THE ANIMAL FILES

Atlantic horseshoe crab

Limulus polyphemus

A pointed tail that can help turn the body upright.

The Atlantic horseshoe crab has a horseshoe-shaped shield, underside appendages and a long tail.[1]

Follow the evidence ↓
Atlantic horseshoe crab
Image: Hans Hillewaert · Commons · CC BY-SA 4.0
Three body regions
Prosoma, opisthosoma and telson[1]
A tail with leverage
The telson can help with righting[1]
An intertidal meeting
Spawning is associated with high tides[1]

Three body regions

The body has a front region, a rear region and the long telson. Appendages beneath the broad shield move the animal and handle food.[1]

A tail with leverage

The telson contributes to steering and stability and can help an overturned animal right itself.[1]

An intertidal meeting

Adults come into the intertidal zone to spawn, with timing varying among regions. Eggs develop in sandy nests; young animals later settle and grow through repeated moults.[1]

A COMMON MIX-UP

Can the tail’s shape tell you everything about its use?

No. The telson contributes to steering, stability and righting, roles revealed by how the animal moves.[1]

TRY A LITTLE REASONING

Why should a beach survey record tide and season?

Reveal the explanation

Shore visits for spawning are linked with tidal conditions, and breeding schedules differ geographically. Comparing counts without that context can confuse timing with a difference in habitat use.[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 — Atlantic horseshoe crab (cited revision)
  2. NCBI Taxonomy — Limulus polyphemus

Last fact check: