Arcyria sp. (genus) (A slime mould)

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The genus Arcyria dates back to Linnaeus in 1753 through the species A. denudata.

Arcyria sporangia are brightly colored red, yellow, grey or white, mostly stalked, often in large groups easily seen with the naked eye. More than 50 species are known, many are common, and distributed worldwide. Collectors often encounter these colorful species on decaying logs as clusters of many sporangia often covering extensive areas.

Sporocarps are stalked sporangia, globose to ovoid to cylindrical, sometimes recumbent when long.

Peridium is thin and disappears quickly, sometimes leaving behind small fragments attached to the capillitium, and leaves a well marked cup called a calyculus which is often decorated with warts, spines or a reticulum.

Stalk is often packed with spore like bodies, large globose cells which always have a smooth wall.

Capillitium is an elastic network of branching and anastomosing threads which expand on maturity to assist in expelling the spores. These threads are ornamentated with spines, warts, cogs, rings and ridges with the ridges often arranged in a reticulate pattern. The capillitium is either firmly attached to the cup or so loose that it breaks away as a single unit in the slightest breeze.

Spore colour is much the same as the sporangium and they are covered in pale warts or spines – observed with oil immersion lens.

Arcyria sp. (genus) is listed in the following regions:

Canberra & Southern Tablelands | South Coast