Superworm, Zophobas morio, image by brian.gratwicke
Zophobas morio are a large species of darkling beetle which are commonly used as live food in the pet trade. They come under a range of common names, includingsuperworms, giant mealworms, morio worms and zophobas to mention a few. Despite the remarkable similarity in appearance between the larval stages of zoophobas and the more common mealworms Tenebrio molitor they aren’t actually too closely related; they aren’t even from the same genus for instance. As another interesting fact, they aren’t actually worms, they’re beetle larval stages as previously described.
Favoured over mealworms for certain animals due to their large size, super worms, morios or zophobas (I will end up using the terms interchangeably throughout this article I am sure – so apologies for that) make ideal live food for larger animals like bearded dragons, pacman frogs, water dragons, etc etc. Essentially I like to think of them very simply as extra large mealworms and treat them as such. It should be noted here that due to their increased size, zoophoba or morio worms actually carry a lower percentage of chitin which is a protein which can cause some problems with digestion in some reptiles.
Zophobas/superworms can be cultured in a very similar way to ordinary mealworms; however a little more effort is required and they whole colony cannot be maintained in a single tub for reasons we will come to later.
In its simplest form, the zophoba/ morio/ superworm colony is two containers, one which is the main colony, and a second which is compartmentalised and used to pupate the larger individuals in to the breeding beetles. Such compartmentalisation is required because zophobas will only pupate when they are in isolation
The culture tub as it shall be termed, is set up in a very similar fashion to ordinary mealworm colony whereby the substrate in the set up is also the food upon which the growing mealworms feed. The size of the tub you use is proportional to the number of mealworms you can support in your colony; the larger the better. If you want a mini (and I really do mean mini) colony then something like an empty ice cream tub will suffice. Realistically however, for a reasonably large zophoba/morio/superworm colony you will require something with a floor space of about 1x1.5ft, roughly. Height isn’t so important so long as it is at least say, 6inches. I find that storage tubs available from DIY shops are perfect for culturing your superworms.
Within this tub you should place 2-3inches of the substrate medium which will also form the food. This should be a mixture of wheat bran, porridge oats, very cheap dog biscuits (ie the cheapest money can buy, the cheaper they are the lower the protein content which is good!) and a sprinkle of yeast. The yeast supposedly helps provide certain essential amino acids which may be otherwise lacking from the diet. Any bodybuilders reading this may opt to add a small scoop of good quality whey protein instead; whey protein usually carries a very good amino acid profile.
A good idea is to powder your dry mix in a blender/coffee grinder. Creating a powdered food makes separating out the morios/superworms at a later date much much easier. If the food/substrate is powdered all you need to do is pour it through a sieve and the mealworms are effortlessly separated from their substrate and you can pick off the ones you need to feed. This is a lot quicker than rifling through the food looking for your giant mealworms/morio worms (particularly if you are hunting for tiny baby superworms)
Once you have created your mix it can be stored in an air tight container for months and simply added to the culture as and when needed.
In addition to this you can provide a few empty egg trays which the superworms/morios may well climb on and hide in – you will however find a majority are quite happy simply burying themselves in their substrate (one of the reasons you provide a few inches of the stuff). You will also find the adults congregate on these egg crates and undertake their breeding rituals and egg laying.
Superworms devouring some potato, image by wuperruper
In addition to the dry food you need to provide a source of moisture; this is something which is more dangerous than you think. Excess moisture will cause mould and bacterial growth which can destroy your colony very quickly. Mites also quickly move in to a damp colony and whilst the mites are harmless you don’t want to be feeding morio/superworms which are infested with them to your pets. The flip side however is that thirsty zophoba/morio/superworms are highly cannibalistic – so you must provide enough moisture to avoid cannibalism, but not so much that moisture can build up causing problems within the colony.
The best way to about these problems is to ensure that ventilation is extremely high in the superworm culture. This means making the lid of the culture jar 100% mesh, this means any moisture quickly evaporates and is unable to build up. In terms of providing moisture, slices of apple, potato and lettuce work well, I like to place them on top of the egg crates to as to avoid contact with the medium – this is the stuff which is most at risk of mould and bacterial growth. When you get it right, the moist food should have been devoured within 24 hours of being placed within the vivarium. Any wet food not consumed within that 24 hour window should be removed immediately and disposed of. I like to provide moist food to my zophoba/morio/superworm colony 3 times a week ensuring it is always quickly consumed.
If you find that the card board egg crates are damp or softer than usual to the touch then you quite possibly have too much moisture build up, the colony should be moved to a warmer part of the house and dried out ASAP.
Superworm adult form, image by brian.gratwicke
This is the tricky part of culturing zophoba mealworms/superworms; they will not pupate unless they are in isolation. There are a number of theories relating to why this is, ranging from stress to distribution and colonization of new areas in the wild. In a captive situation it means you must separate off the large individuals in your colony and keep them separately for pupation.
The easiest way to do this is to use a sieve on your mealworm colony to seperate the worms, and select the large individuals (1.5-2inches is usually large enough for them to pupate) separating them off. Once you have collected however many you like, these must essentially be placed in solitary confinement until they pupate.
There are a few options to do this, you essentially need a container or vessel which has been split in to lots of chambers so that each pupating superworm can be given its own ‘cell’ (we’ll continue with the prison metaphor as I quite like it...). There are lots of options for this, visit your local DIY/Discount/Poundsaver/Walmart/Angling store and look for something along the lines of a daily pill organizer
Pill organiser, image by bennylin0724
I wouldn’t actually use a pill organizer as the chambers tend to be too small – but this the kind of thing you are looking for. There are plenty of things available like this which fisher men use for keeping their bits and pieces separate; and that builders use for similar purposes. There are plenty of products which you can make use of, just ensure the chambers are large enough (1.5inch cube is a good rough measure).
Another option, and one I personally use, is empty film canisters. If you go to your local photo development store and ask nicely they will often provide you with as many as you like (I have walked out with a bin bag full of them before, I was rather overwhelmed to say the least). You are often better trying smaller independent retailers as larger chains sometimes have recycling schemes which means they are unable to give out the empty film canisters.
These empty film canisters can simply be stood up in an empty tub/box with a superworm placed in each one in its own little prison cell. You don’t need to worry about putting a lid on these, they are usually too tall to allow the mealworms to escape.
Empty film canisters are ideal, image by steakpinball
Once you have decided your means of creating your zophoba prison block, you simply take one of the large superworms you isolated from the colony and place it in its own chamber, fill your prison up with as many as you would like to pupate. One super worm per chamber. I tend to do 20-60 superworms/ at a time depending upon the size of the colony and how I am predicting future demand (ie I usually pupate more individuals late winter time in preparation of the increased demand for mealworms I will face come the spring breeding season in my reptile room).
Once in solitary confinement, you will find the superworms/morios pupate quite quickly; turning in to peculiar looking alien like critters in a matter of 3-6 days. Then within another two weeks or so they will turn in to beetles. After this they have served their prison sentence and can be returned back to the main colony to breed. It is important that you do not introduce the pupa to the colony before they have emerged as beetles; doing so puts them at risk of cannibalism (superworms have big mandibles – remember this when feeding them to your pets).
You will find the beetles breed freely, laying their eggs in the medium and upon the egg crates you placed within there. Depending upon the temperature, the eggs will take 10-18 days to hatch producing tiny morio worms. Assuming the colony receives enough food and moisture cannibalism of the eggs should not be a problem. The morio worms are slow growers, taking 6-10 months to mature, this means that breeding morios is certainly a long term commitment. However once you have a sustainable colony you can count on it being stable and highly productive for years to come. The slow growth of the colonies tends to make them quite predictable too and once you have your method and routine down (everything in this hobby is simply about maintaining good routine! Even the most difficult reptile pets can be kept easily with the correct, stringent routine).
As cold blooded animals, productivity and output of your morio/superworm colony is more or less directly proportional to temperatures. The process is controlled by fairly simply enzyme kinetics – up to a certain point productivity will increase as enzyme action within the animals increases, this increase is followed by a sharp decline at a certain temperature. This means there is an optimal temperature for optimal growth and productivity, but there is also a sharp cut off point at which the colony will soon die off.
There is another knock on affect of this; it means you can control productivity and output by carefully controlling temperatures, if the colony is growing too slowly you can increase the temperatures (and/or add more individuals, pupate more adults, etc) whereas if you are getting over run with superworms/morio worms you can reduce the temperatures. An alternative way to slow productivity is pupate fewer breeding adults, or kill off some of the current breeding adults in your colony. Do however bear in mind that these colonies grow slowly and steadily so changes to productivity may be slower to manifest compared to standard mealworm colonies (ie Tenebrio molitor colonies).
With this is mind, the ideal temperatures for good productivity in your superworm colony are 30-35c – temperatures should not be allowed to go past 38c for reasons explained above. These kinds of temperatures are easily maintained by placing a heat mat underneath the colony, or placing a spot lamp above it.
The segregated adults can be kept at similar temperatures, perhaps a little cooler at 30-32c, you can expect them to emerge as adults within about 14 days at these temperatures.
Lotsa superworms, image by mcwetboy
Superworm Cleaning & Maintenance
Cleaning is relatively straightforward. Simple use a sieve to seperate all of the mealworms in the colony (you may lose one or two of the tiniest individuals but this isn’t too much of a problem) from the medium/food which they grow in. By this point the substrate will be made up of a lot of frass (waste) so must be discarded. Simply separate the mealworms from their old substrate, dispose of the old substrate and replace it with new stuff.
I tend to perform this task about once every 3 months, however I should really do it more often and recommend you do so. In my laziness I’d rather top up the food more often and clean out less often, however this is far from optimal.
You may also wish to replace the egg crates as and when they get soiled - how often you need do this is dependant upon colony size but it is fairly simple to spot when they are soiled and ready to be replaced.
Morio worms, or superworms, or zophoba worms depending upon what you wish to call them make fantastic live food for larger reptiles and birds. They are a little trickier to breed than normal meal worms but worth the added effort due to the fact they are a hearty meal. Culture them in a similar way to ordinary mealworms, feeding a cereal and dog food based diet supplemented with fresh fruit and veg. Be very careful of moisture build up as it can quickly ruin colonies. In order to pupate adults they must be separated and placed in solitary confinement however they can be added back to the colony to breed once they are beetles.