What it is
A seed-bearing tree with long leaves shaped like tongues, each with a midrib and a net of fine veins. Its fossil roots have their own name, Vertebraria. They look like little ladders.
Why it matters
Across the southern supercontinent Gondwana, Glossopteris forests grew on wet lowlands as the great ice sheets melted back. When the trees died they fell into waterlogged ground and did not fully rot. Buried layer on layer, they became coal, including the coal now burning at Jharia in eastern India.
A tree of the far south
Its relatives grew even nearer the pole. Fossil wood from the Beardmore Glacier in Antarctica has tree rings from about 80 to 85 degrees south. The scientists who studied it think these trees dropped their leaves each year, to get through months of winter darkness.