Synonyms and other taxonomic changes
Has also been called: P. origonensis, P. coerulescens, P. chalybaeus
Identification
According to Benesh 1946:
Non-dentate mandible
Longitudinal pronotal depression
Head and pronotum black
Sides sinuate at basal angles (obtuse)
Head widest behind eyes
Anterior margin of pronotum sinuate
As well as some further marks, but the key uses the first four to differentiate from P. delicatulus
Life Cycle
Larvae have been found in rotting logs of maple, madrone, live oak, blue gum, and red alder
Remarks
The non-denticulate mandibles separate the oregonensis group. The other species in this group is Platycerus delicatulus Which is found in Japan, so the likelihood of you encountering it is rather slim
Print References
Benesh, B. A systematic revision of the Holarctic genus Platycerus Geoffroy (Coleoptera: Lucanidae). Transactions of the American Entomological Society. 1946. 63:139-203