What's That Bug? does not endorse extermination

Assassin bug
November 13, 2009
I was going to send you a burying beetle, but then this one popped up unexpectedly so here he is. I’ll save the burying beetle for another night.
The cat loves/hates them. Loves to stalk, hates being spit on.
Oroboros
Denver, CO

Western Conifer Seed Bug

Western Conifer Seed Bug

Dear Oroboros, you snake,
This is not an Assassin Bug.  It is a Western Conifer Seed Bug, one of the Leaf Footed Bugs in the family Coreidae.  Just this morning we wrote about the Western Conifer Seed Bug for the Household Intruders chapter of our book, so we are just going to post that section as part of your reply.  We hope our readership enjoys this short preview.

Western Conifer Seed Bug (excerpt from Curious World of Bugs draft)Had it remained confined to its native Pacific Northwest range, the Western Conifer Seed Bug, Leptoglossus occidentalis, would never have made our Rogue’s List of household intruders, but during the 1970s, individuals were noticed in the eastern portions of North America, thousands of miles from their home territory.  These introductions were probably due to human assistance, though the exact source of the accidental establishment cannot be ascertained.  The Western Conifer Seed Bug found the climate in the eastern part of the continent to its liking, and there was a readily available food source, and the species multiplied.  Both adult and immature Western Conifer Seed Bugs feed on the sap of the resin rich green pine cones, and occasionally the twigs and needles of many species of conifers, so they do little damage to the trees themselves, though they do have a negative effect on the developing cones which wither and fall off the tree.  The Western Conifer Seed Bug is now very well established across North America, everywhere but the southern and gulf states.  In the very late twentieth century and into the early twenty first century, reports of sightings in many European countries were confirmed, doubtless due to the importation of stacks of lumber that may have contained hibernating adults.
The Western Conifer Seed Bug can be recognized both by its dull orange and brown coloration and its long antennae.  Its most distinguishing feature though is the widening on the hind leg that gives the family members a shared common name of Leaf Footed Bug or Big Legged Bug.  Since homemakers are often prone to swatting this relatively large intruder should it be encountered inside, this action releases what some to find to be an offensive odor, and what others have described as the scent of apples, the smell of grass, or the odor of pine.  Because of the scent, the Western Conifer Seed Bug is sometimes mistaken for a Stink Bug, though the odor released by a Stink Bug is rarely described as pleasant.
Because of their habit of entering homes to seek shelter from the winter cold, Western Conifer Seed Bugs gain attention in the autumn along with some true Stink Bugs like the Brown Marmorated Stink Bug.  None of these species pose any threat to humans, pets or to the home.  They will not breed indoors and they will not bite.  Since they are just seeking shelter from the elements, if they escape notice upon entering, they will find a secluded place and rest until the warm sunny days of spring arrive.  At that time, they again attract attention as they seek egress at the bright windows.

Update with new photo
How fascinating! I was quite sure of the general identity before I sent that, so I am really glad now for the serendipity that caused me to choose it and learn something new.
I do tend to find them closest to the window that is right next to a pine tree which now makes a lot of sense.
So here’s a followup then. I found this guy in my bathtub, and suspect that they are the same species but perhaps this is a juvenile?
I named the photo replicator because something about it reminded me of the replicators from the Stargate series.

Masked Hunter

Masked Hunter

Your replicator is an Assassin Bug, an immature Masked Hunter.  It may bite, but does not spread Chagas.  Thanks to clickbeetle for pointing out there was a link with a new image.

What's That Bug? does not endorse extermination
Location: Denver, Colorado

4 Responses to Western Conifer Seed Bug: and What’s That Bug? book preview. Follow up Masked Hunter

  1. oroboros says:

    How fascinating! I was quite sure of the general identity before I sent that, so I am really glad now for the serendipity that caused me to choose it and learn something new.

    I do tend to find them closest to the window that is right next to a pine tree which now makes a lot of sense.

    So here’s a followup then. I found this guy in my bathtub, and suspect that they are the same species but perhaps this is a juvenile?

    I named the photo replicator because something about it reminded me of the replicators from the Stargate series.

  2. oroboros says:

    Also, I feel a bit better too with this identification. I’m far enough south that rumors of Chagas disease spreading to the U.S. had me concerned.

  3. clickbeetle says:

    The “replicator” is a masked hunter. It is an immature true bug, but not of the Western Conifer Seed Bug. There are a lot of other pictures of the masked hunter elsewhere on WTB.

  4. oroboros says:

    Thanks for the followup and your help clickbeetle.

    I find both those around often enough that sooner or later I’ll have a dead one. I have a new digital microscope from thinkgeek and have really been anxious to point it at some specimens.

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