Archostemata

Definition

A suborder of Coleoptera (beetles) comprising approximately 50 extant species in five families—Cupedidae, Ommatidae, Micromalthidae, Crowsoniellidae, and Jurodidae—plus over 200 described fossil species. Members retain numerous plesiomorphic traits, including filiform or moniliform antennae and, in Micromalthus debilis, the unique condition of paedogenesis in both sexes. The group represents an ancient lineage that was more diverse during the Mesozoic; modern archostematans are relictual and geographically restricted.

Etymology

New Latin, from Greek archos (chief, primitive) + stemma (wreath, crown), referring to the suborder's basal position among beetles.

Example

The telephone-pole beetle Micromalthus debilis (Micromalthidae) is the only archostematan known to exhibit paedogenesis in males and females, with larvae capable of producing further larvae parthenogenetically.

Related Terms

• Coleoptera
• Adephaga
• Polyphaga
• Myxophaga
• Paedogenesis
• plesiomorphic
• Cupedidae
• Ommatidae

Usage Notes

Archostemata is one of four living suborders of Coleoptera, alongside Adephaga, Polyphaga, and Myxophaga. It is consistently treated as the sister group to all other beetles, though some phylogenetic analyses debate internal relationships. The suborder is not monophyletic in some fossil-only classifications; extant archostematans are sometimes called 'reticulated beetles' in reference to the net-veined elytra of Cupedidae. The term is capitalized as a formal taxon name.