Iron Cross Blister Beetle

Hi. Recently my son found this beautiful bug near our house in Glendale, AZ. I’m attaching a picture. It has a bright red head, and it’s back is yellow with a black pattern dividing it into 4 parts. It’s the first and only time we’ve seen one.
Any idea?

Ironcross Blister Beetle
Ironcross Blister Beetle

Dear Wes,
I contacted our sources at the Natural History Museum in Los Angeles, and he provided the following information.

Thanks for sending the beetle photo. It is in the Blister Beetle family: Meloidae. You can probably look it up on the internet…try under the genus name Lytta. Some of these beetles exude a toxic liquid which can cause blisters on the skin. I’m not sure this one does that.
Hope this helps you!
Take care. Brian Harris
Entomology Section
Natural History Museum LA Co.

A web search did not turn up a more exact identification, but there is this site which has a photo of a close relative Lytta magister which also has a red head and legs. I do have some interesting background information on the genus however. A blue-green colored European relative Lytta vesicatoria, is known by the common name Spanish fly: Perhaps the most famous `aphrodisiac’ of folk lore is `Spanish Fly’ made from the dried beetle _Cantharis_ (Lytta) _vesicatoria_, which is widely found in areas of southern Europe. The active ingredient of the prepared insect is cantharidin, and the powdered product contains around 0.6 percent of the substance. Sometimes a tincture of cantharidin is made, and the fatal dose is usually reckoned at 1.5 to 3 grams of the powder, or about 200 millilitres of the tincture. I have not given up entirely on the identification. I will be making a trip to the insect museum in Riverside in the near future. Thanks again for the awesome photo which is currently on my desktop at work.
Have a great day.

Editor’s Note: Continued research has identified this little beauty as a member of the Blister Beetle Family known as Soldier Beetles, Tegrodera erosa Lec. or Tegrodera latecincta Horn. “They are 17-30 mm. long; the head red; the prothorax dusky red; the antennae, legs, and remainder of the body shining black; and the elytra golden yellow, reticulated, and with black margins, a black median belt, and black apices. In the former specioes the black markings of the elytra are very obscure, while on the latter they are strongly pronounced. The beetles ordinarily feed upon the native sage brush, artemisia, and other plants, but frequently invade alfalfa fields and do much damage.” according to Essig in Insects and Mites of Western North America.

Update: (11/09/2008)
After doing our site migration and checking that everything migrated, we found this posting that was never correctly identified as an Iron Cross Blister Beetle

Another Iron Cross Blister Beetle
We have Hundreds maybe Thousands on the ground and
all over our house. Please help us as my 6 and 4 year olds are scared and me too!

Iron Cross Blister Beetle
Iron Cross Blister Beetle

We were unable to anwer this reader who should be somewhat afraid of Blister Beetles which can cause a skin reaction.

2 thoughts on “Iron Cross Blister Beetle”

  1. Is it common for the Iron cross beetle to attack!
    I was spraying them with bug spray as I must have had some 2-3 hundred in my backyard and was attacked toward my head by 2 of them!
    It was like they were on a mission.
    Been at this property 3 yrs, first time I’ve ever seen them!
    Nowhere can I find that they fly!
    Thanks for the info.
    Queen Creek ,AZ


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