DACRYOCONARIDS OF THE EIFELIAN (MIDDLE DEVONIAN) STONY HOLLOW EVENT

The Stony Hollow Event (SHE) is understood to record an incursion of tropical waters into the subtropical Appalachian Basin, during which there was also an incursion of Old World faunal elements and a destabilization of the long-standing Schoharie/Onondaga fauna. At Cherry Valley, NY, the SHE is recorded in the upper meter of the Bakoven Shale, as well as the Hurley and Cherry Valley members of the Oatka Creek Formation. The lowermost unit of the Hurley Member is the Chestnut Street Bed, which was the focus of this study, for it has the highest diversity of dacryoconarids (dacs) within the SHE interval. Our sampling location was a stratigraphic interval of 2.6m in an exposed road cut on Chestnut Street, 3.8km east of Cherry Valley, NY.

Dacs in the Chestnut Street Bed include a diversity of forms representing at least fine genera. Perhaps the most diagnostic and abundant dac is Costulatostyliolina strigata, which first occurs in the upper Bakoven and is not known to occur above the the Chestnut Street Bed. Nowakia sulcata cf. antiqua and an undescribed species of Striatostyliolina, which first occurs at the base of the Nedrow Member (= Basal Chotec Event) of the Onondaga Limestone, also top out in the Chestnut Street Bed. The Chestnut Street Bed records the lowermost occurence of Nowakia Halihanensis, which last occurs just above the top of the Oatka Creek's East Berne member, as well as the lowermost known occurence of the genus Homoctenus in the Appalaichan Basin. These are joined by at least one form of Styliolina and several undescribed forms of Viriatellina and Nowakia, which are known to occur above the uppermost extent of the Cherry Valley Member that marks the top of the SHE interval.