The Bug Geek

Insects. Doing Science. Other awesome, geeky stuff.

Tag Archives: Coleoptera

Hey Geek, what’s this? Mystery critter from northern Ontario

This latest installment of “What’s This?” comes via email from my own aunt Elizabeth, who discovered a new-to-her insect while at her cottage, which is on a small bay north of Manitoulin Island in Ontario. She has been cottaging on the same body of water since she was a child, and knows the wildlife pretty well, but:

Never saw this before. Any ideas?

Photo by Elizabeth, used with permission.

I’ll bet that many of you recognize this charismatic beastie…

It’s the unmistakable American Burying Beetle, Necrophila americana (Silphidae). The only species of the genus in North America, it is incredibly widespread in the eastern and central areas of the continent. As the genus name implies, it is a lover of dead things: a carrion-feeder, that also feeds on maggots and other carrion beetles.

Although their diet may seem distasteful, they perform a critical service as part of nature’s clean-up crew. A few years ago, in my garden, I watched a pair of carrion beetles (a different species than this one) drag a mouse carcass into a patch of loose soil, then, over the course of an hour or so, they buried the entire thing until no trace remained. This seemed to be an amazing feat for two insects a fraction of the size of the rodent! The young of that pair of beetles would have fed on the carcass after they hatched: burying beetles are excellent providers in addition to being marvelous cleaner-uppers…

Photo Friday – uncooperative but adorable Tenebrionid beetle (Neatus tenebrioides)

We heat our house primarily with our wood stove in the winter. Right now we’re in the middle of the difficult transitional period where it’s not cold enough to have a good, ripping fire going 24-7, but too cold to let the fire go out. It’s a delicate balancing act, I tell ya.

Anyways, this all requires some extra chores, namely, the hauling and stacking of logs. Earlier this week I was moving logs from our wood shed into the alcove at the front of our house (it’s much nicer to get wood from the alcove whilst in jammies on a chilly morning), when I found a little fellow who’d been all tucked up in a little nook of bark, ready to wait out the winter.

I was tremendously rude and brought him inside and asked him to pose for a picture or twenty.

He was not very obliging about sitting in my white box, and was quite determined to escape post-haste. This all made for lots of blurry and badly-framed and over/under-exposed photos and an exasperated photographer.

I even tried the TOTALLY CHEATING method of cooling him down with an ice pack…but the moment he warmed up…zoom, off he’d run!

Finally, I decided to try providing him with a more “normal” substrate: some bark and a leaf scavenged from the alcove. On the leaf he went…and you could practically hear the “Aaaaaahhhh, this is more like it!

teneb on leaf small

He settled down almost immediately.

Then, after discovering the wood chip, he became uncooperative again (he wanted only to be UNDER the chip, not on it), but stopped roaming long enough to peek at me for a final (rather adorable) picture:

Tenebrionid (rather adorable)


(Totally cute darkling beetle: Neatus tenebrioides (Tenebrionidae)

“A most variable species,”…

…writes Lindroth (1969) of Pterostichus (Stereocerus) haematopus in his 1200+ page taxonomic key of Canadian/Alaskan ground beetles.

“Black…upper surface as a rule with metallic lustre (bluish, green, brass or coppery)…”

Pterostichus (Stereocerus) haematopus - black/metallic version - dorsal

Black with greeny-metallic lustre – check.

But, lo:

“…elytra sometimes rufinistic [reddish]”.

Well that’s quite different, isn’t it?

Pterostichus (Stereocerus) haematopus - rufinistic version - dorsal

Ok, reddish – check.

These two again from the side:

Pterostichus (Stereocerus) haematopus - black/metallic version - lateral

Pterostichus (Stereocerus) haematopus - rufinistic version - lateral

Believe it or not, these two beetles are the same species. This is a great example of why a well-assembled taxonomic key is critically important to making accurate identifications. I had rough-sorted (i.e., “guesstimated/eyeballed”) these beetles into different groups initially, but the reddish-brownish one (of which there are few) just kept keying out the same as the more prevalent metallic version. I checked in with the experts at the Canadian National Collection to make sure I hadn’t goofed – and I hadn’t.

The key I’m using for my ground beetles was written by Charles H. Lindroth over the course of about eight years, and represents the sum of several “smaller” publications. It is truly a magnum opus in the world of beetles (indeed, of entomology) and is still considered the ultimate reference for this family, even after 35+ years of new research and updated phylogenetic/taxonomic work.

(For Morgan: Taxonomy FTW!)


Lindroth, C.H., 1961-1969. The ground-beetles (Carabidae, excl. Cicindelinae) of Canada and Alaska. Opusc. Entomol. Suppl. 20,1-200; 24,201-408; 29,409-648; 33, 649-944; 34, 945-1192; 35, I-XLVIII.

Mind-controlling beetle parasite

This post was chosen as an Editor's Selection for

I’m sorting through beetle specimens collected from Iqaluit, Nunavut today.

There’s not a ton of diversity in the samples so far, and I was starting to get a little bored, until I saw this:


Say it with me now: “EWWWWWWWWWW“.

Now say, “COOL!”

Very good.

This poor ground beetle (family Carabidae) has been parasitized by a nematode-like worm called a hairworm, or “Gordian worm”, (Gordiaceae: Nematomorpha).  Adult hairworms are free-swimming, water-dwelling animals (either in fresh or salt water). They mate and produce young (larvae) in the water.  The larvae require two hosts. First they infest various small arthropods (called paratenic hosts), like mosquito larvae. Next, those small paratenic hosts are consumed by other, larger arthropods – ground beetles fit the bill since they are heavy-bodied, voracious predators.  Worldwide, at least 70 species of ground beetles are known to be hosts for hairworms.

When the worm is mature, it has to leave its host and return to the water to reproduce. If it has infested an aquatic insect, it has no trouble making its way back to the water. However, if it has chosen a terrestrial insect as a host, things get a little more complicated.

Like so many parasites, the hairworm can use a type of mind-control to affect the behaviour of its host. In this case, it compels the terrestrial beetle to seek out water, then drown itself. Yikes! For this beetle, which I caught in a yellow pan trap, I can envision one of two scenarios: 1) the worm was mature, and convinced the beetle to take a dip in the preservative fluid in the trap, or 2) the beetle just happened to wander into the trap, and the worm decided to abandon ship. Whatever happened, it was not a happy “ending” for either animal!


Not a happy ending.

Poinar G Jr, Rykken J, & LaBonte J (2004). Parachordodes tegonotus n. sp. (Gordioidea: Nematomorpha), a hairworm parasite of ground beetles (Carabidae: Coleoptera), with a summary of gordiid parasites of carabids. Systematic parasitology, 58 (2), 139-48 PMID: 15449829

I selected this post to be featured on my blog’s page at Nature Blogs.

Photo Friday – Asian Lady Beetle (Harmonia axyridis)

I’ve ranted about unwelcome insects invading our home before.  The springtime culprits are cluster flies.  This time of year, it’s exotic Asian Lady Beetles, Harmonia axyridis (Coleoptera: Coccinellidae). They were introduced to North America in the 1970’s to control aphid populations and are now one of the most widespread lady beetle species in Canada, due to their winter-hardiness and reproductive rate. 

They make nuisances of themselves at light sources (*bonk* *whap* bonk*), poop on the walls, AND they bite. No seriously, they bite. The cats will chase but not eat them, because they’re reflex bleeders that exude stinky, foul-tasting hemolymph as a form of chemical defense.

I guess they’re sort of pretty though. Sigh.

Asian lady beetle

Harmonia axyridis, the Asian Lady Beetle

One other (kinda neat) thing about this species is the enormous variability is displays in terms of colour, pattern and shape. This individual, for example, is one of the smaller, and redder specimens I’ve ever come across. The number and size of spots can vary, the dominant color can range from black to red…it’s a tough one to ID sometimes!

However, the prothorax (between the head and the wings) holds the most reliable clue. If you look at the black pattern (which is surrounded by large white areas on either side) you’ll note that it forms the shape of the letter “W”, or “M”, if you’re looking at it the other way. This character is pretty consistent regardless of what the rest of the body is doing, color-wise!

%d bloggers like this: