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General Information

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Files And Media

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Quick Facts

  • The lava of the Tenebrio Molitor spices of beetle is known is called mealworm.

  • Mealworms are not worms they are lava!

  • Bettles live for around 8 weeks.


  • ​ It takes around 10 days for pupa to hatch into beetles depending on tempriture

  • Femail beetles lay over 500 weeks over 8 weeks

  • Mealworms can get all of there water from fruits and vegetables such as carrots and cucumbers

  • ​Pupa are the form the mealworms take as the complete metamorthpis from larva (mealworm) into a adult beetls that can breed.

  • Pupa look like aliens but cannot move only wriggle

The Tenebrio Molitor beetle is a common insect that can be found naturally all  over the world and can thrive and or survive

in most environments.

The larva of this beetle are called Mealworms. Mealworms are one of the most common insects used to feed reptiles, birds, fish and for fishing bait. Mealworms are also very commonly ate by humans outside of western countries.

Larvae typically measure about 2.5 cm or more, whereas adults are generally between 1.25 and 1.8 cm in length.

The metabolism of the insects can be slowed down by keeping them in the fridge. This method is used to stop the larva from pupating into beetles as the larva are more nutritious than the beetles. Mealworms are high in protein and there nutrient content is comparable to beef.

Mealworms are easy to keep and breed they do not smell or carry diseases. You can easily grow and maintain a mealworm coloney at room temperature feeding them a diet of only oats and carrots.

Female beetles lay around 500 eggs each over there 6 to 8 week beetle lifespan allowing for very fast colony growth.

Mealworms are not a pest spices and if any escape they will not breed or do any damage to your home or property and they are completely harmless. 


Life Cycle



The diet of a mealworm beetle is wide and varied and they are not fussy eaters requiring a specific diet. Darkling beetle and mealworm diet can be broken down in to 3 sections. Carbohydrates protein and moisture.

Carbohydrates- Bread oats and nuts are recommended as the main source of carbs for the insects. They should also be fed vegetables for extra carbs and micro nutrients.

Protein- The most overlooked part of any insect diet is protein. Many insect keepers make the mistake of giving no protein source whatsoever, this mistake leads to cannibalism and egg eating as well as less egg production and laying.

I would recommend dry or wet cat or dog food. If the food is dry it will need to be crushed first. You can also use nuts, soybeans and or egg powder.

Moisture- Insects can get all of there moisture from vegetables. I would recommend cucumber as the best source for this but almost every vegetable can be used but you should avoid citrus and acidic fruits. You could also mist to keep the insects more healthy. Bug gel could also be used but can be expensive. Bug gel will eliminate food molding.

The Tenebrio Molitor beetle has 4 life cycle stages. The time spent in the egg, larva and pupa can vary widely depending to diet humidity and temperature.

Egg- The egg stage lasts between 4 and 20 days. If the eggs are kept in the fridge or at temperatures below 10c the eggs will remain dormant and will not develop until temperatures rise.

Larva- 4 weeks or longer. The larva stage is the longest stage of the beetles life cycle. The time spent in this stage is mainly dependent on diet and temperature. The larva are known as mealworms.

Pupa- Pupa look like white aliens and are immobile while they complete metamorphosis. The pupa can wriggle. It can take as little as 6 days for pupa to hatch into beetles depending on temperature and the diet they ate in the larva stage. Pupa should be removed from larva and beetles to avoid being eaten.

Beetle- The beetle stage can last up to 8 weeks and not much longer. The beetles sole concern is eating and mating. They are most active at night. Each female beetle can lay several 100 eggs in over the 8 weeks they live.


Cleaning And Maintenance

Mealworms are easy to clean as they can

be sieved to separate them from there


Mealworm waste is called frass and is dry

with a mild smell and is safe to use as a

potent organic garden fertilizer that is far

safer than bat guano as insects are cold

blooded so cannot pass disease ect onto


When mealworm larvae are 2-3 weeks old

they are big enough not to fall threw the

holes in sieves so they and be poured from

there container and into a sieve and separated

 from the frass cleanly and easily

Beetle Info

The beetle form of the Tenebrio Molitor insect is the final adult form of the mealworm, after egg,lava and pupa.


The beetle is part of the darkling family and is small and jet black when mature. There max size is around 2.5 cm.


The mealworm beetle dose not grow and therefore douse not shed its exoskeleton, There instincts are to survive and breed so they eat less than the lava whose instinct is only to eat, store fat/nutrients for its pupa stage and grow which is why the beetle is far less nutritious than the lava and pupa but can still be fed to reptiles and chickens ect.


The beetle is fairly fast moving and very active in the daytime as well as at night spending its time eating and mating laying eggs at a rate of around 12-20 eggs per day and 500 per female beetle over there 8 week beetle stage life span.


Beetles will not breed for around 5 days after completing metamorphosis from its pupa form and will have a soft white exoskeleton for around a day which is very soft, then it turns light brown darkening gradual every day for around 5 days then its exoskeleton will be jet black and strong. It can now breed.

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