Diploporus

Diploporus is an extinct genus of conifers in the yew family Taxaceae, containing the single species Diploporus torreyoides known from the middle Eocene of north central Oregon and the Late Paleocene of south central North Dakota. The species was first described from a series of isolated fossil seeds in chert.

Diploporus torreyoides has been identified from a single location in the Clarno Formation, the Clarno nut beds, type locality for both the formation and the species. The nut beds are approximately 3 kilometres (1.9 mi) east of the unincorporated community of Clarno, Oregon and currently considered to be middle Eocene in age, based on averaging zircon fission track radiometric dating which yielded an age of 43.6 and 43.7 ± 10 million years ago and Argon–argon dating radiometric dating which yielded a 36.38 ± 1.31 to 46.8 ± 3.36 mya date. The average of the dates resulted in an age range of 45 to 43 mya. The beds are composed of silica and calcium carbonate cemented tuffaceous sandstones, siltstones, and conglomerates which preserve either a lake delta environment, or alternatively periodic floods and volcanic mudflows preserved with hot spring activity. An unidentified species of Diploporus has been reported from the Sentinel Butte Formation near the town of Almont, North Dakota and the Beicegal Creek, North Dakota. The age of the formation is based on the recovery of late Tiffanian mammals in the upper section of the formation along with the floral and palynological assemblages of the formation.