Classification of Thallophyta

Thallophytes are biologically classified into; Algae, Lichen, and Fungi

Alage

Algae are mainly aquatic organisms (freshwater or marine). They are autotrophic and are capable of synthesizing their food. They bear chlorophyll for photosynthesis. The forms and sizes of algae vary. The size of algae ranges from microscopic structures (Chlamydomonas), filamentous (Spirogyra), and massive (Kelp) to colonial (Volvox) forms. They possess flexible bodies which enable them to move with the tides. Their bodies are usually covered by mucus. They can be classified into;

1. Rhodophyceae: They are also called red algae due to their reddish appearance. They are mostly marine. They contain chlorophyll a, d, and phycoerythrin. They store their food in the form of floridean starch. Examples are; Porphyra, Polysiphonia, Gelidium, and Gracilaria.
2. Phaeophyceae: They are also called brown algae due to their brownish appearance. They are mostly marine. They contain chlorophyll a, c, and fucoxanthin. They store their food in the form of mannitol and laminarin. Examples are; Fucus, Dictyota, Laminaria, and Sargassum.
3. Chlorophyceae: They are also called green algae due to their greenish appearance. They are found in freshwater, brackish water, and marine environments. They contain chlorophyll a, and b only. They store their food in the form of starch. Examples are; Chlorella, Volvox, and Ulothrix.

Lichen

It is formed when a symbiotic association between algae and fungi takes place. The algal or cyanobacterial partner is called phycobiont and is responsible for the photosynthesis and synthesis of food. The fungal part is called mycobiont and is responsible for providing anchorage, protection, minerals, and water. Examples are; Crustose lichen, Foliose lichen and Fruticose lichen.

Fungi

They are non-motile, heterotrophic, spore-bearing, non-vascular plant-like organisms. The fungal cell wall is made of chitin, glucans, and glycoproteins. Their body is composed of finger-like projections called hyphae. A network of hyphae is called mycelium. They lack chlorophyll or any other photosynthetic pigments. Hence, they are dependent on other organisms for food as they live as parasites, saprophytes, or symbionts. They can be classified into;

1. Phycomycetes: They are mostly saprophytic or parasitic. Their hypothesis is unbranched or aseptate. Examples are; Mucor, Rhizopus (bread mould) and Albugo.
2. Ascomycetes: They are mostly saprophytic, parasitic, or coprophilic. Their hyphe is branched or spetate. Examples are; Aspergillus, Claviceps, Penicillium,, and Neurospora.
3. Basidiomycetes: They are mostly saprophytic or parasitic. Their hyphe is branched or septate. Examples are; Agaricus (Mushroom), Ustilago (Smut fungus), and Puccinia (Rust fungus).
4. Deuteromycetes: They are mostly saprophytic or parasitic. Their hyphe is branched or spetate. Examples are; Alternaria, Colletotrichum and Trichoderma.

Note: Lichens and fungi are currently not placed under Thallophyta. Due to their characteristics Fungi have been assigned a new kingdom of their own i.e. Kingdom Fungi and Lichen viruses are not placed under any kingdom.

Thallopahyta are also known as Thallophyto and Thallobiont. Thallphyta belongs to the plant kingdom. The name “Thallophyta” comes from the characteristic feature of the “thalloid body” i.e. undifferentiated body. Thallophytes are the most primitive form of plants, mostly found in damp areas or near water bodies. In this article, we will study Thallophyta, its characteristics, and the importance of Thallophyta.