Rhysodine beetles make their living feeding on slime molds under the bark of decaying trees . They are instantly recognizable from the grooves on their backs and from their distinctly moniliform (bead-like) antennae. The taxonomic placement of these insects is controversial, but genetic evidence suggests they are a highly specialized lineage of Carabidae, the ground beetles.
photo details: Canon MP-E 65mm 1-5x macro lens on a Canon EOS D60
ISO 100, 1/200 sec, f/13, flash diffused through tracing paper