Mealworms.org – Habitat, Breeding, & Life Cycle

The mealworm is actually only a larval form of what later generates into the “Darkling Beetle”. This larval state only lasts for a couple of weeks. This worm is a very popular pet food because of the high amount of protein they hold. Pet owners of reptiles, fish, and pet birds rely heavily on these worms being mass produced to feed to their pets on a daily basis. You can visit the pages below that are devoted to different subject matters on mealworms.

image mealwormsPhysical Features & Appearance

  • Hard Exoskeleton Layer of Skin
  • Dark Yellow Color
  • Six Small legs at Front of Body
  • Two Antennae on Head
  • Head Darkens in Color with Age
  • Covered in Brown Bands

Life Cycle of The Darkling Beetle

The life cycle and transformation from worm to beetle happens in three stages. The growth starts at the worm stage and then continues to grow with molting the skin. On the last molt, the worm will turn into the “Pupa” stage. There is literally a time span of a couple weeks where the worm is changing into the beetle. In this middle stage, the worm is unable to do anything. In order for the worm to grow to different sizes and forms, it has to shed it’s exoskeleton. This shedding is known as “molting” and the mealworm will do this dozens of times before actually becoming a beetle. Visit this page for more information on the growth stages.

life cycle mealworm

After being a larva for weeks, the newest transformation is known as the “Pupa” stage. It slowly starts to change into a beetle and the process leaves the creature handicapped. It’s important for the livelihood of it to have protection and cover.

Finding & Searching for Mealworms

buying mealwormsNot all habitats have mealworms in abundance for us to go out and find. You may find it a lot easier to just purchase them from a “fishing bait” store. This worm makes for great bait when fishing for fish so tackle shops stock up on these worms in large quantities.

You can most likely purchase a couple dozen mealworms for under $5  U.S. Dollars. Or your local pet stores will most likely have them on hand for he purpose of feeding pet lizards, birds, and fish. If your in search for more of a bulk quantity, you can find large scale breeders online that sell in large quantities.

Food and Habitat

The beetle and larvae form of this insect feed on decaying debris. Mainly plant like matter such as leaves, grasses, wood matters, and more. What is dying and on it’s way out of this world will get eaten. They are referenced as “decomposers” and do a great job at it too. They will be commonly found in the darkest places burrowed up next to larger objects.

When breeding them in a controlled environment, you should feed them the best food possible. Using a substrate of oats or grains will ensure they are feeding constantly and getting lots of nutrients. They are usually bred as food for larger pet animals and the healthier they are the more nutrition the pets get out of eating them. On top of that, a healthier worm is going to breed more rapidly which in turn gives you more of them as food. You can read this thread found here for more information.

bird eating mealwormPredators and Defense

They really have no way of battling their large number of predators besides the fact of hiding. Some of it’s close cousins of the same genus have defense mechanisms though. An act where the worm stands up and gives off a predatory scent to scare away predators. Only a small amount of worms in this genus have this ability though.

Sex: Male versus Female

The human eye can’t distinguish a male versus a female. The difference in sex of this beetle larvae can only be seen with a microscope. The male will have an external organ where as the female will not. It is a bit tough for the human eye to get a clear visual on this but under a closer view it is easier to distinguish.

Food for Pets – Very Popular

What makes these worms so poplar is mostly due to the “pet industry.” People love to take care of their pets properly and a large part of that is feeding them good nutritional food. That’s where the mealworm comes in. It’s large size and ease to feed in a “dried” state makes it a great meal for our pets. Pet birds, reptiles, fish, amphibians, and some mammals benefit from eating mealworms.

A number of variables make the mealworm one of the best foods to feed these pets. It’s large body mass holds a lot of protein and nutrients for those feeding on it. The ease of being able to feed them in a “dried” state is also very convenient. Not to mention they can be shipped in large quantities across the world for a cheap price.

lizard eating worm

The reptile industry is full of pet owners that rely heavily on mealworms to feed to their pets. It is considered best to feed them as “live” food but you can also purchase them in dried form.

Sportsman and Fisherman

Mealworms are found in natural habitat around the world and just like most insects, they are heavily eaten by larger animals. Fish especially love eating this worm due to it’s larger size and bulk of protein. Fisherman have found them to be very good bait for catching fish.

Fishing anglers have found that using them as bait during certain seasons of the year works better than others. Maybe the fish just happen to have a particular appetite or they know it more as a natural food for hatches and that time of the year.


Have Anything to Add?


Posted by Alicia R: Where do you guys get your worms for feeding small pets? Petsmart’s small bottle of dried worm are over priced in my opinion.


@Reply: I buy live from petsmart. We are planning to breed our own.


@Reply: My petsmart doesn’t sell live worms unfortunately I buy them at petco. I get 100 worms for 4 bucks I believe.


@Reply: Remember that dried worms can cause constipation in small animals so you have to be careful about how many you feed them.


@Reply: Pets Plus. They have 50 live superworms for just over $4.


@Reply: say wwhaaat!

hmm I have to do my research then! soo are live worms better than the freeze dried for hedgehogs?


@Reply: Reptile store. And yes, live are 100x better than dried!!


@Reply: I feed live (breed my own, but added to my breeding colony with worms from Rainbow Mealworms), but I supplement my Beardie with dry sometimes and I but a HUGE bucket of “Happy Hens” from the feed store like IFA etc because it was extremely cheap.


Posted by Ricky K: Do your mealworms or superworms usually live longer?


@Reply: Superworms.


@Reply: Super! But I find them much harder to breed, so if you are trying to raise your own without needing to buy more, mealies are easier.


@Reply: Supers have the benefit of never morphing into beetles unless you separate them, so you can buy them in bulk rather than breeding, which is easier than trying to breed mealworms. You can also get them in sizes comparable to mealworms.


@Reply: Also more protein and easier to digest! I don’t bother with mealworms anymore, supers are just so much more awesome.


@Reply: Super worms are genetically altered for sterility and given hormones and steroids to get them that big. I wouldn’t recommend them for anything. Even reptiles.


@Reply: You’re thinking of giant meal worms. Not superworms. Superworms are an entirely different bug.


@Reply: Yes, giant mealworms are treated with hormones. Superworms are a different species that naturally get quite a bit larger than mealworms.


Posted by Keith L: Keeping mealworms in the fridge puts them in a dormant state so they don’t morph. They need to be warmed up and fed once a week, though. If you don’t refrigerate them, they’ll go between a few weeks and a few months before they turn into aliens.


@Reply: Hm. What do they eat? Can I just feed him 25 mealies between now and a week from now so I don’t have to worry about it ? lol


@Reply: A small piece of carrot, apple, or potato works best. For 25, you won’t need to put them in the fridge – you’ll have no problem going through that many before they morph.


Posted by Nick P: Has anyone tried to feed their pet aquarium fish dried meal worms wondered if they’d be any good?


@Reply: I have .. But you get a lot of mealworm ‘skins’ floating around your tank. The skin (kyten?) is not digestible, So the fish tend to spit it out.


@Reply: Where some of these worms have such a hard “shell” I think they may be hard to digest for fish. Correct me if i’m wrong though.


@Reply: The outer shell contains high level of chitin, which is largely indigestible and if not spat out it will cause a build up in the stomach which is difficult to pass. There is very very little nutritional value in meal worms when they’re alive, let alone when they’re dried as all that’s left it the outer shell.


Posted by Megan: I’m breeding these for my hedgehog and I just went to check on my worms, one pupa has started wiggling, someone said it was interesting to watch, how long does this process take for a pupa to become a beetle?

**One question i have though.. do pupes normally surface? The 8 i have found have all just been wiggling around on top, i look through the bedding and cant find any? Is it just me or?


@Reply: I am watching one morph currently, right now it’s just looks like it’s wiggling its tail, it will take a rest and then start wiggling again.


@Reply: maybe “darkling” means they turn darker as they age? Idk, i know this new one is brown and my older ones are jet black?


@Reply: The pupae also start out pretty much white (which you’ve probably noticed), but when they’re about to change the facial features and legs darken.


@Reply: I JUST FOUND 6 NEW PUPES SO FAR!!! now i’m up to 12 in my pupe home.


@Reply: I have mealie overflow but nobody lives close enough to take them off from me.


image@Reply: My pupes! And i would be excited too! My boyfriend and i’s quality time is definately going to be cut back a bit by all my worm watching i’m gonna be doing!!


Posted by Janice P: I have a pet store waiting for my farm to pick up so they can purchase their first live feeders from me (too small of a store to try and keep live feeders in 24/7, so they asked if they could make orders once the farm got going) maybe see if any of your local pet stores would do the same?


Posted by Niung: Some pupae in various stages and a beetle.


pic@Reply: The beetle will eventually turn pretty much black. Sometimes a pupa like the one at the bottom of the photo won’t quite morph all the way. That one may not. I’m not sure if the one on its back will.


@Reply: I only started with 100 mealies bc i wasnt too sure how well it was gonna work out! I have only found pupa on top of the substrate. When the pupa is doing its sit ups,its getting ready to morph..once its head actually looks like a beetle head(when u see it ull know what i mean),keep watching it!! I wanna say they usually take 20-30 mins to fully morph after that.. u kno on the pupa,how it has those lil piece that stick out,kinda where its chest is? Well that actually becomes the “wings” on the beetle!! Its really cool n im terrified of bugs lolol n no they dont fly even tho they have wings!


img@Reply: That’s a 900g ice cream tub (and it’s literally full) and I have more of the smaller mealies in another tub. This tub is turning into aliens now!


@Reply: When breeding mine I started with 300 and fed them all so had to buy more!! (i have a hedgehog and a gecko who eats them!) and what? Do they really fly? Like all the time? Orr when theyre scared? I’m going to have to think.of some way to put a lid on my new colony i started today aha! The first one is a fish tank so i’ll just use that lid!!


@Reply: I have been told that even though they have wings they can not fly.


@Reply: I had to cover my superworm beetles as they seem to fly a bit a night but I’ve never seen my darkling beetles fly.
I put a wire cover on my container with a hot glue gun, just to keep it more secure.
I have all my worms on chicken laying pellets, they seem to do much better than when I had them on oats/bran.


Posted by Keith R: I need to be careful with what i feed them as my gecko is getting them as well and i’m iffy on what to feed the mealies that he gets fed as i found before i started a farm, that if i got mealies from certain stores, he’d throw them up, not sure if its what they ate or what .. but i domt wanna have a mealworm farm right above my geckos viv and not even be able to reach down and feed him some if they make him sick?! i keep mine on germ as well which tends to be smaller than bran and oats, and i find the mealies eat ot before anything else


@Reply: I use the feed for substrate/food and I give all my bugs collard greens, carrots or potato for food/water.


@Reply: I have mine on wheat bran or normal porridge oats. They eat it all up and all that’s left is dust (poo) on the bottom of the tub. I found carrots are the best although they go crazy over apples and cucumbers too. Spinach leaves are another good one.