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Amazing vision, a powerful punch and incredibly beautiful - but not for the 'community' aquarium.
Mantis Shrimps are neither mantids nor shrimps – they are a group of 500 species in an ‘order’ of their own, the stomatopoda. This order of crustacean has been around for over 400 million years, making them very ancient indeed, but if you are tempted to think that ‘ancient’ means ‘primitive’ ….. read on! VisionMantis Shrimps have the most sophisticated vision in the animal world, far better than humans and streets ahead of even the birds. To begin with they have more than ten different types of receptor in their eyes (compared to our three), and this means that they can see far more colour and get information from wavelengths of light invisible to us. They can also see polarisation, and it is difficult for us to even imagine what that might be like. If you have ever used Polaroid glasses to look into water then you will have some idea of how useful this might be to a creature that lives in water. Not only does this ability enhance contrast, it also allows mantis shrimps to see transparent ‘invisible’ creatures and to recognise the light coming from the scales of fish. It also allows them to ‘see’ the phases of the moon and to predict the tides. EyesEach eye has three distinct parts to it, allowing the mantis shrimp to look at the same object in three different ways at once – using only one of its two eyes. Humans are rightly proud of their binocular vision, but mantis shrimps have trinocular vision in each eye. Their eyes are mounted on stalks, can move independently of one-another and are capable of the rapid, controlled jerks that allow sophisticated ‘tracking’ of movements. If our eyes were as big as theirs, relative to body size, they would be larger than footballs. Look at them! (Eyes) Packing a punchMantis Shrimps get their name from the two enormous front legs. They use these to kill their prey. Some species ‘spear’ while others ‘smash’. These limbs are incredibly powerful and Mantis Shrimps have been known to break the glass of their aquarium, which is a decidedly stupid thing to do! One Californian species can ‘punch’ with the force of a 22 caliber bullet. Add this to their ability to judge distances accurately and to track movements and you have a very efficient killing machine. Divers know them as ‘thumb-splitters’. In the aquariumMantis Shrimps can be kept in a Reef Aquarium, but since they view all other occupants as food they are best kept on their own! Here is a list of species of Mantis Shrimp suitable for the aquarium. Most species are difficult to obtain, but they will sometimes appear in a tank ‘uninvited’ with the live rock used to set up the aquarium. Two of the species that I find most attractive are the Purple-Spotted Mantis Gonodactylus smithii (Image of Purple-Spotted Mantis) and the Harlequin MantisOdontodactylus scyllarus (Image of Harlequin Mantis). So do consider keeping a Mantis Shrimp in a reef tank, but be grateful that they are relatively small and do not live on land! see also 'animal senses' and 'shrimp for the marine aquarium'. Like this? – see what else I have written.
The copyright of the article Mantis Shrimp in Marine Life is owned by John Blatchford. Permission to republish Mantis Shrimp in print or online must be granted by the author in writing.
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