An older revision of Wikipedia article on Spiccato has an image showing what looks like a staccatissimo, with the caption "Notation for spiccato."
I question that—it may be that strings can use spiccato to play staccatissimo, but that doesn't mean that staccatissimo = spiccato. Is Wikipedia correct? Is there any symbol used to indicate that a specific note should be played spiccato?
Spiccato, like most specific bowing techniques, is not often indicated explicitly in scores. The staccatissimo mark on that page does indeed often get translated as spiccato when given to a string player, but there are plenty of situations in which a regular staccato is interpreted as spiccato as well. Staccatissimo in Mozart, especially on repeated notes, is usually performed spiccato; Staccato dots in Bach, however, are often performed in the same way. I can certainly think of some situations where I've used spiccato even in situations with no markings at all, for example during a fast, repeated-note passage in music with a very light affect.
In other words, spiccato is more like a tool in a string player's interpretive tool chest--one that is very often effective for staccatissimo-marked passages. Of course, if the composer wishes to ensure that interpretive choice, they can add a written indication to that effect. That's the only explicit spiccato indication I've ever seen: either marked "spiccato" or "bouncing bow" or something to that effect.
As always, I recommend the Dolmetsch page, which in fact does not list a symbol for spiccato / sautille. I think all the sheet music I've seen writes out the word over (or leading) the notes in question.
