Additional image showing details of setae on elytra, as that seems to be important in the one key I found online:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6019436/
– Declivital interstriae 1 armed by one or two small denticles at base, interstriae 3 with one prominent tubercle near middle of declivity (minor denticles may also be present); declivity flat to subsulcate, interstriae 2 not impressed, strial punctures distinct-->9
9--Discal interstrial setae regularly spaced, numerous; larger, more robust species; color dark reddish brown; 2.8–3.2 mm.-->bispinatus Eichhoff
– Discal interstrial setae sparse or absent; smaller, more slender species; color light orange to reddish brown; 2.4–2.9 mm.-->ferrugineus (Fabricius)