Head to head
Giant Amphipod vs Giant Isopod
The giant amphipod and giant isopod are both textbook examples of deep-sea gigantism, but their specific size records and feeding habits differ.
| Giant Amphipod | Giant Isopod | |
|---|---|---|
| Scientific name | Alicella gigantea | Bathynomus giganteus |
| Taxonomic group | Amphipod | Isopod |
| Maximum recorded size | Over 30 cm | Around 50 cm, 1.7 kg |
| Size increase over relatives | Over 30 times typical amphipod size | Hundreds of times a garden woodlouse |
| Extreme fasting ability | Not specifically documented | One individual fasted over 5 years |
| Conservation status | Least Concern | Not Evaluated |
| Population trend | Unknown | Unknown |
| Habitat | Ocean | Ocean |
Giant Amphipod vs Giant Isopod: common questions
Which is bigger, the giant amphipod or the giant isopod?
The giant isopod is bigger in absolute terms, reaching around 50 centimetres and 1.7 kilograms, while the giant amphipod tops out at just over 30 centimetres, though both represent dramatic size increases over their much smaller shallow-water relatives.
Which species can survive longer without food, the giant amphipod or the giant isopod?
The giant isopod has the documented extreme fasting record, with one captive individual going over five years without eating, a specific endurance record not established for the giant amphipod.
Are the giant amphipod and giant isopod the same type of crustacean?
No, the giant amphipod belongs to the amphipod group, while the giant isopod belongs to the isopod group, the same broader order that includes woodlice, making them related but taxonomically distinct examples of deep-sea gigantism.