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Species Prionus californicus - California Root Borer

Prionus heroicus - Prionus californicus Root Borer, Prionus? - Prionus californicus please tell me its NOT a cockroach - Prionus californicus Prionus sp. - Prionus californicus Long horned giant wood borer? - Prionus californicus - female Prionus californicus - female #271 - Prionus californicus Prionus californicus
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
24-55 mm (1)
The following is from Evans & Hogue (1)

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
w. N. Amer.
Adults active summer through early fall; fly at dusk or in the evening.(1)
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
Works Cited
1.Field Guide to Beetles of California
Arthur V. Evans and James N. Hogue. 2006. University of California Press.