"Normal" TSN is not a single fish but a genus consisting of either 4 or 8-9 species - the scientists cannot agree yet, but anyhow, there is 4-9 described genuine species.
Your fish is a man-made hybrid, produced in a Petri dish. A cross between one of the TSN species, likely fasciatum, and an achara catfish aka marbled pim catfish aka Leiarius marmoratus, a fish from the same family but a different genus.