Athrotaxites is an extinct genus of coniferous plants belonging to the family Cupressaceae,[2] known primarily from fossil material dating to the Jurassic and Cretaceous periods.[3] It is closely related to the extant Tasmanian genus Athrotaxis,[4] and is typically classified within the subfamily Athrotaxoideae.[4][5]
Athrotaxites is characterized by distinctive reproductive structures, particularly ovuliferous cones bearing multiple winged seeds, and leafy twigs with helically arranged scale-like leaves.[2][4][5]
Distribution
Fossils attributed to Athrotaxites have been recovered from a range of geographically and geologically diverse sites, indicating that the genus once had a broad distribution across the Northern Hemisphere during the Cretaceous period. In North America, well-preserved remains of Athrotaxites berryi have been described from the Aptian-aged Kootenai Formation in Montana and the Lower Blairmore Formation in Alberta, Canada, representing some of the earliest records of the genus on the continent.[4] Additional fossil material, including ovuliferous complexes assigned to another Athrotaxites species, has been found in the Upper Cretaceous Raritan Formation of New Jersey, USA. In Asia, Athrotaxites yumenensis was discovered in the Lower Cretaceous Zhonggou Formation in northwestern China, where it occurs abundantly in certain sedimentary layers.[2] Jurassic aged fossils been found in India,[6] Germany,[7] Madagascar[8] and Argentina.[3] A Jurassic aged fossil is known from the Morrison Formation in Montana.[9]
Ecology
Based on both fossil morphology and depositional context, it is suspected that Athrotaxites occupied cooler temperate environments with high moisture levels.[5] The adaptation for cooler temperatures can also be seen in its modern relative, Athrotaxis.[10]
↑ O. Appert. (1973). "DiePteridophyten aus dem Oberen Jura des Manamana in Sudwest-Madagaskar". Palaontologische Abhandlungen Memoires suisses de Paleontologie.
↑ A. J. Silverman. "Stratigraphy and economic geology of the Great Falls-Lewistown coal field central Montana". State of Montana Bureau of Mines and Geology Bulletin.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
