Need ID
Location: Cornville, AZ
May 6, 2012 11:19 am
Found on an Arizona Cypress and an Italian Cypress, need an ID.
Thanks –
Signature: Lou

Possibly Cypress Sawfly Larva

Hi Lou,
Though it looks like a caterpillar, this is actually the larva of a Sawfly.  Sawflies are related to bees and wasps, but they do not sting.  When larvae are plentiful, they can defoliate trees and introduced species of Sawflies can be especially problematic.  We did find a matching photo on BugGuide by searching key words like “cypress” and “Arizona” however, the individual is only identified to the family level Tenthredinidae.  We found a reference, but no image, on the Pests of Landscape Trees and Shrubs:  An integrated pest management guide by Steve H. Dreistadt online, and it states:  “Cypress Sawfly
Susana cupressi  About one-half dozen Susana species sawflies feed on broad-needled conifers in the western United States.  The most important species in California, primarily in the south, is the cypress sawfly.  Cypress sawfly primarily damages cypress, but reportedly also feeds on arborvitae and juniper.  Adult wasps are black and yellow.  Larvae are grayish green with rows of whitish dots.  The cypress sawfly spends the winter in a cocoon in the soil and has one generation per year.”  Though the description does not mention a red head, the gray green color and white spots seems to fit.  We are unable to locate a photo to verify this online. 

Hi Daniel –
Thanks for the speedy reply, info is appreciated.
Will do some additional research based on what you said and will
forward any new info that I find to you.
Many thanks –
One more pic attached, about 1/2′ long, this is a dead one.
Lou

Probably Cypress Sawfly

Hi Daniel –
Took a few more shots, confirmed your ID again.
See attached, note the 6 pairs of Prolegs that do not have ‘hooks’ on them as described here –
6 pairs of Prolegs without hooks clearly visible –
Prolegs: The prolegs are stumpy legs that let the caterpillar climb very well, even up vertical surfaces. Caterpillars usually have five pairs of stumpy prolegs on the abdomen. These prolegs have crochets (small grasping hooks) on them. The last pair of prolegs are called anal prolegs; they are at the very end of a caterpillar’s abdomen (hind region). These prolegs disappear in the adult.
Also note that mine has two eyes caterpillars have 6 simple eyes usually as noted here –
Caterpillars have six pairs of simple eyes (ocelli). Ocelli (also called stemmata) are small, simple eyes that can detect changes in light intensity, but cannot form an image. Ocelli are composed of photoreceptors (light-sensitive cells) and pigments. Ocelli are usually located in two clusters of six eyes on the sides of a larva’s head.
More info here –
Sawfly Larva or Caterpillar?
How to Tell the Difference Between Sawfly Larvae and Caterpillars
By Debbie Hadley, About.com Guide

Probably Cypress Sawfly

Thanks for all the additional information Lou.

Found a web site with lots of info, here is a link to a Sawfly Larva pic like the
one we found here.
http://www.ipmimages.org/browse/detail.cfm?imgnum=2121084
Lou

Hi again Lou,
In our opinion, the link you provided to the conifer sawfly
Gilpinia frutetorum (Fabricius) is not the species you submitted in your photos.  The host plant is listed as red pine, not cypress.

Update:  May 12, 2012
Hi Daniel –
Found a few more here, pics attached, munching away on an Italian Cypress.
Web searches indicate that it’s a Susana Cupressi, a Cypress Sawfly.  Not much in the way
of images available for ID, hope the ones I send make it easier for someone else to
ID these guys.
We also have five or more species of Pine Sawflies in the area, some look very similar.
They had been absent in the area for many years and started showing up again a few years ago.
BT will not kill them but many insecticides like Sevin will.  Most times the infestation is not wide
spread enough for concern, but one must be watchful.
Luckily we have only found a few as we have 13 Italian Cypress, some Arizona Cypress, and
6 recently planted Spartan Juniper.  Will keep an eye on all of them.
Thanks for your assistance.
Lou Nigro

Hi Lou,
We appreciate the photos that you attached and they will be a great help to our readers.  Of especial significance is that they support our initial tentative identification, but we were unable to locate any images to support that identification.  We do not post photos taken from other websites, and we cannot locate the websites where you found those photos.  Can you please send a link?  We will then post the link.

Hi Daniel –
Think I confused you.  The three pics I sent were shot here this morning.
I found one image of a Susana Cupressi on the Web, I find references to it,
but only one image here –
http://bugguide.net/node/view/393948/bgimage
An exact match to mine found in a county South of here.  They thought is was a caterpillar and did
not identify it as a Sawfly.
There are lots of images of other types of Sawflies, one attached is a Black Headed Pine Sawfly.
Not the same species as mine but almost an exact match except for the head color.  Found at
http://www.ipmimages.org/search/action.cfm?q=sawfly
Lots of confusion on this one, not very well known.  Our local bug expert at the garden center
said he has not seen one around here for years, he was quite surprised to see the live one we
brought him.
Lou

Cypress Sawfly

Great.  If they are your photos, we will post them.

Cypress Sawfly

Location: Arizona

5 Responses to Sawfly Larva, possibly Cypress Sawfly

  1. Leonardo Malagon says:

    Dear Lou,

    Hi, I have just found this picture online. I am studying a group of sawflies for my PhD here in Europe. I was wondering if either you did collect any of these specimens, or if you could share to me the exact locality and collecting information. I am very interested in these specimens. Please let me know.

    Thanks a lot,
    Leonardo

  2. Leonardo Malagon says:

    Dear Lou,

    Hi, I have just found this picture online. I am studying a group of sawflies for my PhD here in Europe. I was wondering if either you did collect any of these specimens, or if you could share to me the exact locality and collecting information. I am very interested in these specimens. Please let me know.

    Thanks a lot,
    Leonardo

  3. Hi Lou Nigro,
    Your photo at top of webpage
    https://www.whatsthatbug.com/2012/05/06/sawfly-larva-possibly-cypress-sawfly/
    does appear to be Cypress sawfly, Susana cupressi. It is a sporadic pest in Southern California.
    Will you grant the University of California permission to reprint that photo in our publications and share it with others?
    Our uses would credit it;
    Photo by Lou Nigro, Used with permission.
    Thank you, Steve

    • bugman says:

      Steve,
      This is a seven year old posting. Lou might not see the request. WTB? does permit educational institutions to reproduce images and content from our site, so we grant UC permission to reprint the image in your publication. You can cite Lou Nigro as the photographer and please credit as courtesy of What’s That Bug? or whatsthatbug.com

  4. Hi Lou Nigro,
    Your photo at top of webpage
    https://www.whatsthatbug.com/2012/05/06/sawfly-larva-possibly-cypress-sawfly/
    does appear to be Cypress sawfly, Susana cupressi. It is a sporadic pest in Southern California.
    Will you grant the University of California permission to reprint that photo in our publications and share it with others?
    Our uses would credit it;
    Photo by Lou Nigro, Used with permission.
    Thank you, Steve

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