When did the Lepidodendron tree go extinct?

I have a large chunk of sigillaria (first cousin of the Lepidodendron) from Arizona that my great-uncle obtained many, many decades ago. The other fossils were Triasic, I believe. But the Lepidodendron and Sigillaria were Carboniferous trees, which flourished when our atmosphere was 30% more dense than it is now. Could they have survived into the Triasic?