Dimorphic Flower Longhorn:

Subject: orange and black bug
Location: Sierra foothills at 2000′ in Weimar, CA.
May 25, 2014 1:34 pm
I found this on a faded arilbred iris. Sorry the picture is blurry. I am in the Sierra foothills at 2000′ in Weimar, CA. I’d guess it’s about 2/3 inch long.
Signature: Carolyn

Dimorphic Flower Longhorn
Dimorphic Flower Longhorn

Dear Carolyn,
Your image is indeed quite blurry, which makes us sad because we believe we have correctly identified your female Dimorphic Flower Longhorn,
Anastrangalia laetifica, on BugGuide, and it represents a new species on our site.  Even though your image is blurry, the distinctive markings leave little doubt as to its identity.  The term Dimorphic in the name refers to the obvious visual differences between the sexes, which makes them appear to be different species.  Females are colored similarly to your individual, while males are black or brown.

Thank you very much! I tried finding it myself using the BugGuide, but could not even get there from Insecta.  Is there a way to browse the categories that would more easily lead me to the right page.  I completely agree that this BugGuide pictures of this species clearly identify my bug.  I could not find information anywhere on what they eat – apparently plants, but nectar?  Petals, leaves?  Do you know?  (My search, however, led me to much fascinating information, for example, about butterfly color production by forming gyroids.)
Thank you again, and thanks in advance if you find any info about their feeding.
Carolyn Spier

Hi Carolyn,
We have no advice on how to best browse BugGuide as one needs a basic understanding of insect orders before being able to search successfully.  The same is true of our site, however, our search engine works quite well if you type in descriptive words, however, as we stated earlier, since this is a new species for our site, you would never have found your species identification on our site.  We think of Flower Longhorns as being nectar feeders, however, BugGuide has this to say on the family Cerambycidae information page:  “Many adults (esp. the brightly colored ones) feed on flowers.  Adult feeding requirements are variable, with some species taking nourishment from sap, leaves, blossoms, fruit, bark, and fungi, often not associated with larval hosts; others take little or no nourishment beyond water.”

Thank you so much for taking the time to answer me, twice!  I prefer to believe that this brightly colored female is the nectar sucking type – until proven otherwise.  I wonder what the larvae eat, though.

Hi again Carolyn,
The original BugGuide link we provided for you was to a photo and it does include food information.  According to BugGuide Larvae are borers in “Pinaceae” which is the family that includes pine as well as cedar, fir, hemlock, larch and spruce, though the Dimorphic Flower Longhorn might only use one genus as the host.  This information is provided under life cycle:  “According to Dennis Haines (pers. communication, HW) floral hosts of adults include Calochortus (Liliaceae); Ceanothus (Rhamnaceae); Achillea, Heracleum (Apiadaceae); Eriodictyon (Hydrophyllaceae).” 

Hi Daniel,
I went again to that original link you sent.  Now I see the tabs for the other info.  Thanks!  It fits that I live on serpentine in pine/oak woodland.

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