Head to head
Antarctic Sea Spider vs Antarctic Krill
Antarctic Sea Spider
VS Antarctic Krill
Both are Southern Ocean invertebrates shaped by the cold, but their size, abundance, and ecological role could hardly be more different.
| Antarctic Sea Spider | Antarctic Krill | |
|---|---|---|
| Scientific name | Colossendeis megalonyx | Euphausia superba |
| Conservation status | Least Concern | Not Evaluated |
| Body size | Unusually large for a sea spider | Small, about 6 cm long |
| Lifestyle | Solitary, slow-moving predator | Swarms in the billions |
| Ecological role | Minor predator of soft-bodied invertebrates | Central to the entire Southern Ocean food web |
| Notable adaptation | Breathes through its body surface | Can shrink its body when food is scarce |
| Diet | Carnivore | Filter feeder |
| Habitat | Ocean, polar | Ocean, polar |
Antarctic Sea Spider vs Antarctic Krill: common questions
Which animal is more important to the Southern Ocean food web?
Antarctic krill is, forming the base of the food web and feeding whales, seals, penguins, and countless other predators directly, a far more central ecological role than the solitary Antarctic sea spider.
Which animal is unusually large for its group?
The Antarctic sea spider is, growing far larger than related sea spider species elsewhere, an example of polar gigantism, while Antarctic krill remains relatively small at about 6 cm long.
Which animal lives in enormous swarms?
Antarctic krill does, forming swarms that can pack tens of thousands of individuals into a single cubic metre, unlike the solitary, slow-moving Antarctic sea spider.