Species · GBIF taxon 9607299
Austruca perplexa
austruca perplexaAlso known as Perplexing Fiddler Crab, Perplexed Fiddler Crab
Perplexing fiddler crabs are highly social, burrow-dwelling crustaceans that populate tropical and subtropical mudflats. Males possess a single, enormously enlarged major claw used in rhythmic waving displays to attract mates and defend territory against rivals. As the tide recedes, these active crabs emerge in vast numbers to feed on organic detritus, retreating rapidly to their burrows at the slightest sign of danger.
CrustaceanIntertidalSocial
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & prey
- Detritus
- Microalgae
- Bacteria
Predators
- Shorebirds
- Predatory fish
- Larger crabs
ThreatsCoastal development, habitat destruction, and water pollution
HabitatsIntertidal mudflats, mangrove forests, and sandy estuaries
Life span1 to 3 years
Size / weightNot available
Classification
- OrderDecapoda
- FamilyOcypodidae
- GenusAustruca
- Speciesaustruca perplexa
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Males can deliver a minor pinch with their large claw; observe them from a distance.
Responsible observation
- Approach slowly: Walk softly on mudflats as they are highly sensitive to ground vibrations and shadows.
- Watch the wave: Use binoculars to observe the distinct waving patterns males use to signal females.
- Respect the burrows: Avoid stepping on the small, round burrow entrances during low tide.
Competitor Bernard DUPONT from FRANCE / CC BY-SA 2.0 · cc-by-sa
Close Relative (c) 如此甚好, some rights reserved (CC BY) · cc-by
Image unavailableClose Relative 
Distant Relative (c) Kathy Richardson, some rights reserved (CC BY) · cc-by
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