I was out picking the day's crop of cherry tomatoes from my sole surviving
vine (a long sad story) and spotted a miniature mud structure attached to
the underside of one leaf. Overall the structure looks to be 18-20mm long
and the opening is certainly no more than 2mm. Appearance is that of mud
and we certainly have a lot of mud dauber wasps around here so I know what
it looks like after insects have worked with it. On the theory that many
wasps parasitise harmful insects I've left this in place. I've seen no
inhabitants coming or going.

http://johnmcgaw.com/Uru/wasp_nest.jpg

Any ideas would be appreciated. I find nothing in my guide books.

--
John McGaw
[Knoxville, TN, USA]
http://johnmcgaw.com