The classic mid-Devonian Eospermatopteris localities, Gilboa NY, USA

Abstract

For over 150 years, the mid-Devonian Eospermatopteris stump cast localities comprising the “oldest known petrified forest” of Goldring (1927) at Gilboa, New York have rarely been accessible for study. In 2010–2013, we had the opportunity to appraise all three major sites. Presented here are observations focusing on botanical data that may prove useful for interpreting future sites. Eospermatopteris at Riverside Quarry consists of stem base casts/molds, and corresponding root mounds on a paleosol surface. Sizes, spatial distributions, and unusual occurrences of the root mounds are assessed. Trunks above the base are also observed as compressions showing features of outer cortex and probable vascular tissues, as interpreted from previous examples. An arboreal isoetalean is noted on the paleosol along with an enigmatic mound possibly representing a Stigmaria-like root system similar to that described at Cairo NY. Details of aneurophytalean stems on the paleosol surface are presented including evidence of attached lateral branch systems, or possible rooting structures of small size. The paleosol at Gilboa Dam is remarkably similar to that at Riverside Quarry, but with carbonaceous remains much better preserved. Eospermatopteris base casts and root mounds are present along with probable aneurophytalean stems showing abundant evidence of attached lateral branches that are themselves profusely branched. The Manorkill locality exhibits weathered Eospermatopteris casts that outcrop along a ledge offering profile views. The Gilboa localities are significant in providing probably the best botanical data on rooted and close to in place floral elements from a mid-Devonian paleosol to date.