#10,000: Mystery Beetle from Hawaii may be Callirhipis cardwellensis

What is this?
May 13, 2010
I live in Hawaii on Oahu in the damp part of Kaneohe, and in my hall way was this creature on the wall. My brother touched it and it fell off easily. He picked it up and the bushy antennae moved around like satellites.
Curious and can’t find the name anywhere
Oahu, Hawaii

Dear Curious,
First, we want to congratulate you on being our 10,000th posting, though we believe that count may be off since we are still finding that some postings vanished when we made our major site migration in September 2008.  At any rate, our web posting program, WordPress, indicates that you are #10,000.  Second, we want to apologize to Amy who because of a counting error on our part, was informed that her Giant Eastern Crane Fly was the 10,000th posting, and we had to yank the distinction away when we realized we had dropped a number.  None of that has anything to do with your question, which alas, for the moment, will remain unanswered.
This is surely a beetle, but we are unable to distinguish any telltale features but for those gloriously pectinate (or are they plumose?) antennae, .  Certain Click Beetles in the family Elateridae have pectinate antennae, and many Glowworm Beetles have pectinate antennae.  Even some Fireflies have pectinate antennae.  Each of these is a possibility, and BugGuide has numerous mainland North American species of each categorized together in the superfamily Elateroidea.  Alas, the Insects of Hawaii website indicates a curious dearth of these families represented in Hawaii.  We personally find it quite hard to believe that there are no Glowworms or Fireflies in Hawaii.  Our first thought upon viewing your image, and often that first impression, formulated before logic steps in to discount it has proven to be correct, was that your beetle has the outline of a Metallic Wood Boring Beetle in the family Buprestidae, but we knew of no examples of Buprestidae with such exaggeratedly pectinate antennae.  Taking a chance on that hunch, we found an article in the Journal of the Kansas Entomological Society, vol 39, no. 2, which is posted online, that indicates “Male Xenorhipis brendeli LeC. possess elaborate pectinate antennae which presumably are the sensory organs involved in locating virgin females of the same species.”  While it looks nothing like your specimen according to the photos on BugGuide, it does open up the possibility that your beetle might be a Buprestid.  Though we have drawn a blank on your identification, we hope one of our readers might have a clue as to the identity of this distinctively shaped beetle.

May 14, 2010
Looks an awful lot like a callirhipid. See picture at:
mct5548