(Yes, but can you dance to it?)

I have just for the first time heard Dohnanyi's "Ruralia Hungarica",
Op.  32a (David Korevaar, piano; Ivory Classics 64405-71008, 2000).
Aside from being quite nice, I had to laugh when I heard No.  4 (Vivace)
with its fast quintuplets.  It could be considered 15/8 or in 3/4 with
quintuplet eights for each quarter note, for example.  (Anyone know how
it's scored?)

(I like this disk. Mimi, you were right!)

But I wonder if it could really be the case that a "rural" Hungarian
tune was so rhytmically "pent-up".  I don't know much about these
"Ruralia", except what is in the liner notes, that they are "based on
traditional Hungarian melodies." Of course, "based on" leaves lots of
room for maneuver, but I read that Dohnanyi was pretty conservative, so
maybe they were actually inspired by some traditional tunes in five-beat
meters.  Any guesses?  Does anyone know other examples?

My own guess is that the inspiration was something in six beats,
shrunk to five, as is occasionally done.  E.g..  take triplets of the
form quarter/eighth // eighth/eighth/eighth and shrink the quarter to
an eighth.  (How does one write music in ASCII text?) Perhaps a Dohnanyi
expert on the list knows the answer.

It also got me wondering when the earliest surviving odd-time signatures
appeared.  Anyone have some early classical favorites, say, pre-1900?
Tchaikovsky's symphony number 6 has a "waltz" in 5/4 (second movement),
for instance.

P.S.  A percussion professor told me a joke a few decades ago: "How do
dummies count 7/4?" But I'm sure everyone here has heard it.

Rick