The trace fossil Zoophycos Massalongo in the Carboniferous (Mississippian) of Alnmouth, Northumberland

Abstract

The Mississippian strata of England and Wales, mainly limestones, are rich in body fossils, but deficient in trace fossils. Herein, a coastal locality rich in the spiral burrow Zoophycos isp. is described from Alnmouth, Northumberland. Although originally reported in 1930, this site and its trace fossils are only illustrated and described in detail for the first time herein. The locality is in the Lower Foxton Limestone, Stainmore Formation, Yoredale Group; Arnsbergian substage, Namurian stage, Mississippian. Zoophycos isp. are common on two bedding planes, the lower of which exposes c . 460 m 2 . Traces are flat, plume-like and preserved in negative epirelief. Spreiten are fine to coarse and outline of the burrow varies from circular to more rectangular. Specimens are numerous, but water-worn and poorly preserved. The Lower Foxton Limestone was likely deposited in a shallow water setting. Trace fossils in Mississippian limestones remain problematic, but this is most probably due to a combination of taphonomic, palaeoenvironmental and collector bias, or a mixture of all three. That is, what is difficult to collect fails to find its way into collections, survey, university, museum or private, and, ultimately, into print. They are there, but they offer many problems for the collector.