---
title: Red-spotted Guard Crab (Trapezia tigrina)
scientific_name: Trapezia tigrina
common_name: Red-spotted Guard Crab
taxon: Crabs
published: 2023-12-22T23:54:32.796Z
updated: 2026-08-13T21:02:54.596Z
tags: Red-spotted Guard Crab, Trapezia tigrina, Crabs, Red Sea, Marine Life, Diving
url: https://redseacreatures.com/taxon/invertebrate/crustaceans/crabs/red-spotted-guard-crab
---

# Red-spotted Guard Crab (*Trapezia tigrina*)

## Quick facts

- **Group:** Crabs (*Brachyura*)
- **Size:** up to 2.5 cm
- **Depth:** 1-20 m
- **Diet:** Omnivore
- **Activity:** Nocturnal
- **Rarity:** Common
- **Habitat:** Wedged among the branches of Pocillopora and Acropora colonies
- **Reproduction:** Egg layer, Gonochoric

## How to recognise it

- small flat crab, cream to orange with fine red spots
- deep among the branches of a live coral head, never on open rock
- one pair per colony, and they do not leave it
- width up to 2.5 cm

A small spotted crab wedged between the branches of a living coral, where it stays for life. Look into any healthy Pocillopora head and there is usually a pair in there, and their presence changes what happens to that colony.

They defend it. When a crown-of-thorns starfish climbs onto a coral head, the crabs come out and go for the tube feet and the spines, pinching and pulling until the starfish moves off - and a colony with guard crabs in it survives attacks that strip a colony without them. They do the same against feeding snails and against smothering sediment, which they clear branch by branch.

The coral pays them. The crabs live on the fatty mucus it secretes and on the tissue caught in it, and they get shelter no predator can reach into. Neither partner does well alone: guard crabs removed from a colony rarely survive, and colonies without crabs are eaten.

They are also territorial about it. One pair holds a coral head and drives off other crabs, which is why a colony has residents rather than a crowd.

## Also known as

- **English:** red-spotted guard crab
- **Italian:** Granchio guardiano a punti rossi
- **Spanish:** Cangrejo Paladín Pantera
- **Portuguese:** Caranguejo-cardinal-morango
- **Japanese:** アカホシサンゴガニ
- **Chinese:** 虎斑梯形蟹
- **Russian:** Трапеция тигровая

## Scientific synonyms

- *Trapezia danae* Ward, 1939
- *Trapezia danai* Ward, 1939
- *Trapezia punctata* Coulon, 1864
- *Trapezia wardi* Serène, 1971

## Range

Indian Ocean, Mozambique Channel, Red Sea, Seychelles, South Pacific Ocean, Western India

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*Source: [Red Sea Creatures](https://redseacreatures.com/taxon/invertebrate/crustaceans/crabs/red-spotted-guard-crab)*
*Updated: August 13, 2026*