The Bug Geek

Insects. Doing Science. Other awesome, geeky stuff.

Tag Archives: Cerambycidae

Dear March: thank you for the larvae

Dear Month of March,
you are lovely and splendiferous in every way this year; you bathe me in warm sunshine, rouse wildlife from winter slumber, and whisper delicious promises of spring.  
Now, I know that generally you like to blast eastern Ontario with one last big dump of snow.  A big dump of snow that makes us Ontarians pull our boots back out of storage, search our trunks for the windshield scraper, and curse the fact that we decided to get the summer tires put back on.   I understand that you think this is a wonderfully funny joke to play.  I get it.
But if you could NOT this year, I would really, really appreciate it.  It’s too freaking nice out.
Yours Truly,
The Geek
P.S. Thank you for all the cool larvae and excellent ambient lighting today.
I found oodles of goodies today; I am happily satiated with enough photographs to last me to the weekend.  First, I’ll share that I got some excellent pics some Flat Bark Beetle larvae, which really show off the rear-end armaments.  I added them to my old post…check them out (just scroll down a bit)!
Now, for this guy: I think this small long-horned beetle larva is a member of the flat-faced subfamily (Lamiinae).  It has freckles on its head, hee.

Cerambycid (long-horned beetle) larva

The tree I found it on was really, really dead.  The bark practically crumbled away in my hands.  If I had to take a stab at what species the tree was, I would guess white elm.   Anyone have any guesses who this might be? 

I have a question for Ted now.  (Yes, you, Ted.)   Oh heck, I’ll throw this one right out there in case someone else knows too.  

Is there any way to rear critters like these with only the bark that they were tunnelling in, or it is necessary to have a whole chunk of tree?

Winter Treasure Hunt (Part 4: beetles?????)

(Continued from Part 3: the fungus amungus!)     

I promised “beetles” for today’s final installment of my treasure hunt series.  I have some bad news and some good news.       

The bad news: the day I went walkabout on the lonely road, the temperature was well below zero, the snow cover was ample and Wiarton Willie  was a few days shy of dropping the “6 more weeks of winter” bomb; active beetles were in pretty short supply.       

The GOOD news:  in keeping with the theme of  “tracking” from Parts 1 and 2 , I still found ample trace material to satisfy my Coleopteran cravings.      

An important part of any forest ecosystem is its wood-boring beetles.  There are many families of beetles that use trees (living or dead) as a food source, including the longhorned beetles (Cerambycidae), metallic wood-boring beetles (Buprestidae), as well as several snout beetle (Curculionidae) sub-families: bark and ambrosia beetles (Scolytinae) pinhole bark borers (Platypodinae).        

The larvae of these insects feed beneath the bark, happily chewing tunnels (or “galleries”) through the tissues responsible for moving water and nutrients throughout the tree.  A heavy load of wood-boring larvae can kill a tree by effectively cutting off its circulation (called “girdling”, picture below).   Boring beetles can also carry fungi, viruses and other pathogens into the tree, exacerbating the injury.      

Girdled tree - damage is extensive enough to kill. Several types of wood-borers have been feeding at this site.

 Signs of wood-borer activity can be seen on trees year-round.  These include scars left on the bark from ovipositing (egg-laying) females, exit holes from newly-formed emerging adults, and larval galleries.   The frass (wood-shaving-esque poop) of some larvae can be found in the forks of branches or at the base of a tree, although many species simply pack their galleries with excrement (below).  Locating these signs on dead or dying trees is a fairly simple task, as the bark often sloughs off or cracks and exposes the beetle damage beneath.        

Serpentine (S-shaped) larval galleries (typical of Buprestids), packed with frass.

Round exit hole (typical of Cerambycids) - note jagged edges created by chewing action of emerging adult beetle

D-shaped exit hole (typical of some Buprestids) from same tree. I observed woodpecker damage from a considerable distance; these exit holes are ~4mm in diameter and required a closeup inspection, but the woodpecker activity was a good first hint at their presence.

Bark beetle (Scolytinae) galleries-a female beetle deposits multiple eggs along the central chamber. Each "branch" stemming from it is formed by an individual larva.

Wood-boring beetles generally attack weak or dying trees.  That said, some species do feed on healthy trees; these  include serious forest pests such as the introduced Emerald Ash Borer (Agrilus planipennis) and Asian Long-horned Beetle (Anoplophora glabripennis), both of which are found in Ontario.  Living trees with thick, rough bark often hide signs of their injuries for several years until the damage is extensive.  This can make detection particularly challenging for monitoring programs.  In younger trees, or species with smooth bark, it can be easier to detect recent borer damage.       

For example, (TEXT OF SHAME removed and tossed away in SHAME).  (Link to PHOTO OF SHAME here.)  New, random pic of multiple galleries, exit holes, etc. created by ACTUAL beetles inserted in its place:   

Sub-in for PHOTO OF SHAME: real beetle damage.

Wood-boring beetle larvae are an important food source for many animals, including other insects (such as parasitic wasps) and birds, especially woodpeckers.  Woodpecker feeding damage can actually be an early indication of a beetle infestation in an otherwise healthy-looking tree, and is therefore often used in forest pest surveys.        

Pileated woodpecker damage

Pileated Woodpecker damage. Note small beetle exit holes on exposed trunk below.

 The large gouges and piles of wood chips left by the enthusiastic boring of the Pileated Woodpecker (above) are unmistakable.  However, the tidier drill-holes of some smaller woodpeckers, such as the Yellow-bellied Sapsucker,  can easily be confused for beetle entry or exit holes (below).  The woodpecker damage can be recognized by the neat, evenly spaced rows of holes; beetles are not quite so organized.       

Yellow-bellied sapsucker feeding damage

Yellow-bellied sapsucker damage.

If you made it this far, thanks!  I think I’ll be visiting the lonely road again in the near future to see what other goodies I can find.  I’ve also decided to make more time to take advantage of the wild spaces near my home.  I promise to share!     


White Pine Insect Fauna Reference (no longer relevant due to SHAME, but still interesting):      

Saunders, W.M. 1883. Insects injurious to the White Pine.  Annual Report of the Entomological Society of Ontario. pp 52-59.      

First attempt with new macro lens

Let it be stated for the record that I have a point-and-shoot camera, a Canon PowerShotSX10.  This is a fully serviceable little machine, with lots of bells and whistles and settings etc.  But I can’t interchange lenses, nor can I focus manually.  These present challenges when I want to photograph the very tiny or the very far away. 

My beloved DID manage to find me an add-on macro lens, however, that was compatible with my Canon: a raynox super macro conversion lens (DCR-250).  It comes with an adaptor that allows me to clip the macro over my existing lens with a simple spring mechanism.  

I was fiddling with the lens today for the first time.  I was using only the ambient light (a grey winter day, indoors) – I really need to get a flash – and was aided by an Optex T120 Minipro Tripod; it’s about 8 inches high. 

My subjects: some of my latest additions to my collection; a bunch of critters I found, forgotten, in the back of the freezer.  Some were 3 years old.  They sat in a relaxing jar for several days and I’m quite pleased at how flexible I was able to get them.  They’re not as perfectly posed as I usually like, but considering how long they’d been on ice, I’ll take what I can get.  So here you go; please do tell me if I’ve identified anything incorrectly!

Saperda imitans (Cerambycidae) (Thanks to Ted MacRae for the ID correction, and letting me know I’ve got a goodie here! I had falsely identified it as Saperda tridentata.)

Megacylene robinae (Cerambycidae)

Dorcus parallelus (Lucanidae)

Arrhenodes minutus (Brentidae)

Calligrapha californica (Chrysomelidae)

Cicindela tranquebaria (Cicindelidae)

%d bloggers like this: