Group 4

Group 4 is made up of algae whose chloroplasts are surrounded by a double membrane of chloroplast E.R. This group is also called Chromista. Compared to the other groups, this one has the most subgroups (phyla), which include the following:

• Cryptophyta – Members of the Cryptophyta are often found in freshwater environments (but can also be found in marine habitats). They have chlorophylls a and b, just like a lot of other algae. Most of the time, though, they have a flattened shape and a groove on the front.
• Heterokontophyta – The plants in this group are called heterokonts, and their sizes vary a lot. Kelp, which has many cells, and diatoms, which only have one cell, are both in this group. They also have chlorophyll a and b and a flagellum to help them move.
• Prymnesiophyta -Members of the Prymnesiophyta have two flagella to move and chlorophylls a and c to make food. They have fucoxanthin that looks like scales and is outside the cell.
• Phaeophyceae – Phaeophyceae are brown algae with many cells. They are usually found in cold seawater in the Northern Hemisphere.
• Chrysophyceae – Chrysophyceae are algae that are usually golden brown and live in fresh water. They also have two flagella that help them move.
• Phaeothamniophyceae – Members of this group are golden brown and can look like filaments, coccoid shapes, or fake filaments.
• Synurophyceae – Some members of the Synurophyceae have four membranes around them. Fucoxanthin, chlorophyll a and c, and chlorophyll c are also traits of these algae, which are usually found in fresh water.
• Xanthophyceae – Xanthophyceae are algae that are usually found in fresh water and are yellow-green. Some species, though, can also be found in other places (marine and soil). Movement is made possible by a single flagellum or, in some cases, by structures that look like threads.
• Eustigmatophyceae – This is a small group of plants that live in many different places (freshwater, marine, soil). This group is also made up of organisms with only one cell and a polysaccharide wall around it. Raphidophyceae: Also called chloromonads, these plants can be found in both fresh water and salt water. Organisms with one cell or more than one cell but no cell walls are also made up of parts.
• Raphidophyceae –  Also called chloromonads, these plants can be found in both fresh water and salt water. Organisms with one cell or more than one cell but no cell walls are also made up of parts.
• Pinguiophyceae – Pinguiophyceae is a group of marine organisms that are made up of single cells. They have a lot of fatty acids with a chain of hydrocarbons that has several carbon-carbon double bonds.
• Bacillariophyceae – Bacillariophyceae are made up of diatoms, which can be found in places like soil and the ocean.
• Dictyochophyceae – Members of this small group, which are also called silicoflagellates, are often found in marine environments and use their flagella to move from one place to another.
• Bolidophyceae – This group, which has about 20 known species, is made up of aquatic organisms with flagella that are set at an angle.
• Pelagophyceae – Pelagophyceae are made up of heterokont algae that are usually found in the ocean. They also include single-celled and multi-celled organisms that move with the help of flagella.