Archostemata

Archostemata
Temporal range: Late Permian–Recent
Tenomerga mucida
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Suborder: Archostemata
Kolbe, 1908
Families

Crowsoniellidae
Cupedidae
Jurodidae
Micromalthidae
Ommatidae

The Archostemata are the smallest suborder of beetles, consisting of 50 living species in five families and over 200 described fossil species.[1] 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. Modern archostematan beetles are considered rare, but were more diverse during the Mesozoic.

The term "Archostemata" is used more broadly by some authors to include both modern archostematans as well as stem-group beetles like "protocoleopterans", which some modern archostematans closely resemble to due to their plesiomorphic morphology.[2] Genetic research suggests that modern archostematans are a monophyletic group. Some genetic studies have recovered archostematans as the sister group of Myxophaga.[3]

A 2009 paper argued that the poor diversity of modern Archostemata, compared with the staggering evolutionary success of most other Coleoptera lineages, could be due to the lower efficiency of the thoracic locomotor apparatus, the absence of cryptonephric Malpighian tubules, and competition with other beetles more adapted to angiosperms.[4]

  1. ^ Li, Yan-Da; Tihelka, Erik; Yamamoto, Shûhei; Newton, Alfred F.; Xia, Fang-Yuan; Liu, Ye; Huang, Di-Ying; Cai, Chen-Yang (2023-08-22). "Mesozoic Notocupes revealed as the sister group of Cupedidae (Coleoptera: Archostemata)". Frontiers in Ecology and Evolution. 11. doi:10.3389/fevo.2023.1015627. ISSN 2296-701X.
  2. ^ Boudinot, Brendon Elias; Yan, Evgeny Viktorovich; Prokop, Jakub; Luo, Xiao-Zhu; Beutel, Rolf Georg (28 July 2022). "Permian parallelisms: Reanalysis of †Tshekardocoleidae sheds light on the earliest evolution of the Coleoptera". Systematic Entomology. 48 (1): 69–96. doi:10.1111/syen.12562. ISSN 0307-6970. S2CID 251171914.
  3. ^ Hörnschemeyer, Thomas (July 2009). "The species-level phylogeny of archostematan beetles—where do Micromalthus debilis and Crowsoniella relicta belong?". Systematic Entomology. 34 (3): 533–558. Bibcode:2009SysEn..34..533H. doi:10.1111/j.1365-3113.2009.00476.x. S2CID 84795808.
  4. ^ Friedrich, Frank; Farrell, Brian D.; Beutel, Rolf G. (2009). "The thoracic morphology of Archostemata and the relationships of the extant suborders of Coleoptera (Hexapoda)". Cladistics. 25 (25): 1–37. doi:10.1111/j.1096-0031.2008.00233.x. PMID 34879618. Retrieved 31 July 2024. (Erratum: doi:10.1111/j.1096-0031.2009.00257.x)