When we think of living things, most people tend to think immediately of animals and plants. This is logical since they are two of the types of living things we can directly think of most often. But the truth is that the animal and plant kingdoms are not the only ones that exist: there are also the monkey kingdom (to which bacteria belong), the protista or protoctist kingdom (in which we find various protozoa), and the fungi kingdom.

As far as this last kingdom is concerned, the first image that usually comes to mind is that of a mushroom, but the truth is that there are a large number of types of mushrooms (not in vain, we are dealing with one of the five great groups of living beings). In this article we’ll look at some of the best known.

What is a mushroom?

We call mushroom to the exponent of one of the five existing kingdoms of living beings , which is characterized by being constituted by eukaryotic cells (that is to say that they possess a nucleus in which the DNA is found) with a cell wall composed mainly of chitin and by its way of feeding, by means of absorption but heterotrophic.

This last term, heterotrophic, indicates that fungi, like animals, depend on the transformation of external organic matter into energy to survive. In other words, they need to consume matter that comes from or belongs to other living beings.

In fact, in this sense, fungi are very important at an ecological level since these beings are considered to be one of the main decomposers of dead matter, their fundamental contribution to the maintenance of the ecosystem.

The mushroom kingdom is certainly vast, with a huge variety of species and varieties. That is why there is a great variety of possible classifications into which these life forms can be divided , of which we will see several.

1. Types of mushrooms according to their basic forms

One of the fastest and easiest classifications to make is linked to the fact that as a rule we can find three main ways. It is a very simple classification that leaves aside the enormous diversity that we can find, but it is effective. In this sense we can find three main types.

1.1. Mushrooms

This is the most prototypical type of fungus for most people. In fact the term does not refer so much to the whole being but to one of its parts: the outermost part, corresponding to its fruiting and which is usually shaped like an umbrella or hat .

The rest of the fungus would be found underground (or below the surface where it is growing). Thus, technically we could differentiate between mushroom and fungus in the sense that the mushroom is only a part of a certain type of fungus. It is important to bear in mind that not all of them are edible , and many species can be poisonous and even deadly for us.

1.2. Yeast

The fungi classified within the group of yeasts are characterized by the way they decompose matter, this mechanism being fermentation (although not only fungi can use it).

Carbohydrates and sugars are transformed into other elements, something that human beings have used for millennia in processes such as the production of bread or pastries . They are also characterised by being a type of single-cell fungus.

1.3. Moulds

Molds are a type of fungus generally of microscopic size that are characterized by having a behavior that is usually destructive, deteriorating surfaces or living beings. They are usually made up of masses of filaments. However this does not mean that they are always negative , since in some cases they have been able to generate medicines (the clearest example being penicillin).

2. Classification according to their effect on humans

Another simple way of classifying fungi has less to do with the fungus itself than with the effects they can have on us or the usefulness we can give them. Although in this sense the classification is not so much for the entity itself but for its effects, this way of classifying them can be beneficial in order to be able to separate those that have positive effects from those that have negative ones . Among these types we can find the following.

2.1. Foodstuffs

One of the groups that usually interest the majority of the population is edible mushrooms, those that are suitable for human (or animal) consumption. Most of them are very healthy , having few calories and many proteins and vitamins. In fact, some of them are considered delicatessen, as is the case with the truffle in this country.

2.2. Toxics

In contrast to the previous one, we can also find different fungi whose properties can deteriorate our health and capacities to a great extent, or even in some cases cause our death. Unfortunately, some of them resemble edible species, which is a huge danger for those people who are not able to recognize them.

2.3. Medicines

Many mushrooms have different properties that have made them very important for the human being not only because they are or are not edible, but also because they can produce effects that allow to eliminate or control diseases. This is what happened when Alexander Fleming discovered that the mold Penicillium was capable of killing bacteria , which allowed the penicillin to be synthesized.

2.4. Parasites

Some fungi also have a parasitic behavior, feeding on the tissues of living beings.

This is the type of fungus that usually causes us diseases, often dermatological but can also occur in other tissues such as the mouth or vagina and even generate severe infections. The fungi of the Candida family are an example of this.

Another example is the fungi of the genus cordyceps, some species of which can cause suicidal behavior in insects such as ants (causing them to climb up the leaves of a plant and bite it before dying to serve as food and allow the spread of spores).

2.5. Hallucinogenic or psychoactive

Many mushrooms have been used since ancient times for their ability to generate altered states of consciousness. In some contexts they were used in religious rituals , although nowadays it is more frequent that the consumption of hallucinogenic mushrooms is done in a recreational context.

But not only that, but in many cases fungi with these properties are being studied in order to analyze possible uses in the treatment of mental or even organic disorders.

3. Ecological classification

Another way of classifying the various fungi is through their way of surviving and feeding, their function or role at the ecological level in relation to their relationship with other beings . In this sense we can find three main groups.

3. 1. Saprophytic fungi

This type of mushroom is characterized by the fact that its subsistence is based on feeding on the remains of living beings through external digestion, carried out outside the cells of the mushroom. This is one of the most relevant groups when it comes to decomposing the organic matter of corpses and feces and the time to allow the soil to remain fertile .

Some of them only receive nutrients in this way, while other fungi only use this type of nutrition during one phase of their development.

3.2. Parasitic fungi

As we have seen previously, parasitic fungi are those that base their subsistence on the dependence of a host or carrier , which can be harmed in a minor or major way by the existence of its host and for which the existence of the fungus does not suppose any type of advantage.

3.3. Symbiotic mushrooms

This type of fungus is characterized by its dependence on a subject or entity that hosts it, although the relationship with it is positive and beneficial for both organisms. For example, it is possible that the interaction between both allows both beings to feed . Within this type of fungi we can find different subtypes.

Perhaps the best known and most common case is that of mycorrhizae, in which a fungus establishes a symbiotic relationship with the roots of a plant. While the fungus feeds on the plant’s carbohydrates and vitamins, the plant obtains from these minerals and water.

Another well known example is lichens, which are born from the symbiotic interaction between a fungus and an algae . In this relationship the fungus serves as a protection for the algae, preventing environmental conditions and sunlight from drying out the algae, while the algae performs photosynthesis, and the fungus can survive thanks to the energy it provides.