The MGS Forum

Gardening in mediterranean climates => Pests and diseases => Topic started by: Pallas on March 28, 2016, 09:07:47 PM

Title: In spring, a young beetle's thoughts turn to white roses
Post by: Pallas on March 28, 2016, 09:07:47 PM
My rose 'Madame Alfred Carrière' has just burst into bloom and, right on cue, today I picked 4 white-spotted rose beetles (Oxythyrea funesta) off the white flowers. My callas are also getting going and they love those too. Boo.

Interestingly, I haven't seen any evidence of them on the lemon blossom even though the tree is next to the Madame rose. Fingers crossed.

I'd be very interested to hear from those who try the pheromone traps. The Junta de Andalucía has authorised a mixture of pesticidal compounds for use against this beetle in vineyards, but obviously this is aimed at commercial growers and qualified pesticide handlers.

I will keep hand-picking them, but as the eggs are laid underground, I think this is just firefighting... hey-ho.
Title: Re: In spring, a young beetle's thoughts turn to white roses
Post by: MikeHardman on May 04, 2016, 09:23:06 PM
Not an answer to your question, but some more info on white spotted rose beetles, in case folks equate that common name with just that one species Oxythyrea funestra...

Several of the species of Oxythyrea are confusable, which can result in some online references being misnamed - so beware.
Here's a page allowing comparison of spotting in three species
- http://www.kaefer-der-welt.com/oxythyrea.htm
However:
- there are more than a dozen species, and I have yet to find a key / photo-comparator / distribution comparator that covers them all
- it is not just the spotting (underside as well as topside) that differentiates the species; hairiness also needs to be considered, as shown in the key in this paper - http://www.entomology.org.il/sites/default/files/pdfs/Rittner.pdf
 
The Latin naming issue is not helped by several species being loosely referred-to as 'white-spotted rose beetle', although in a sense it is handy to have the broad English name to fall back on when one cannot ID a particular specimen as far as species.
 
If in doubt about species ID, I suggest contacting Guido Sabatinelli, who runs the site
"The Scarabs of the Levant, Syria, Lebanon, Jordan, Palestine, Israel, Sinai"
- http://www.glaphyridae.com/index.html
Here is his page on O. cinctella, for instance, including excellent diagnostic diagrams
- http://www.glaphyridae.com/Cetoniinae/Ox_cinctella.html
 
Here are the ones in my garden in western Cyprus, enjoying my red hot pokers
(http://www.nhm.ac.uk/natureplus/servlet/JiveServlet/downloadImage/2-81551-118448/450-600/Oxythyrea+noemi+on+Kniphofia+uvaria%2C+Cyprus%2C+by+Mike+Hardman.jpg)
Refs:
- http://www.kaefer-der-welt.com/oxythyrea_noemi.htm
- http://www.naturewonders.org/picture?/2517

Mike
Title: Re: In spring, a young beetle's thoughts turn to white roses
Post by: Pallas on May 07, 2016, 01:39:50 PM
Thank you, Mike, that is fascinating! I pick them out and tread on them as quickly as before they fly off, so I have never noticed the admittedly subtle differences. I'll have to take a closer look next time (not that there's any shortage of them :-[ ).