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Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Beetles (Coleoptera) » Polyphaga » Series Cucujiformia » Longhorn and Leaf Beetles (Chrysomeloidea) » Longhorn Beetles (Cerambycidae) » Prioninae » Prionini » Prionus » subgenus Prionus (Prionus subgenus Prionus) » California Root Borer (Prionus californicus)

Species Prionus californicus - California Root Borer

Classification · Other Common Names · Synonyms and other taxonomic changes · Size · Identification · Range · Season · Food · Life Cycle · Internet References · Works Cited

Giant beetle flying at dusk - Prionus californicus - male

Prionus californicus? - Prionus californicus - male

California Root Borer? - Prionus californicus

Large Brown Beetle - Prionus californicus - female

Classification

Kingdom Animalia (Animals)

Phylum Arthropoda (Arthropods)

Subphylum Hexapoda (Hexapods)

Class Insecta (Insects)

Order Coleoptera (Beetles)

Suborder Polyphaga

No Taxon (Series Cucujiformia)

Superfamily Chrysomeloidea (Longhorn and Leaf Beetles)

Family Cerambycidae (Longhorn Beetles)

Subfamily Prioninae

Tribe Prionini

Genus Prionus

No Taxon (subgenus Prionus)

Species californicus (California Root Borer)

Other Common Names

The root-feeding larvae are sometimes called the "Giant Root Borer"(1)

Synonyms and other taxonomic changes

Prionus californicus Motschulsky 1845

Size

24-55 mm (1)

Identification

The following is from Evans & Hogue (1)

Adults:

Robust, reddish-brown to almost black;

Three sharp spines on each side of pronotum;

Saw-toothed antennae with 12 segments (scape, pedicel, and 10 flagellomeres...pedicel very short, 1st flagellomere longest, then decreasing in size apically)(1)

Males with antennae distinctly sawlike, more than 2/3 length of body.

Females with more slender antennae, about 1/2 length of body.

Larvae: Up to 80mm long

Range

w. N. Amer.

Season

Adults active summer through early fall; fly at dusk or in the evening.(1)

Food

Larva feed primarily on living deciduous trees (oaks, madrone, cottonwood) and are also recorded from roots of vines, grasses, and decomposing hardwoods and conifers. Will also attack fruit trees growing on light, well-drained soils (e.g. apple, cherry, peach).(1)

Life Cycle

Entire life cycle may require 3 to 5 years.(1)

Internet References

Cerambycidae Catalog

Works Cited

1.	Field Guide to Beetles of California Arthur V. Evans and James N. Hogue. 2006. University of California Press.

Contributed by Phillip Harpootlian on 1 June, 2005 - 1:30pm
Additional contributions by Mike Quinn, Aaron Schusteff
Last updated 4 September, 2013 - 8:14am

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