Dicondylia

Dicondylia
Temporal range: Early Devonian (but see text)–Present
Diversity of dicondylians from different orders.
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Hexapoda
Class: Insecta
(unranked): Dicondylia
Hennig, 1953
Subgroups

Dicondylia is a taxonomic group (taxon) that includes all insects except the jumping bristletails (Archaeognatha). Dicondylia species have a mandible attached with two hinges to the head capsule (dicondyl), in contrast to a hypothetical ancestral mandible with a single ball joint (monocondyl); the members of Archaeognatha do in fact have dicondylic mandibles, though they are not identical to the structure seen in "true" dicondylic insects.