Depending on your source of information, there can be anywhere from 12,000
to 20,000 species of the Tenebrionidae family which make up the group known as
Darkling Beetles. Encyclopedia Britannica gives us this definition:
"Darkling Beetle -- any member of the
approximately 12,000 species of the insect family Tenebrionidae (order
Coleoptera), so named because of their nocturnal habits. "
The immature larval stage of these beetles are known as mealworms.
Darkling Beetle Information Darkling Beetle Pictures
Species: T. molitor
As an adult, the darkling beetle has a black body with hardened front wings and an eleven segmented antenna. Its head is visible when viewed from above. As larva, the darkling beetle is called the
mealworm. The mealworms are about an inch in length and have a tough yellowish brown exoskeleton and are cylindrical. The mealworm has six small jointed legs, brown bands around their bodies and two antennae.
Beetles are found under rocks and logs and in animal burrows. Inside the home they are found in cabinets and pantries where cereal and grains are stored, in cornmeal, flour, cake mixes, meat scraps, around dead insects and in bran and litter from chicken houses. They are also found in termite and ant nests. Darkling Beetles eat both fresh and decaying vegetation including leaves, sticks, grasses and new plant growth. They also eat dead insects, feces and stored grains.
Darkling Beetles go through complete metamorphosis during its life cycle. At the beginning of the mating process, the male chase the female until she gives up. He then mounts her and curls his tail underneath him and inserts. The female then burrows in soft ground and lays 275 tiny white oval eggs that hatch into mealworms.
Larvae are wormlike and hardened for burrowing. The mealworm molts up to 20 times and grows into the pupa stage. During this stage they do not eat. In the pupa stage they are ˝-3/4 inches long and white but darkens before the beetle emerges. Newly hatched beetles will sit still as its wings unfold and dry. After changing colors from brown to black it searches for a mate and only lives for a few months. The life cycle lasts three to five months.
Predators of mealworms and darkling beetles are birds, rodents, lizards, predatory beetles and spiders. When disturbed, some darkling beetles assume a defensive posture where they stand on their head and release chemicals from scent glands in their rear-end that produces noxious odors and can turn skin brown. They prefer darkness and like to have their body in contact with a nearby object. Mealworms are also known as the Superworm because they are used as a food source for reptile pet and in bird feeders. The Yellow Mealworm is known as the “golden grub” and is used primarily for fish bait. Mealworms have also been put into tequila flavored candies.
Credits: A big thanks to Lani Powell for researching and writing this
Darkling Beetle Information article!
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