Marine Isopod

Creature Feature – Isopod

This week is the letter ‘I’, and today’s featured creature is the Isopod.

Isopods are an order of invertebrates that belong to the greater crustacean group of animals, which also includes crabs and shrimp. It is estimated that there are around 10,000 species of isopod, around half of which live in our oceans.

Marine isopod


Kingdom: Animalia

Phylum: Arthropoda

Class: Malacostraca

Suprerorder: Peracarida

Order: Isopoda

Isopod Fact File

? Size: Most species reach lengths of between 0.7mm and 3.5cm however a giant marine species can grow up to 35cm in length. These giants can weigh up to 1.8kg

? Distribution: Species can be found across the globe, inhabiting varying ocean zones e.g., abyssal (deep ocean) as well as in freshwater e.g., estuaries

? Diet: Isopods have a simple gut which lacks a midgut section. Food is sucked into the oesophagus and passed into the stomach. They have a varied diet depending on species – they can be detritivores (decomposers), carnivores, filter feeders, and parasites

? Behaviour: Crawling is the primary means of locomotion, and some species bore into the seabed, the ground or timber structures

? IUCN Status: There is little data regarding the conservation status of almost all marine isopods. However, studies show a large migration of some isopod species which is believed to be a direct response to warming sea temperatures