Currently viewing the category: "Fungus Beetles and Pleasing Fungus Beetles"
What's That Bug? does not endorse extermination

Subject: Oak Tree Beetle
Location: Foothills east of Sacramento, Ca
August 1, 2016 7:11 am
I live in Northern California in the Sierra foothills. We recently had a large, established oak tree die. I noticed a couple nodes at the base that I was able to break off. I found an infestation of black and orange beetles. Trying to figure what they are, if they killed the tree or if they just move in after the tree is dead/dying. And what to do to make sure they don’t spread to our other trees.
Signature: Thank you, Ian

Pleasing Fungus Beetles

Pleasing Fungus Beetles

Dear Ian,
These are Pleasing Fungus Beetles, probably
Megalodacne fasciata, and they are not responsible for the death of your oak tree, however, their presence is tied to the health of the tree.  According to BugGuide:  “larvae and adults feed on the fruiting bodies of fungi growing in decaying wood.”  So, as the tree began to die, it was invaded by the fungus and the fungus attracted the Pleasing Fungus Beetles.

What's That Bug? does not endorse extermination

Subject: Classy black beetle with orange dot. Not a lady bug.
Location: Troy, VA
July 30, 2016 12:45 pm
I saw this beetle last night and I think he is terribly elegant. I’m very curious as to what it is, I can’t find beetles like it with one orange dot. He does, alas, seem to be missing at least one leg.
thank you
Signature: Grace Pedalino

Polyphore Fungus Beetle:  Penthe obliquata

Polyphore Fungus Beetle: Penthe obliquata

Dear Grace,
This is a Polyphore Fungus Beetle in the family Tetratomidae,
Penthe obliquata, and we identified it in Arthur E. Evans wonderful book “Beetles of Eastern North America”.

What's That Bug? does not endorse extermination

Subject: Cockroach or beetle?
Location: Columbus, OH
July 21, 2016 4:19 am
Found this guy stuck on its back in my kitchen. I live in an old home (1920) in an urban neighborhood. I helped him out and got him on his feet but would like to know what exactly I helped. Is it a cockroach or a beetle?
Signature: Apprehensive helper

Pleasing Fungus Beetle

Pleasing Fungus Beetle

Dear Apprehensive helper,
This is a Pleasing Fungus Beetle in the genus
Megalodacne which we identified on BugGuide where it states:  “Larvae feed on bracket fungi. Adults overwinter under bark, often in groups.”  Perhaps there is a large tree with mushrooms growing on it near your kitchen and this individual accidentally found its way indoors.

What's That Bug? does not endorse extermination

Subject: Beautiful Beetle
Location: Cheyenne cannon, Colorado Springs , Co
June 14, 2016 10:10 am
Hi Mr. BugMan,
I found this wonderfully beautiful beetle out on a nature hike with my children. Let me rephrase we found about 50 of them on a pine log. I would love to know what specimen it is and if it is native to Colorado .
Signature: Stephanie Clements

Pleasing Fungus Beetle

Pleasing Fungus Beetle

Dear Stephanie,
This Pleasing Fungus Beetle was likely emerging from the log after feeding  on fungus growing on the pine log as larvae.  According to The Firefly Forest:  “Pleasing Fungus Beetles (
Gibbifer californicus) are blue, fungus-loving beetles found in parts of Wyoming, Colorado, Kansas, New Mexico, Arizona, and Mexico. Here in Arizona, they are fairly common in moist riparian woodlands with large trees. Adult Pleasing Fungus Beetles emerge in the summertime and are most numerous during the summer monsoon rains.”  According to BugGuide:  “Adults feed on nectar, pollen, and some fungi. Larvae feed on wood-destroying fungi.”

What's That Bug? does not endorse extermination

Subject: Help Identify
Location: Colorado
April 28, 2016 1:56 pm
found these on a few mature Douglas fir.
Signature: John

Unknown Exuviae

Probably Pleasing Fungus Beetle Exuviae

Dear John,
These are the exuviae or shed exoskeletons of some unknown insect.  We will continue to research their identity.

Unknown Exuviae

Probably Pleasing Fungus Beetle Exuviae

Unknown Exuviae

Probably Pleasing Fungus Beetle Exuviae

Update May 4, 2016:  Introducing our new intern Bennett
Several weeks ago, we received an intriguing request from a local neighbor that eventually led to a meeting with our neighbor and his young science-minded son.  In his free time, Bennet will be attempting to identify the currently 444 unidentified postings in our archives.

Subject: Need Help?
Location: Los Angeles
April 27, 2016 9:33 pm
Hi Daniel,
I am a neighbor on Mt. Washington (Ave 37) and I have a science minded teenager. He’s done experiments at the Cabrillo Aquarium, won multiple medals in the LAUSD science bowl since grade 5 and was Captain of the Eagle Rock Science Olympiad team that went to the national finals in 2013. I was wondering if you ever need help or took on an intern (non-paid of course) for WtB? He wants to study entomology and I thought perhaps a project like yours would be a fun spot for him.
Thanks,
Todd

Here is Bennett’s first attempt at identifying a recent posting.

May 3, 2016
Hi Daniel, this is Bennett. I’m sorry for not looking into the unidentified post earlier, I had a lot of schoolwork getting in the way. Now that I spent some time looking at it and doing some research it seems to resemble some sort of carpet beetle larvae shedding. I’m not able to give a definite ID on species, and I could be wrong on this, but after doing some research it’s my best guess so far. I’ve attached 2 images that seem similar to the images the person provided, but the main difference is the lack of spikes at the tip of the tail. I hope this helps in some way.

Thanks so much for looking into this unidentified posting Bennet.  Our big doubt regarding Carpet Beetle exuviae is that the habitat seems wrong.  The exuviae are hanging from the tip of the abdomen, which is a common orientation for Lepidoptera pupae as well as Coleoptera pupae.  Our initial thought is that this was most likely one of those two orders.  We do have one request in the future:  Please provide links to images you locate in your online research rather than to attach the images.  We cannot pilfer images from another site to post them to WTB? as that would be plagiarism.  A better strategy is to link either to an outside site or even better, to link to our own archives.  We are not yet closing the book on this ID.  Searching for caterpillars or beetle larvae that feed in large numbers on Douglas Fir would be a good start.  We would also not entirely rule out that these might be Sawfly exuviae.  We believe they are pupal casings and not larval casings, indicating that the insect that left them has complete metamorphosis.

Update from Bennett:  May 23, 2016
Hi Daniel,
… I do think that I have positively identified the mystery exuviae. The images seem also identical to the exuviae of the Fungus Beetle (Gibbifer californicus), I am almost positive that it is this or another closely related species. Here is the bugguide page that contains the image that I found identical: http://bugguide.net/node/view/253897/bgimage
I hope this is accurate!

Wow Bennett,
That BugGuide posting looks like a really good visual match.  Additionally, according to BugGuide, the species is found in Colorado.  BugGuide also states “Larvae feed on wood-destroying fungi” and “female lays eggs in bark crevices of fallen rotting logs” and though the exuviae are on a branch attached to a tree, it is also possible that it could be a lower, dead branch that has fungal growth.  Of the family Erotylidae, the Pleasing Fungus Beetles, BugGuide notes:  “
larvae and adults feed on the fruiting bodies of fungi growing in decaying wood” and fungus is frequently found on living trees that are compromised.  We agree that though this might not be the exact species, it is likely something closely related.  Great job Bennett.  Thanks so much for helping us to clear up some postings that are currently Unidentified on our site one posting at a time.

What's That Bug? does not endorse extermination

Subject: Beetle ID – Black with green patches
Location: Cuc Phuong National Park, Vietnam
April 9, 2016 12:12 am
Hi there,
I enjoy your site, and it has been a great help to ID some of the local bugs I find in California. Recently I went to Vietnam and this bug caught my attention. I have tried to do my due diligence identifying it myself but I’m not getting anywhere. It was seen March 8th at approximately 8 p.m. For size reference, I think about 3/4″? Any help would be appreciated.
Thank you!
Signature: Alison

Pleasing Fungus Beetle, we believe

Pleasing Fungus Beetle, we believe

Dear Alison,
Based on the shape of the antennae and other features, we believe this is a Pleasing Fungus Beetle in the family Erotylidae, but we have not had any success finding any matching images online with this striking black and green coloration.  The closest we would find is this image on Alex Hyde Photography of an unidentified Malaysian species with similar, though yellow markings.  There are examples of beetles, like the Australian Fiddler Beetle, that have green coloration while other members of the same species are yellow.  There is another similar looking Pleasing Fungus Beetle on the Beetles of Borneo site.  Perhaps one of our readers will have better luck than we have had. 

What's That Bug? does not endorse extermination