Wikipedia says alveolar clicks are found only in Africa/Australia, which isn't true at all.
For instance, there's the one usually done twice in rapid succession with the tongue against the upper side teeth/gums - to "gee up" a horse, indicate "mock-conspiratorial" agreement, etc.
So far as I know, we don't even attempt an onomatopoeic written representation of that one, but the one formed by suction against the back of the front teeth/palate is normally written as either "tut" or "tsk". Sometimes people actually say "tut" or "tut-tut" (presumably, influenced by the written form).
But I've never heard anybody say anything remotely resembling "tsk". So where does the "k" come from in that written representation?