a clade including equisetophytes (horsetails), psilotophytes (whisk ferns) and all eusporangiate and leptosporangiate ferns. Our maximum-likelihood analysis shows unambiguously that horsetails and ...

Charcoal accounted for about 6%. The majority of those leaves were from leptosporangiate ferns, with just a tiny amount from cycads (an ancient group of seed plants) and even less from conifers ...