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Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Beetles (Coleoptera) » Adephaga » Ground Beetles (Carabidae) » Paussinae » Metriini » Metrius

Genus Metrius

Metrius contractus - Metrius contractus Bombardier Beetle - Metrius contractus Beetle - Metrius contractus Metrius contractus Ground beetle - Metrius contractus Big Stinky Beetle - Metrius contractus Belden-J.2021.01 - Metrius contractus contractus? - Metrius contractus
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Coleoptera (Beetles)
Suborder Adephaga
Family Carabidae (Ground Beetles)
Subfamily Paussinae
Tribe Metriini
Genus Metrius
Explanation of Names
Metrius Eschscholtz 1829
Numbers
2 spp., both in our area(1)
Size
9‒13.5 mm(2)
Identification
Black, convex beetles found from California to British Columbia, as well as Idaho.
Both spurs of front tibia apical (as opposed to one being preapical)
Head with one setigerous puncture over each eye.
Hind coxae not contiguous.
Middle coxal cavities disjunct.
Anterior coxal cavities closed.
Range
w NA (BC to CA & MT)(1)
Remarks
Secretes defensive chemicals (quinone-based and hot, like bombardier beetles) as a frothy mixture that can either be held at the rear of the body or channeled forwards along special tracts. This is perhaps a primitive state among beetles with similar defensive chemicals. See (3)
Works Cited
1.Catalogue of Geadephaga (Coleoptera, Adephaga) of America, north of Mexico
Bousquet Y. 2012. ZooKeys 245: 1–1722.
2.The ground-beetles (Carabidae, excl. Cicindelinae) of Canada and Alaska, parts 1—6
C.H. Lindroth. 1961. Opuscula Entomologica Supplementa XX, XXIV, XXIX, XXXIII, XXXIV, XXXV.
3.Spray mechanism of the most primitive bombardier beetle (Metrius contractus).
Eisner, T., et al. . 2000. Journal of Experimental Biology 203, 1265-1275.
Contributed by Phillip Harpootlian on 17 November, 2006 - 9:21pm
Additional contributions by Bbarnd, v belov
Last updated 28 September, 2023 - 5:21pm

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