Neither slimy nor mouldy


Lamproderma echinulatum 0968
10 August 2017 Part of a large fruiting of Lamproderma echinulatum

At least once a year slime moulds make the news. On December 21 2016 the headline in Science Daily was ‘Giant cell blob can learn and teach’. The article explained how the plasmodial stage of a slime mould—essentially a moving feeding giant brainless cell—can transmit what it has learned to a fellow slime mould when the two combine.

Acellular or plasmodial slime moulds, also known as myxomycetes or myxogastrids, are ubiquitous opportunistic organisms. They are most abundant in temperate forests but they also occur in tropical forests, alpine areas, heathlands, grasslands, deserts, and arctic and sub‑Antarctic regions. In short, wherever there is organic material.

Myxomycetes were once included with plants when all living things were placed in just two kingdoms – plants and animals. When more kingdoms were created to encompass a vastly more complex world than was originally imagined, slime moulds were moved to the kingdom fungi. Indeed, they are often described as fungus‑like organisms and, like most fungi, they make only a relatively brief appearance at their fruiting body stage. However, they do not have any structures analogous to fungal hyphae, so when their pulsating feeding plasmodial stage was discovered they were moved to the animal kingdom. Then their single‑celled amoeboid feeding stage was observed and they were moved again, this time to the kingdom protozoa. However, this kingdom does not encompass organisms that have an amoeboid, plasmodial AND spore-bearing stage. They are now considered to be Amoebozoans but whether Amoebozoa is a supergroup or a kingdom is matter of some debate.

My research is about another stage in the lives of these intriguing organisms. The reproductive or spore-bearing stage comprises fruiting bodies that range in size from large amorphous blobs to tiny delicate structures little more than 2 mm high. (Background to the study and descriptions of the study site can be found on the Slime Mould Log.)