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TENEBRIONOID BEETLES

TENEBRIONOIDEA

T

enebrionoidea is the fourth largest of the

beetle superfamilies, exceeded only by the

“big three” of Staphylinoidea, Chrysomeloidea,

and Curculionoidea. It includes over 33,000

species in more than 3,000 genera and 28 families.

Tenebrionoids are not well represented in the fossil

record, but undoubted tenebrionoid fossils are

known from at least the Middle Jurassic, about

170 million years ago. Most of the diversity of the

superfamily consists of the darkling beetles (family

Tenebrionidae) with over 20,000 species, but many

of the smaller families are ecologically and

behaviorally interesting.

A large number of them are associated with

forests, with larvae developing in dead wood, tree

fungi, or as predators under the bark of trees. In

fact, 24 of the 28 families have representatives partly

or entirely associated with this habitat. Many

wood-feeding tenebrionoids play an important role

in forest health, and several are of conservation

importance in the much-decreased forests of

Europe and North America. In many forest species,

the larval stage is much longer than the adult life,

so adults are rarely seen.

The smallest Tenebrionoidea are the tiny Ciidae

(usually less than 2 mm long), which bore in hard,

woody bracket fungi, sometimes in huge numbers.

The largest are the Trictenotomidae, a small family

of sometimes metallic beetles from tropical and

subtropical Asia. Reaching 31/2 in (9 cm), with long

antennae and large mandibles, they are easily

mistaken for Cerambycidae or even stag beetles.

Like almost all adult tenebrionoids, they can be

recognized by the structure of their tarsi (feet),

which have one fewer segment on the back legs.

superfamily

Tenebrionoidea

known species

33,727

distribution

Worldwide except Antarctica

habitat

Most habitats, from dry deserts to the edges

of glaciers. Many species are associated

with forests. Some have moved into stored

products and even human habitations

size

1–80 mm

diet

The diet varies profoundly, but very few

Tenebrionoidea feed on living plants. Many

are predatory as larvae, but almost none as

adults. Adult Tenebrionoidea often feed on

pollen and nectar, fungi, and dead plant

and animal matter, or in some cases do not

eat at all

TENEBRIONOIDEA —Tenebrionoid Beetles

left | Glipa malaccana (Mordellidae)

Tumbling Flower Beetles, this one

from Asia, leap, then drop to the

ground if disturbed.