Invertebrate
Bigfin Reef Squid
Sepioteuthis lessonianaAlso known as Tiger Squid, Glitter Squid, Oval Squid, Northern Calamari
Bigfin reef squids are highly active cephalopods distinguished by a large, oval fin that wraps almost entirely around their mantle, giving them a cuttlefish-like appearance. They possess remarkable camouflage abilities, rapidly shifting their skin color and pattern through specialized chromatophores to communicate, hunt, or blend into coral reefs. These intelligent predators often gather in small schools in shallow coastal waters, using complex visual displays to coordinate social interactions and ward off rivals.
MarineColor-changingActive Hunter
—observations
—countries
—peak records
Not EvaluatedConservation statusIUCN Red List categoriesLCNTVUENCREWEXNot Evaluated — not placed on the risk ladderRed List categories, explained →
Diet & preyShrimp, Anchovies, Crabs
Predators
- Tuna
- Dolphins
- Reef Sharks
ThreatsOverfishing, coastal development, and reef degradation
HabitatsCoral reefs, seagrass meadows, and sandy shallow bays
Life span8 to 11 months
Classification
- FamilyLoliginidae
- SpeciesSepioteuthis lessoniana
Range data is not available yet.
Interaction riskLow
- Low
- Moderate
- High
- Very high
- Why interaction risk is low
- Safe to observe at a normal distance.
Responsible observation
- Night Diving: Use a red-filtered light to watch them hunt without blinding their sensitive eyes.
- Observe Camouflage: Watch quietly as they shift patterns from translucent to dark brown when approaching reef structures.
- Maintain Space: Keep a respectful distance to avoid triggering their defensive ink-jet response.
Frequent Companion (c) Paul Asman and Jill Lenoble, some rights reserved (CC BY) · cc-by
Close Relative (c) Matteo Cassella, some rights reserved (CC BY-SA), uploaded by Matteo Cassella · cc-by-sa
Image unavailableClose Relative
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