PITYOSTROBUS MILLERI SP. NOV., A PINACEOUS CONE FROM THE LOWER CRETACEOUS (APTIAN) OF SOUTHWESTERN RUSSIA

A new species of permineralized Pityostrobus cone, Pityostrobus miller i Falder et al., sp. nov. has been discovered in a calcareous nodule f rom shallow marine sediments of Early Cretaceous (latest Aptian; Clans enian) age in the Caucasus Mountains in southwestern Russia. Nodules o f this type also contain wood fragments, gastropods, bivalves, and an extremely rich assemblage of well preserved cephalopods. Russian spore and pollen analyses indicate that deposition in this region may have occurred during a temperate climate regime. The cone is cylindrical, a bout 2.5 cm in diameter and individual scales contain up to 17 resin c anals and 18 vascular strands. Although the fossil displays many featu res of modem Pinus cones, including inflated scale apexes, resin canal s abaxial to Vascular tissue in scale base, and scale strands curved o n the adaxial side, it cannot be assigned to Pinus because the bract a nd scale trace are not united at their origin. Tunneled borings in the cortex of the cone axis are tightly packed with frass, and resemble t unnels of modern cone boring beetles such as Conophthorus. This cone f urther documents the worldwide diversity of pinaceous conifers during the Cretaceous, and demonstrates a well developed syndrome of insect h erbivory in the Pinaceae by the late Mesozoic. (C) 1998 Elsevier Scien ce B.V. All rights reserved.