Pityostrobus Makahensis, a New Species of Silicified Pinaceous Seed Cone From the Middle Tertiary of Washington

A single structurally preserved ovulate cone forms the basis for the description of a new species of Pityostrobus from the early Oligocene of the Olympic Peninsula of Washington. The specimen consists of about two‐thirds of a cylindrical cone. In living condition the cone was 8–10 cm long and 3.5–4 cm in diameter. Critical features of the cone include decurrent bract bases, an elongate bract‐scale adnation, perpendicular disposition of the proximal part of the scale, and seeds with vesciculate seed coat. An unusual feature of the cone is a distinctive cortical region of thin‐walled parenchyma, mineral‐filled lacunae, and resin canals. This region can be traced to the adaxial side of the scale where it can be recognized by an extensive development of resin canals in the adaxial ground tissue opposite the seed cavities, and by distinctive lacunae around the vascular bundles. The fossil shares several significant characters with modern cones of Abies, Pseudotsuga, Larix, Tsuga, and Picea, thereby calling to question the abietoid/pinoid division of the family, or suggesting that abietoid and pinoid genera of the early Oligocene had not yet diverged to the extent seen in the modern flora.