# Mantis Shrimp — Facts, Threats & Conservation *Order Stomatopoda — around 500 species, including Odontodactylus scyllarus* > Mantis shrimp are stomatopod crustaceans whose raptorial strike is fast enough to vaporise water and produce a cavitation shockwave, and whose eyes carry up to sixteen photoreceptor types plus polarised-light vision. **IUCN status:** Order page — most species unassessed · **WARN range:** Tropical and subtropical shallow seas worldwide, Reefs, rubble and burrows in soft sediment ## Quick facts | Fact | Value | | --- | --- | | Described species | ~500 | | Strike speed | ~23 m/s in water | | Secondary effect | Cavitation bubble collapse | | Photoreceptors | Up to 16 types | | Polarised light | Detects both linear and circular | | Two forms | Smashers and spearers | ## Scientific classification - **Kingdom:** Animalia - **Phylum:** Arthropoda - **Class:** Malacostraca - **Order:** Stomatopoda - **Notable species:** Odontodactylus scyllarus (peacock mantis shrimp) ## Conservation status - **Status:** Varies by species — order page - **Population:** Not applicable at order level - **Trend:** Unknown for most species - **Assessed:** Very few species assessed - **CITES:** Not listed - Reef degradation and collection for the aquarium trade are the documented pressures, though most species have never been formally assessed. ## Key facts: Mantis Shrimp - Mantis shrimp are stomatopods, not true shrimp. - The strike is fast enough to vaporise water, producing a second shockwave on bubble collapse. - Smashers club hard-shelled prey; spearers impale soft prey. - They have up to sixteen photoreceptor types and see polarised light. - More receptors does not mean finer colour discrimination — evidence points to faster recognition instead. ## The strike Smasher mantis shrimp store energy in a saddle-shaped spring in the appendage and release it in a latch-mediated snap. The club accelerates at a rate comparable to a small-calibre bullet, reaching around 23 metres per second in water. The speed drops local pressure enough to vaporise water, forming a cavitation bubble. When that bubble collapses it releases a second burst of energy, along with light and heat. Prey is therefore struck twice — once by the club, once by the implosion — which is how a mantis shrimp opens crab shells and, in aquariums, cracks glass. ## Two toolkits Stomatopods split into two broad strategies. Smashers carry blunt clubs for battering hard-shelled prey: crabs, snails and molluscs. Spearers carry barbed, folding appendages for impaling soft prey such as fish and shrimp, striking with the same latch mechanism but a different tip. The club is a material of considerable engineering interest. Its layered, helical structure resists the enormous repeated impacts without shattering, and it has been studied directly as a model for impact-resistant composites. ## The eyes, accurately described Mantis shrimp eyes are mounted on stalks, move independently, and each eye has trinocular depth perception on its own. They carry up to sixteen photoreceptor types spanning ultraviolet into the visible range, and can detect both linear and circular polarised light — the only animals known to do the latter. The popular claim that they therefore see unimaginably rich colour appears to be wrong. Behavioural tests showed they discriminate similar wavelengths less finely than humans do. The favoured explanation is that they recognise colour directly at each receptor rather than by comparing across receptors, trading precision for speed — useful for an ambush predator that must identify a target instantly. ## Behaviour and keeping Many species are territorial and hold burrows, and some form long-term monogamous pairs. They are intelligent by invertebrate standards, learning to recognise individual neighbours by sight and smell. In the aquarium trade they are prized and problematic in equal measure: a smasher can break tank glass, and they will kill tankmates. Responsible keeping means a species-appropriate solo tank with acrylic or thick glass, which is a specialist commitment rather than a casual one. ## What WARN does WARN publishes free, sourced species education including where popular claims and the underlying research diverge. The mantis shrimp's colour vision is one of the most confidently repeated wrong facts on the internet, and correcting it is more interesting than the myth. If this guide helps you understand wildlife and the pressures it faces, a gift to WARN supports habitat protection and free public education in our partner countries. ## Frequently asked questions: Mantis Shrimp ### How powerful is a mantis shrimp punch? The club of a smasher accelerates to around 23 metres per second in water, fast enough to drop local pressure and vaporise water into a cavitation bubble. When that bubble collapses it delivers a second shockwave, so prey is hit twice. A mantis shrimp can break aquarium glass. ### Can mantis shrimp see more colours than humans? Not in the way usually claimed. They have up to sixteen photoreceptor types against our three, but behavioural tests showed they discriminate similar wavelengths less finely than we do. The evidence suggests they recognise colour directly at each receptor for speed rather than comparing across receptors for precision. ### Are mantis shrimp actually shrimp? No. They are stomatopods, a separate order of crustaceans that diverged from true shrimp and prawns hundreds of millions of years ago. ### What is the difference between smashers and spearers? Smashers have blunt clubs for battering hard-shelled prey such as crabs and snails. Spearers have barbed, folding appendages for impaling soft prey such as fish. Both use the same spring-and-latch mechanism with a different tip. ### What do mantis shrimp / stomatopods eat? Mantis Shrimp / Stomatopods eat Cavitation — The strike creates a bubble whose collapse hits prey a second time. Mantis shrimp are stomatopod crustaceans whose raptorial strike is fast enough to vaporise water and produce a cavitation shockwave, and whose eyes carry up to sixteen photoreceptor types plus polarised-light vision. ### Where do mantis shrimp / stomatopods live? Mantis Shrimp / Stomatopods live in Tropical and subtropical shallow seas worldwide, Reefs, rubble and burrows in soft sediment. Mantis shrimp are stomatopod crustaceans whose raptorial strike is fast enough to vaporise water and produce a cavitation shockwave, and whose eyes carry up to sixteen photoreceptor types plus polarised-light vision. ### Are mantis shrimp / stomatopods dangerous? Mantis Shrimp / Stomatopods are not generally dangerous to people. Mantis shrimp are stomatopod crustaceans whose raptorial strike is fast enough to vaporise water and produce a cavitation shockwave, and whose eyes carry up to sixteen photoreceptor types plus polarised-light vision. Give wild individuals space and do not corner or handle them. ### How long do mantis shrimp / stomatopods live? A precise wild lifespan for mantis shrimp / stomatopods is not firmly established in the sources cited on this guide. Mantis shrimp are stomatopod crustaceans whose raptorial strike is fast enough to vaporise water and produce a cavitation shockwave, and whose eyes carry up to sixteen photoreceptor types plus polarised-light vision. Where longevity figures appear in the literature they vary by region, sex and whether animals are wild or captive. ### How big is a mantis shrimp / stomatopod? Mantis shrimp are stomatopod crustaceans whose raptorial strike is fast enough to vaporise water and produce a cavitation shockwave, and whose eyes carry up to sixteen photoreceptor types plus polarised-light vision. ## Sources - [Smithsonian Ocean — Invertebrates](https://ocean.si.edu/ocean-life/invertebrates) - [IUCN Red List](https://www.iucnredlist.org/) --- Full guide: https://worldanimalrescuenetwork.org/wildlife-guides/mantis-shrimp