Psilophytopsida
Quick Summary
The Psilophytopsida represents the most primitive group of pteridophytes, which are seedless vascular plants. This group did not survive past the Devonian Period.1
Key characteristics of Psilophytopsida:
* Structure: Possessed a naked stem with sporangia (spore cases) at the tips. Some members had lateral sporangia but lacked true leaves, often exhibiting primitive dichotomous branching.1
* Evolutionary Significance: Considered a basic stock from which other plant groups evolved.1
* Examples: Included genera like Cooksonia and Rhynia.1
These plants were herbaceous colonizers of moist environments, typically less than 30 cm tall, and were not differentiated into distinct stems, leaves, and roots. They possessed stomata, indicating they were photosynthetic.2
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phylogenyEvolution of land plants…early vascular plants are called psilophytes. The development of seeds arose from the retention of the embryo inside maternal tissue. Early seed ferns gave rise to the gymnosperm group, including pines, spruces, and firs. Flowering plants, known as angiosperms, probably came from the gymnosperm phase and have two subgroups: the…
Read More…early vascular plants are called psilophytes. The development of seeds arose from the retention of the embryo inside maternal tissue. Early seed ferns gave rise to the gymnosperm group, including pines, spruces, and firs. Flowering plants, known as angiosperms, probably came from the gymnosperm phase and have two subgroups: the…
Read More- prefern
…the first land plants, the psilophytes, of the Silurian and Devonian periods (438 to 360 million years ago), and the ferns and seed-ferns that were common land plants later in time. The preferns appeared in Middle Devonian times (about 380 million years ago) and lasted into the Early Permian Epoch…
Read More…the first land plants, the psilophytes, of the Silurian and Devonian periods (438 to 360 million years ago), and the ferns and seed-ferns that were common land plants later in time. The preferns appeared in Middle Devonian times (about 380 million years ago) and lasted into the Early Permian Epoch…
Read More