You may consider sequencing COI to figure out what organisms are there.
Cheers, Sergei
13.10.2017, 21:38, "Paul S. Robbins" <[log in to unmask]>:
The spots remind me of tachinid eggs I have seen on adult Phyllophaga captured in light or pheromone traps.

Sent from my iPhone

On Oct 13, 2017, at 11:09 AM, François Génier <[log in to unmask]> wrote:

At one point I was thinking they could have been fly eggs embedded in some kind of « glue » so the eggs could be dispersed with the beetles… but the microscopic preparation seems to say otherwise.




De : Scarab Beetle Taxonomy Discussion List [mailto:[log in to unmask]] De la part de Bruce Gill
Envoyé : 13 octobre 2017 10:42
À : [log in to unmask]
Objet : Re: Query RE: mysterious yellow spots on Onthophagus taurus


Now I'm very interested in learning what these "plaques" are, as shown in DSCN3724.  I've observed them on numerous genera of Scarabaeine dung beetles from the Neotropics and elsewhere. At an Ent. Soc. of America symposium on Insect-Fungus relationships some 20+ years ago, the speaker showed images of very similar structures on the pronota and elytra of beetles and said they were Laboulbeniales.  If these are not labouls, then perhaps they are another group of fungi.





On 2017-10-12 17:06, Mikhail F. Bagaturov wrote:

Than it shall be an integument defects.

All the best, Mik


Четверг, 12 октября 2017, 23:41 +03:00 от Alberto Ballerio <[log in to unmask]>:

I sent the photo of the Onthophagus taurus
specimen to Prof. Walter Rossi, an authority on
Laboulbeniales and he told me that the mistery
spots do not belong to the order Laboulbeniales.
Best regards,

At 18:08 12/10/2017, you wrote:
>These look very typical Laboulbeniales. Some of
>the other blotches look less distinctive! Best wishes, Robert.
>From: Scarab Beetle Taxonomy Discussion List
>[mailto:[log in to unmask]] On Behalf Of Angel Solis
>Sent: 12 October 2017 16:45
>To: [log in to unmask]
>Subject: Re: Query RE: mysterious yellow spots on Onthophagus taurus
>I have seen here in Costa Rica many cases like
>the one Kevin shows in his photo, we also have
>clear cases of Laboulbeniomycetes like those
>shown in my photo on a Dichotomius centralis.
>However the ones in Kevin's photo look different from those in my photo:
ngel Solís


Dr. Alberto Ballerio
Viale Venezia 45
I-25123 Brescia
e-mail: [log in to unmask]


All the best, Dr. Mikhail F. Bagaturov

IUCN/SSC Amphibian SG and Conservation Planning SG,
Academic Member of Athens Institute For Education & Research (

Author of Theraphosids of the World: 

Sergei Tarasov, Ph.D. 
Postdoctoral Fellow
University of Tennessee, Knoxville
National Institute for Mathematical and Biological Synthesis (NIMBioS)
Email: [log in to unmask]