THE ANIMAL FILES

Australian box jelly

Chironex fleckeri

A transparent box-shaped bell has four tentacle clusters.

The Australian box jelly has a nearly transparent, box-shaped bell. Tentacles hang in clusters from its base, and active swimming helps it approach prey in tropical Australian coastal waters.[2]

Follow the evidence ↓
Australian box jelly
Image: Avispa marina.jpg: Guido Gautsch, Toyota, Japan derivative work: Mithril (talk) · Commons · CC BY-SA 2.0
Corners and clusters
Tentacles form four clusters.[2]
Moving towards food
It can swim towards movement.[2]
A tropical coastline
Australian records span tropical northern coasts.[2]

Corners and clusters

The bell's box-like outline gives the animal its common name. Multiple tentacles arise in each cluster rather than one tentacle accounting for the entire corner. The transparent body can be much less conspicuous than the shape in an illustration.[2]

Moving towards food

The Australian Museum describes movement towards prey and feeding on coastal prawns. The animal is therefore not simply an immobile curtain waiting for everything to drift into it; swimming is part of its feeding behaviour.[2]

A tropical coastline

The documented Australian habitat extends from Western Australia through the Northern Territory to Queensland. Coastal and estuarine settings are relevant, but a common name cannot identify every box jelly elsewhere as this same species.[2]

A COMMON MIX-UP

Is every box jellyfish necessarily Chironex fleckeri?

No. NCBI places this species within a wider box-jellyfish class containing other lineages.[1]

TRY A LITTLE REASONING

Why would active swimming change how a tentacled predator obtains food?

Reveal the explanation

It can approach prey rather than depending entirely on prey drifting to a stationary position.[2]

Sources & editorial notes

Original explanations, checked against the sources below. The image has its own credit and licence above.

  1. NCBI Taxonomy — Chironex fleckeri
  2. Australian Museum — Box jellyfish, Chironex fleckeri

Last fact check:

One discovery leads to another

Waratah anemoneA flower-shaped animal that folds with the tide.Actinia tenebrosa ↗Common liver flukeA leaf-shaped body with an active outer coat.Fasciola hepatica ↗Pork tapewormA ribbon-shaped animal with a journey between hosts.Taenia solium ↗