Pinuxylon woolardii; ray cells; Miocene strata; Oregon
Specimens of the new species Pinuxylon wollardii have been collected from Miocene strata near Kurkee, OR. These petrified specimens are unique in that, due to weathering, individual tracheids and ray cells can be separated for detailed SEM studies. This species is characterized by its high number of ray cells; numerous rays; large resin ducts which are commonly paired; primarily uniseriate pitting, two to five (usually three) small, oval or cirular pinoid pits per crossfield; and smooth walls on its transverse (ray) tracheids. The latter character relates this species to taxa in the subgenus Haploxylon of Pinus. Pinuxylon woolardii is most similar to the fossil species Pinuxylon parryoides and the extant species Pinus aristata, P. cembroides, P. edulis, P. monophylla and P. balfouriana. These modern species live in drier environments and at high elevatiosn that that suggested by the Miocene leaf floras which occur near the locality of P. wollardii.