That's the problem; you can't prove a negative. All it takes to prove that a species is still extant is to find a living specimen. That's positive proof. But proving a species is extinct is impossible; not being able to find a living specimen doesn't mean that they don't exist...just that you can't find one.
How many times have we read about a species that was officially considered extinct...only to pop up in some remote location, or possibly in this case in some "secret" breeding facility? I'm not referring here to animals thought to have died out millions of years ago, like the Coelacanth; I'm talking about recent supposed "extinctions" that were re-thought when a small population of said critter is located in some isolated spot. I believe the Red-tailed Black Shark was called extinct in the wild, only to come back from the dead when some wild ones were discovered in some Asian stretch of river.
In the birding world, the Ivory-billed Woodpecker is a well-known example. I have lost track of the number of times it's been declared extinct...but then a sighting is reported in a remote section of swampland in the southeast U.S. or more recently in Cuba...and the chase is on again. People really, really want a spectacular bird like the Ivorybill...or a spectacular fish like the ST...or some cryptozoological marvel like the Yeti or Nessie or whatever...to be a real, live thing; they will go to great extremes to "prove" these things exist.
In the case of the ST, there also enters into it the difficulty of determining exactly what species a given individual fish belongs to. The dang thing is right there in front of you, on display in a tank of clear water...and we can't agree what it is. Species designations aren't engraved in stone, and they aren't universally agreed upon, and they certainly aren't unchangeable. Every living thing on earth exists on a broad spectrum of life at its own given point. We humans...who know everything...arbitrarily draw lines here and there on that spectrum to delineate genera, species, subspecies, etc.and those lines are constantly being shuffled around and re-drawn. We argue about where the lines should be, as well as how many there are at all. DNA analysis allows us a better understanding of which animals are more closely or less closely related to each other, and how long ago they diverged...but it is still an arbitrary process when it comes time to say "these are two species" or "they are merely subspecies" or whatever.
And now, in the case of the ST...the inexplicable lust to own something "different" or "better" or "rarer" than what the next guy owns causes people to spend huge sums of money for that special thing...so of course they will "put their mouth where their money is" and defend their individual stances with a vengeance.
The fish don't care what we think. Good for them!
