Skip to content

Isopoda munnidae

The Munnidae are a family of tiny isopods with six genera and about 115 accepted species. 1 The species described in open-access studies measure roughly 0.7 to 2 mm. 2 3 4 The family is widespread in coastal environments. 2

Munnidae
Isopoda munnidae

At a glance

Data from the scientific sources listed at the bottom.

Conservation

NEDDLCNTVUENCREWEX

IUCN Red List: not evaluated.

Where it lives

The genus Munna lives mainly in cold and temperate seas, with cases in the Mediterranean too; Uromunna in temperate and tropical seas and in the cooler waters of the southern hemisphere. 2 There are tropical exceptions: Munna petronastes is recorded in Belize. 5

Life in the wild

Where it is found

Coastal environments: shell sand, seagrass beds, intertidal rocks, algae and also artificial surfaces. 2 At Ischia they were collected on algae and sandy bottoms, between about 2.5 and 48 m. 3 Munna petronastes lives between 0 and 2 m on coral reefs and rocky bottoms. 5

Behaviour

Open-access sources describe mainly their appearance, not their behaviour. In Munna males the first pair of legs can be greatly enlarged. 2

Reproduction

As in other isopods, the eggs are held in a brood pouch and a juvenile form called a manca hatches from them. 5

In the aquarium

From the experience of the BallingMania community.

Community rating

No rating in the original sheet.

Original sheet

The isopod family is very large: some species are predators, while other species are fairly harmless and are considered useful within the aquarium ecosystem. Isopoda munnidae is herbivorous and feeds on phytoplankton and microalgae; it can often be seen sitting on the rocks, on algae and above all on the glass near the water surface. It is a tiny crustacean a few millimetres long and looks very much like a white ant.

This isopod is a food source for many fish, especially wrasses and mandarinfish, but also for corals, which catch them with their polyps.

good or bad?

VERDICT:

Key: Good! An organism beneficial to the system. Reef Safe!

An organism whose benign or harmful nature is not yet known, to be kept an eye on.

Bad! The organism is a threat to the other inhabitants of the aquarium or could become a pest.

A food source for the other inhabitants of the aquarium.

A potentially toxic or venomous organism.

© Lionfish Lair · © Lionfish Lair

Did you know?

The isopods described at Ischia are white with dark dots or whitish and translucent, with eyes carried on lobes or stalks on the sides of the head. 3
Some Uromunna species live in brackish water, while all Munna are strictly marine. 2

Sources

  1. Boyko C.B., Bruce N.L., Campos-Filho I.S., Hadfield K.A., Hughes T., Merrin K.L., Ota Y., Poore G.C.B. (eds.) (2026). Munnidae G. O. Sars, 1897. World Marine, Freshwater and Terrestrial Isopod Crustaceans database, via WoRMS.
  2. Poore G.C.B. (1984). Redefinition of Munna and Uromunna (Crustacea: Isopoda: Munnidae), with descriptions of five species from coastal Victoria. Proceedings of the Royal Society of Victoria 96(2).
  3. Fresi E., Mazzella L. (1974). The genus Munna Krøyer (Isopoda: Asellota) in the Island of Ischia. Pubblicazioni della Stazione Zoologica di Napoli 39.
  4. Khalaji-Pirbalouty, Al-Kandari (2024). Uromunna alyamanii sp. nov.. Plazi TreatmentBank.
  5. Palomares M.L.D., Pauly D. (eds.) (2026). Munna petronastes Kensley, 1984. SeaLifeBase.

Sources checked on 5 November 2026. Community texts and ratings are kept separate from the scientific data.

Download the original sheet (Italian)All species