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In articles I've read, evidence of dark matter (rotation of galaxies / gravitational lensing / galaxy collisions etc) is presented at galactic scales.
Are there examples of dark matter at smaller scales than this?
One possibility I could think of, would be a misidentified 'silent' black hole vs a cold dark matter clump. This example is probably a completely incorrect assumption on my behalf, but I'm curious to know if we do have evidence, or even possibilities at this scale.
One could argue that the rotation curves of galaxies are intra-galactic evidence, since it requires the somewhat continuous presence of dark matter across the galaxy.
If you want smaller scales, the smallest systems where dark matter is firmly established are dwarf galaxies; these are dark matter dominated.
Finally, there are tidal streams. Some of those exhibit e.g. holes and other structures that some have interpreted as evidence for dark matter interacting with those streams. While that's an extremely interesting possibility, it's not firmly established as evidence for dark matter.
Concerning your misidentified silent black hole: primordial black holes are dark matter candidates. But none have yet been found, despite searches for them. More generally, MACHO searches look for such objects.
