Answer;
Seedless plant.
The fossil of a plant reveals that it produced spores that were used for reproduction. It was a seedless plant.
Explanation;
-Seedless vascular plants are plants such as fern and horsetails, liverworts, mosses; which contain vascular tissues, but do not produce flowers or seed.
-These plants reproduce using haploid , unicellular spores instead of seeds.
-These plants have life cycles with two distinct stages; one in which spores are produced and one in which sex cells are produced.