The Archostemata are the smallest
suborder
Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...
of
beetle
Beetles are insects that form the order Coleoptera (), in the superorder Endopterygota. Their front pair of wings are hardened into wing-cases, elytra, distinguishing them from most other insects. The Coleoptera, with about 400,000 describ ...
s, consisting 45 living species in five families. They are an ancient lineage with a number of primitive characteristics.
Antennae may be thread-shaped (filiform) or like a string of beads (moniliform). This suborder also contains the only beetles where both sexes are
paedogenic, ''
Micromalthus debilis
The telephone-pole beetle (''Micromalthus debilis'') is a beetle native to the eastern United States, and the only living representative of the otherwise extinct family Micromalthidae. They have an unusual lifecycle involving asexually reproducin ...
''. Modern archostematan beetles are considered rare, but were more diverse during the
Mesozoic
The Mesozoic Era ( ), also called the Age of Reptiles, the Age of Conifers, and colloquially as the Age of the Dinosaurs is the second-to-last era of Earth's geological history, lasting from about , comprising the Triassic, Jurassic and Cretaceo ...
. The term "Archostemata" is used more broadly by some authors to include both modern archostematans as well as
stem-group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...
beetles like "
protocoleopterans", which some modern archostematans closely resemble to due to their
plesiomorphic
In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all members of a clade, which does not distinguish the clade from other clades.
Plesiomorphy, symplesiomorphy, apomorphy, and ...
morphology. Genetic research suggests that modern archostematans are a
monophyletic
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...
group. Some genetic studies have recovered archostematans as the sister group of
Myxophaga
Myxophaga is the second-smallest suborder of the Coleoptera after Archostemata, consisting of roughly 65 species of small to minute beetles in four families. The members of this suborder are aquatic and semiaquatic, and feed on algae.
Descrip ...
.
Taxonomy
There are five extant families.
* Family
Crowsoniellidae Iablokoff-Khnzorian, 1983
* Family
Cupedidae
The Cupedidae are a small family of beetles, notable for the square pattern of "windows" on their elytra (hard forewings), which give the family their common name of reticulated beetles.
The family consists of about 30 species in 9 genera, with ...
Laporte, 1838
* Family
Micromalthidae Barber, 1913
* Family
Ommatidae
The Ommatidae are a family of beetles in the suborder Archostemata. The Ommatidae are considered the extant beetle family that has most ancestral characteristics. There are only seven extant species, confined to Australia and South America. How ...
Sharp and Muir, 1912
* Family
Jurodidae Ponomarenko, 1985
See also
*
List of subgroups of the order Coleoptera
This article scientific classification, classifies the subgroups of the order Coleoptera (beetles) down to the level of family (biology), families, following the system in "Family-group names in Coleoptera (Insecta)", Bouchard, et al. (2011), with ...
References
External links
Tree of Life - Archostemata
{{DEFAULTSORT:Archostemata
Insect suborders
Extant Permian first appearances
Taxa named by Hermann Julius Kolbe