CRYPTOGAMIC PLANTS: MOST RELEVANT CHARACTERISTICS - BIOLOGY - 2024

The cryptogamic plants are those that reproduce by spores. The term comes from the Greek and means "hidden reproduction", indicating that these plants are not produced by seed; this denomination represents the plants that do not have seeds.

Cryptogams contain so-called "lower plants" that do not have the structures normally possessed by other plants, such as true stems, roots, leaves, flowers or seeds, and their reproductive parts are hidden.

In the broadest sense, the word cryptogam refers to organisms whose reproduction occurs through spores, not seeds.

Consequently, it is interesting to note that the cryptogams group also contains other organisms that are not part of the plant kingdom.

Examples of organisms contained in cryptogams include cyanobacteria, green algae, some fungi, and lichens.

All these organisms belong to different kingdoms. This indicates that the cryptogamic grouping is artificial and not taxonomic.

Main features

Reproduction

As mentioned above, cryptogams do not have the same structures as most common plants, and their reproductive parts are hidden.

Some cryptogams only reproduce asexually through spores, which means that they do not need another organism to reproduce.

Other types of cryptogams have generations that alternate between asexual reproduction and sexual reproduction, the latter through the union of male and female gametes from different organisms.

Habitat

Cryptogams can live in aquatic environments or on land. However, those that are terrestrial are more frequently found in shady or humid environments. Most cryptogams need a humid environment to survive.

Ferns are the only cryptogams that contain a vascular system to transport fluids and nutrients within the body, so the other groups of cryptogams require an external source of water in order to survive and grow.

Nutrition

Some cryptogams are capable of photosynthesis, which means they can make their own food. Organisms that are capable of producing their own nutrients are called autotrophs.

Other members of the cryptogams depend on external sources to obtain food, these are known as heterotrophs.

Some of these organisms directly absorb nutrients from others. Also, there are organisms that obtain nutrients from dead organic matter.

Cryptogams are clearly a very diverse group of organisms, making it difficult to create a set of characteristics that apply to all members of this group.

The 3 main types of cryptogamic plants

1- Talophytes

This group includes plants that have a structure called thallus that does not differ in roots, stems, or leaves.

For this reason, they are also known as lower plants because of their relatively simple anatomy.

The talofitas constitute a polyphyletic group; This means that the organisms that comprise it do not come from a single common ancestor, but from several.

Algae (kingdom plantae), fungi, and lichens (kingdom fungi) belong to this group.

2- Bryophytes

The term bryophyte comes from the Greek and is used to refer to a group of very small plants that do not have a vascular system; that is, they do not have specialized structures to conduct water and nutrients.

They are terrestrial plants but require a lot of humidity to survive and to reproduce sexually.

Bryophytes also comprise several classes including mosses, liverworts, and anthracites.

3- Pteridophytes

Pteridophytes are the most evolved cryptogams since they are the first group of terrestrial plants with a vascular system, xylem and phloem, for conducting water and nutrients, respectively.

The body of these plants is differentiated into roots, stems, and leaves. The species of this group are widely distributed in tropical environments and in humid mountainous areas.

According to their anatomy, pteridophytes are subdivided into 4 classes: psilopsida, lycopsida, sphenopsida, and pteropsida.

References

1. Awasthi, D. (2009). Cryptogams: Algae, Bryophyta and Pteridophyta (2nd ed.). Krishna Prakashan Media.
2. Reddy, S. (1996). University Botany: Algae, Fungi, Bryophyta and Pteridophyta, Volume 1 (1st ed.). New Age International.
3. Sharma, O. (2014). Bryophyta: Diversity of Microbes and Cryptogams (1st ed.). McGraw-Hill Education.
4. Singh, V., Pande, P. & Jain, D. (2004). Text Book of Botany Diversity of Microbes and Cryptogams (3rd ed.). Rastogi Publications.
5. Smith, G. (1938). Cryptogamic Botany, Volume 1: Algae and Fungi (8th ed.). McGraw-Hill publications Book Co., Inc.
6. Strasburger, E., Lang, W., Karsten, G., Jost, L., Schenck, H., & Fitting, H. (1921). Strasburger's Text-book of Botany (5th ed.). London, Macmillan.