Palaemysis dunlopi Peach 1908 (Eocarida, Crustacea) from the Namurian (Carboniferous) of the western Midland Valley

Abstract

Synopsis Palaemysis is one of five eumalacostracan genera obtained from Namurian shales in the western Midland Valley of Scotland. On the basis of the preserved morphology alone, it was concluded that Palaemysis should be retained within the Eocarida rather than being assigned to any extant group. Palaemysis differs substantially from Anthracophausia despite having been previously considered as synonymous. These differences include the presence of a large rostrum in Anthracophausia, the shape of the telson and uropods, the shape of the abdominal pleura, and the presence of a large pair of anterior spinose appendages (mandibular palps) in Palaemysis. The three species of Palaemysis, P. dunlopi, P. couttsi, and P. tenuis, were first erected on the basis of poorly preserved tail fans. These species could not be adequately, morphometrically or morphologically, differentiated and only one species of Palaemysis is therefore recognised. The species of Palaemysis is taken to be that of the original type species, P. dunlopi.