Carabidae
Ground Beetles are rather diverse in shape. Most adults are glossy and black, but some are iridescent, some are green, some are yellow or orange. Their bodies are usually flattened with grooves or rows of punctures running down the wing covers. They are usually a bit longer than wide, have long legs (for a beetle) and run fast. Larvae have large heads and are somewhat hairy.
This is a very large family of beetles, with over 26,000 species known from around the world, and many thousands probably not yet known. In Michigan there are as many as 450 species of Ground Beetles.
Ground beetles are found in just about any habitat that has other small animals for them to eat. They are most diverse and common in forests, but can be found on high mountains, in deserts, even on the seashore.
See page on all Beetles.
Most species in this family mature in one year, and can live for 2-3.
These beetles are only active at night. They emerge from their hiding places under rocks and logs and search for prey, sometimes climbing up into vegetation. Larvae do not come out on the surface but stay in dead leaves and the surface soil. They are solitary animals, only coming together to mate.
Mostly by taste and smell, though they have large eyes, and no doubt do a lot of touching of things.
Ground beetle larvae and adults are predators, eating other small animals. Some speciailze on a particular group (slugs for example, or caterpillars) others will eat anything they can find.
Ground beetles have their tough beetle shell for protection. They run fast, and only hunt at night. Many can give off bad-tasting chemicals. One group, bombardier beetles, can shoot out boiling hot toxic chemicals from glands on their abdomen!
A few species in this group attack seeds of corn as well as animal prey, but this is usually a minor factor.
This group of beetles is very important in controlling pests in the soil, especially the larvae of other insects.
George Hammond (author), Animal Diversity Web.