. pseudocapillitia) irregular plates, tubes or thread-like elements within spore mass of aethalia; like capillitia but not formed in the same way.
pseudopodia (Gk pseudes false; podos foot) a protusion, usually temporary, that functions in locomotion and ingestion of food.

Pseudoaethalium of Tubifera sp.
Pseudocapillitium of Reticularia splendens
Sclerotium of Badhamia utricularis
Stalked sporangia of Physarum globuliferum

resupinate lying flat on a surface.
reticulate like a net.
SEM scanning electron microscope.
sessile without a stalk.
sporangium (pl. sporangia) type of fruiting body formed when a plasmodium breaks up into a number of small portions which develop into stalked or sessile units.
spore single cell reproductive body capable of growing into a new organism. Myxomycete spores are often spherical, around 8-14 um in diameter and can be ornamented with warts, spines or ridges.

Didymium melanospermum spores
Perichaena depressa spores
Cribraria violacea spores
Stemonitopsis hyperopta spores

sporophore term sometimes used for sporangium; some authors use this term only for myxos bearing external spores, e.g Ceratiomyxa fruticulosa.
sporotheca (pl. sporothecae) part of sporangium that contains the spores, sometimes called sporocyst or spore mass.
stipe stalk.
substratum (pl. substrata) the material on which something appears/grows. E.g. soil, rock, bark, leaves etc.
subulate narrowing to a point from a wide base.
swarm cells (or swarmers) microscopic uninucleate flagellated trophic stage in myxomycete life cycle; may also function as a gamete (see p. 8).
syngamy the union of nuclei of two gametes to produce a zygote nucleus following fertilisation.
trophic of or involving the feeding habits or food relationship of different organisms in a food chain.
type specimen original specimen used by an author to describe a new species, subspecies or variety (also known as holotype).
vacuole a membrane-bound sac.
zyzgote fertilised ovum, formed from fusion of male and female gametes.