Water Scorpions

Water Scorpion

(Above: Laccotrephes spp. Nepidae)

Care sheet written by Butterfly_Skye (2009)

An Australia Invertebrate Forum(AIF) Publication. 2011 www.inverts.com.au © Publication is copyright of the AIF – 2011 – Greg Bylund.

Index Page 1 – Discription Page 2 – Tank set up Page 3 - Care Page 4 - Breeding & Images

Discription Water scorpions are very easy to take care of and make a very interesting and unusual addition to any invertebrate collection. Water scorpions (also called toe biters or water bugs) are not related to scorpions at all, they are a true bug and just resemble the appearance of a scorpion because they have a breathing snorkel on the tip of their abdomen. This snorkel allows them to live in still water, and water that is polluted because they do not get their oxygen from the water, they use the snorkel to breath directly from the air.

They are often found in polluted waters because nothing else will live there!

You have to be careful when handling these little buggers because they can give you a nasty bite with their raptorial arms but will also inject mild venom if given the chance. It won’t kill you but you will have a very sore finger! Water scorpions are great to watch and are most active later afternoon.

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Tank Set up As their name suggests they live in water so you will need to have a fish tank set up before you bring home your new water scorpion. I use a 10-11inch cube tank with a glass lid. You will need to have a lid because water scorpions can fly (depending on the species that you have) and are great escape artists. I prefer a glass lid because it stops the water from evaporating as quickly. The water scorpion will prefer still water, so it is not a necessity to have a filter, you will just have to do a 20% water change every 1-2 weeks (or as the tank looks dirty), but if you want a filter you can add an under gravel filter at this stage. Try to steer away from power heads or any filter that can suck the water scorpion in. Put 1-2 cm of clean gravel or river sand in the bottom of the tank and then fill it with water but leave 5-10cm gap at the top of the tank so that you water scorpion can still use its snorkel. You will need to add water conditioner to the tank. This isn’t as much for the water scorpion, but more for the feeder fish that you will need to add to the tank later! Water scorpions are good swimmers, but they prefer to hold onto things and climb around. Add some plastic plants (or real ones if you like but the water scorpion will sometimes break these apart) for your water scorpion to hang onto. They do not require a heater but if you would like them to be more active, you can add a small aquarium heater and set it to 21-22 degrees. Now you are ready for your water scorpion. You can only have 1 per tank because they will try to eat each other if they are not given enough room.

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Care Water scorpions are predators and will basically try to eat anything you put in front of them. Their food should be around 1/3 the size of the water scorpion or less, but it has to be big enough for it to grab. They will try and eat things bigger than this as well if you give them the chance! Being a water bug they will eat fish, you can purchase feeder fish (guppies) from your local pet store, I normally put 4-5 in at a time and the water scorpion will just eat them as it gets hungry. If you have feeder fish in the tank REMEMBER TO FEED THE FISH! You don’t want them to die of starvation before your water scorpion eats them. They will also eat other insects such as crickets, mealworms and cockroaches. Just hold the food item in front of the water scorpion with long forceps. It might take some getting used to but eventually the water scorpion will learn that you have the food and grab it quickly. Being a bug the water scorpion will suck out the guts of any food items and then discard the remains. You will have to remove the remains on a daily basis so that the water in the tank doesn’t get dirty. Every 1-2 weeks you will need to do a 20% water change on your tank. Tank you water scorpion out of the tank, tip out the water, re-fill the water and add water conditioner. Leave the tank to sit for a couple of hours if you can before you reintroduce your water scorpion so that the temperature of the tank can stabilise.

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Breeding It is very hard to breed water scorpions because it is hard to tell the difference between males and females. But if you are lucky enough to have one of each you will need to have them in a large tank for them to breed. They need enough space to stay away from each other so that they aren’t tempted to eat the other one, with allot of plants or driftwood that go about 10-15cm out of the water. Water temperature of 24-25 degrees will encourage them to mate.

Once they have mated, the female will lay her eggs above the water line on the plants (half in and half out so that the eggs can still breath). Some species of water scorpions will also carry the eggs on their back. It is normally the male that will keep the eggs.

(Above/Below: Giant water bug) (Lethocerus insulanus)

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