THE ANIMAL FILES

Yellow tube sponge

No verified Chinese common name in our sources; the English name is retained.

Aplysina fistularis

A reef tube is an animal, not a plant stem.

The yellow tube sponge forms upright tubes fixed to a hard surface. Its colour can range from golden to orange-brown, and new growth depends on suitable attachment space. A broken fragment can also provide a route to a new sponge.[1]

Follow the evidence ↓
Yellow tube sponge
Image: Nhobgood (talk) Nick Hobgood · Commons · CC BY-SA 3.0
Tubes from a common base
One or several tubes rise from a closed base.[1]
A reef attachment
Hard surfaces support establishment.[1]
Two reproductive routes
Sexual and asexual reproduction both occur.[1]

Tubes from a common base

Thin-walled tubes have broad upper openings and ridged surfaces. The body remains attached rather than walking over the reef. Tube shape describes the sponge's body organisation, not a stem supporting leaves.[1]

A reef attachment

The species is recorded from Caribbean reefs. Newly formed sponges need a hard place to attach, and heavy sediment or algal cover can interfere with establishment. Available space includes the condition of the surface, not simply its total area.[1]

Two reproductive routes

Sexual reproduction produces new offspring, while a broken body piece can also develop into a new sponge asexually. Both routes depend on reaching a surface where the young sponge can attach and grow.[1]

A COMMON MIX-UP

Is the tube a reef plant?

No. NCBI places Aplysina fistularis among sponges, which are animals.[2]

TRY A LITTLE REASONING

Why could a hard rock covered in thick sediment be a poor settlement site?

Reveal the explanation

A suitable base must be accessible for attachment; surface cover can hinder establishment.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — Yellow tube sponge (cited revision)
  2. NCBI Taxonomy — Aplysina fistularis

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 ↗