Domain: Eukaryota
(unranked): Diaphoretickes
(unranked): Archaeplastida
(unranked): Viridiplantae
Division: Chlorophyta
Class: Ulvophyceae
Order: Cladophorales
Family: Pithophoraceae
Genus: Aegagropila
Species: A. linnaei
Binomial name: Aegagropila linnaei
Common names: Marimo moss balls, Moss ball, Lake ball, Marimo, Cladophora ball, Mossimo

 Contact the Ministry of Primary Industries Freephone: 0800 00 83 33

Aegagropila linnaei is a species of filamentous green algae (Chlorophyta) found mostly in a number of lakes in the northern hemisphere. Marimo moss balls are a rare growth form where the algae grow into large green balls with a velvety appearance. The algae grow into sizable balls of densely packed algal filaments that radiate from the centre. They found mostly in lakes in the northern hemisphere.
In 2015-16 a 38-year-old Brazilian woman who lives in New Zealand imported them and sold them in terrariums as part of her Arte Viva Living Art venture in Christchurch. In 2018 she was prosecuted for importing the potentially invasive algae. The Ministry of Primary Industries has been able to trace all but three of the buyers of these terrariums. The three moss balls that remain out in the community have the potential to ruin the New Zealand lakes and rivers. The untraced owners need to hand in their terrariums to MPI before another destructive didymo-type biosecurity outbreak happens. A refund will be given.
Contact the Ministry of Primary Industries Freephone: 0800 00 83 33

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Thanks to Wikipedia for text and information:https://creativecommons.org/licenses/by-sa/3.0/