Location: North-central Pennsylvania, USA, along the southern margin of the ancient continent, Euramerica.
Time Period: Late Devonian (specifically, the Famennian age, roughly 375-359 million years ago).
Fauna
- Early Tetrapods: Animals like Hynerpeton and Densignathus hunted in the shallow waters and would have ventured onto land for short periods.
- Abundant Fish: Various species of fish, including lobe-finned fish (relatives of tetrapods) and armored placoderms, filled the waterways.
- Invertebrates: The presence of trigonotarbids (arachnids) and myriapods (like millipedes) indicate a developing terrestrial arthropod ecosystem.
Dominant Vegetation:
- Archaeopteris Forests: Giant, tree-like progymnosperms called Archaeopteris formed dense forests. These were among the world’s first true trees, reaching heights of up to 60 feet (18 meters).
- Fern Glades: Rhacophyton, an extensive, shrubby fern, carpeted the forest floor and wetlands.
- Lycopsid Wetlands: Scale-trees resembling giant club mosses added to the wetland diversity
- Early Seed Plants: Patches of the earliest seed plants began to appear, taking advantage of disturbed areas such as those created by wildfires.
Landscape:
- Floodplain environment: the area was part of a vast river system and its floodplains. The landscape was dynamic, with changing river channels, swamps, and areas of occasional fire disturbance.
- Lush vegetation: Despite periodic disruptions, the environment was predominantly green. Forests and wetlands thrived in this warm and humid climate.
Significance:
Catskill formation offers a remarkably vivid snapshot of a critical moment in Earth’s history:
- The Rise of Forests: The Archaeopteris forests represented a major step in the evolution of terrestrial plants. These trees created new habitats and profoundly altered the landscape’s structure.
- Terrestrialization: The fossils of early tetrapods and land-dwelling invertebrates highlight the ongoing transition of life from water to land.