Other Common Names
Spanish: insectos, insecta
Explanation of Names
Latin insectum, pl. insecta "cut into, cut up" (refers to body segmentation), a literal translation of Greek entomos (εντομος)
Worldwide, 25-30 extant orders (+ ca. 10 extinct), depending on authority, up to 1000 families, and well over a million species
In our area (US & Canada): 28 orders, over 600 families, ca. 12,500 genera, and >86,000 spp.(1)(2)
Three body parts: head
, and abdomen
typically two pair of wings
; some groups have one pair or none
Usually one pair of compound eyes
; simple eyes (ocelli
) present in many groups
See BugGuide Glossary
See Overview of Orders of Insecta
--an illustrated guide to the orders of insects.
worldwide and throughout North America (NB: aquatic marine forms conspicuously absent)
There are two prominent types of life cycles among the insects:
insects (e.g., dragonflies
, true bugs
) undergo gradual, or incomplete, metamorphosis. Immature stages (usually called nymphs
) go through a series of molts, gradually assuming an adult form. Since the wings develop on the outside of the body, these groups are called exopterygotes
. Some orders have immature stages that are aquatic. These possess specialized structures for aquatic life, such as gills, and are called naiads
, or larvae.
insects have a four-stage life cycle: egg, larva, pupa, and adult (imago). The following orders of insects are holometabolous:
- Antlions, Lacewings and Allies
- Ants, Bees, Wasps and Sawflies
- Butterflies and Moths
- Scorpionflies, Hangingflies and Allies
- Twisted-winged Insects
This group is referred to as Endopterygota
All the winged insects (including those who have lost their wings over the course of history) constitute the large taxon Pterygota
, sometimes treated as a subclass of Insecta.
The sequence of orders of winged insects used in the guide generally follows that used in Arnett (2000)(1)
. Forum discussions about the sequence of insect orders lead to the consensus (see relevant 2006
to use an alphabetical sequence that would place related groups far apart. Please discuss before making changes.
Pterygota orders listed alphabetically
Further order consolidation is to be expected, as Mantoptera will be lumped with Cockroaches & Termites, and Siphonaptera with what is currently called ‘Mecoptera’.
by John R. Meyer (excellent source with systematics, descriptions, images)
Insects of Kansas
by Roy J. Beckmeyer