THE ANIMAL FILES

Allmouth goosefish

Lophius piscatorius

The fishing rod is part of the fish.

The allmouth goosefish is a bottom-dwelling angler with an enormous mouth, a modified fin spine used as a lure and a body that blends with its surroundings. Its early life is very different: eggs drift in gelatinous sheets before free-swimming larvae emerge.[1]

Follow the evidence ↓
Allmouth goosefish
Image: User Meocrisis on de.wikipedia · Commons · CC BY-SA 3.0
Lure
A modified dorsal-fin spine[1]
Adult setting
Mostly sandy or muddy seabeds[1]
Egg form
A floating gelatinous sheet[1]

A lure with an anatomical origin

The filaments on the head derive from modified dorsal-fin spines; the first is especially important in luring prey. A structure that looks like an accessory is therefore part of the fish’s body.[1]

Becoming part of the bottom

A broad, flattened head and fringed skin help the animal blend into places such as sand and seaweed. Paired fins can support movement along the bottom.[1]

A drifting start

Eggs lie in a thin gelatinous sheet that floats near the surface, where currents and wind can contribute to dispersal. Larvae are free-swimming before the bottom-associated adult form develops.[1]

A COMMON MIX-UP

Is the lure a separate animal riding on its head?

No. It is a modified fin spine belonging to the fish. Unusual shape does not remove its anatomical connection.[1]

TRY A LITTLE REASONING

Why might surface currents affect a species known for living on the bottom?

Reveal the explanation

Its floating egg sheets occur near the surface. Early development exposes the species to water movements different from those experienced by adults.[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 — Lophius piscatorius (adapted and translated; exact revision)
  2. NCBI Taxonomy — Lophius piscatorius (identity and game lineage)

Last fact check:

One discovery leads to another

Yellow perchA striped fish changes its menu as it grows.Perca flavescens ↗European perchStriped sides, a changing menu and a ribbon of eggs.Perca fluviatilis ↗GuppyColour can attract a mate and catch a predator’s eye.Poecilia reticulata ↗