Marimo Exhibition Center in Lake Akan, Kushiro

1. Birth

Formation and germination of zoospore

The Marimo produce zoospores around June.
The zoospore beats two flagella and swims in the water.
It eventually attaches on pebbles and rocks, and germinates.
Live Introduction : Birth of Marimo
Under the Marimo tank : Germinated Marimo’s zoospores

2. Growth

Growth into filament

The germinated zoospore grows into a string-like shape with branches.
This is called filament, which is the individual form of Marimo.
Live Introduction : Filamentｓ of Marimo

3. Dense growth

Aggregation of the filaments

The filaments develop as if covering a pebble.
These also grow densely on rocks.
The filaments exfoliated from the rocks sometimes form small masses by rolling movement of wave.

4. Formation of ball

Formation of spherical Marimo

Masses of the filaments gradually grow into large spherical shape, rotating on the lake bottom by wave motion.

5. Gathering

Community formation of spherical Marimo

According to a singular stream, many spherical Marimo are brought together in the same place, and form the pure community.
Marimo tank : Marimo habitat

6. Dissolution

Cavity formation following growth increase

The Marimo which grew largely forms a cavity in the inside, and eventually the aggregation results in collapse.

7. Regeneration

Fragments of the collapsed Marimo grow and often regenerate spherical aggregations.