| Zosterophyll Temporal range:
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| Zosterophyllum species fossils; left: with coiled (circinate) branch tips, right: with sporangium | |
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| Zosterophyllum Life restoration from MUSE | |
Scientific classification 
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| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | Lycophytes |
| Plesion: | †Zosterophylls |
| Order | |
The zosterophylls are a group of extinct land plants that first appeared in the Silurian period. The taxon was first established by Banks in 1968 as the subdivision Zosterophyllophytina; they have since also been treated as the division Zosterophyllophyta or Zosterophyta and the class or plesion Zosterophyllopsida or Zosteropsida. They were among the first vascular plants in the fossil record, and had a world-wide distribution. They were probably stem-group lycophytes, forming a sister group to the ancestors of the living lycophytes.[1] By the late Silurian (late Ludlovian, about 420 million years ago) a diverse assemblage of species existed, examples of which have been found fossilised in what is now Bathurst Island in Arctic Canada.[2]
- ^ Gensel, P.G. (1992), "Phylogenetic relationships of the zosterophylls and lycopsids: evidence from morphology, paleoecology, and cladistic methods of inference", Annals of the Missouri Botanical Garden, 79 (3): 450–73, doi:10.2307/2399750, JSTOR 2399750
- ^ Kotyk, M.E.; Basinger, J.F.; Gensel, P.G. & de Freitas, T.A. (2002), "Morphologically complex plant macrofossils from the Late Silurian of Arctic Canada", American Journal of Botany, 89 (6): 1004–1013, doi:10.3732/ajb.89.6.1004, PMID 21665700