Insects · Coleoptera · Tenebrionidae

Yellow Mealworm Beetle

Tenebrio molitor

Not Evaluated

It has not yet been assessed against the IUCN criteria. See full glossary

A black beetle whose larvae, the mealworms, are yellowish with a hard, segmented body. It feeds on flour, bran, grain and decaying plant matter. It is farmed on a large scale as animal feed and, for the past few years, for human consumption.

Size

12 cm – 18 cm

Diet

Omnivore

Combines animal and plant food depending on availability.

Activity

Nocturnal

Active mainly at night.

Social structure

Colony

Lives in large concentrations, often for breeding reasons.

Sighting difficulty

Unknown

GrasslandOmnivore Nocturnal Colonial Insect Grassland

6countries

Fun facts

In 2021 it became the first insect authorised by the European Union as human food, following a favourable opinion from the European Food Safety Authority.
Its larvae can digest expanded polystyrene thanks to bacteria in their gut and turn it into biomass, an open line of research for treating plastic waste.
It is one of the most widely used insects in the laboratory and in feeding reptiles, birds and fish, thanks to how easy it is to rear.
It was the first insect authorised as a novel food in the European Union: EFSA issued a favourable opinion on the dried larva in January 2021.
The in vitro digestibility of its protein reaches 91-99 %, slightly above even that of the house cricket.
Oven drying reduces that digestibility, and so does cutting the chitin content, although less so.
Like the cricket, it triggers cross-reactions in people allergic to crustaceans and dust mites.
Farming it has a far smaller environmental impact than conventional livestock in feed conversion, emissions, and water and land use.