Darkling beetle

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iDarkling beetles
Heliotautus ruficollis
Heliotautus ruficollis
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Suborder: Polyphaga
Superfamily: Tenebrionoidea
Family: Tenebrionidae
Latreille, 1802
Subfamilies
  • Lagriinae
  • Phrenapatinae
  • Pimeliinae
  • Diaperinae
  • Hypophloeinae
  • Opatrinae
  • Tenebrioninae
  • Alleculinae
  • Coelometopinae

Darkling beetles are a family of beetles found worldwide, estimated at more than 20,000 species. Many of the beetles have black elytra. Darkling beetles eat both fresh and decaying vegetation. Major predators include birds, rodents, and lizards. The larval stages of several species are cultured as feeder insects for captive insectivores, and include the very commonly known mealworms and superworms, and the lesser-known mini mealworms.

Some species live in the dry Namib desert and have evolved modification that help them collect water from the fog that condenses on their elytra.

Raising darkling beetles from larvae through adulthood can be a rewarding biology project for lower school educators.


Contents

[edit] Characteristics

This family of beetles may be identified by a combination of features including

  • an 11-segmented antenna which may be filiform, moniliform, or weakly clubbed.
  • first abdominal sternite entire and not divided by the hind coxae
  • the eyes are notched by a frontal ridge.
  • the tarsi have four segments in the hind pair and 5 in the fore and mid legs. The tarsal claws are simple.
An Alleculine from India
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An Alleculine from India

[edit] Notable species

Tenebrio molitor is commonly used as food for terrestrial amniotes kept in terraria. Zophobas morio, or Superworm, is another commonly used live food insect among reptile keepers and is notable due to it being slightly larger and containing smaller amounts of chitin than Tenebrio molitor. Tribolium castaneum is a popular laboratory animal and model organism, especially in studies of intragenomic conflict and population ecology studies. These two, along with other Tribolium species (e.g. T. confusum, T. constructor) and Gnathocerus cornutus, are pests of cereal and flour silos and other storage facilities.

[edit] Rearing mealworms into adult beetles

Mealworm is a common name used for tenebrionid beetle larva. They are found in stored grain and related products. They vary in size from the very small, newly hatched larvae to final instar larvae that can be up to an inch long.

Mealworms are commonly used as feed for reptiles, fish and birds and so easy to find from supply companies.

They can be grown in a wooden box or box eight to ten inches deep. They grow best in container with large surface areas. The sides should be smooth to prevent them from escaping. The mealworms are mostly nocturnal and prefer a dark environment. Some sand may be provided at the bottom.

The food for the larvae can be flour or cereals. The temperature should be even and the box well ventilated. Some moisture can be provided by way of fruits or vegetable matter. The rearing trays are best left undisturbed. Another tray should then be provided, prepared with the same food mixture as in the first. The adults should be placed in this tray to lay eggs for more young worms. As soon as these young worms have grown sufficiently to be handled they should be put in the first tray and allowed to grow as large as desired. By using a two tray system, one should be able to provide a continuous supply of worms.

A species from India
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A species from India

[edit] External links

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