Sealife guideExplore the wonders of sea life

Last updated on 09/25/2025 at 11:32 PM

Explore the amazing biodiversity of sea life ! © Grafner | Dreamstime.com

Marine life is organized in the form of a tree, better known as a phylogenetic tree, where each branch, called a phylum, groups together marine species that share common characteristics.

An ocean sample with its marine fauna and flora

The main phyla of marine life we will explore are:

In turn, the phyla are divided into classes and families.

The different phyla are arranged from the least to the most evolved, meaning that phyla containing the least evolved marine species are represented by the lower branches of the tree, while those containing the most evolved are found at the higher branches.

Consequently, the higher we climb in the branches of the marine life tree, the more evolved the species become.

Marine plants represented by a Posidonia seagrass meadow

The spiny lobster, an arthropod of the crustacean class

The large sponge family with the yellow tube sponge !

A school of barracudas in the Mediterranean sea

If you're looking for information on a specific alga, sponge, shellfish, crab, sea star, sea urchin, sea anemone or fish, we invite you to explore the full range of marine flora and fauna in our marine life guide !

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