Late Carboniferous scavenging ostracods : feeding strategies and taphonomy

Direct fossil evidence of scavenging ostracods is rare. A convincing example, representing the earliest recorded occurrence of ostracods feeding on vertebrate carrion, is described from the Bowland Shale Formation (Kinderscoutian, Upper Carboniferous) of Derbyshire, UK. It consists of the anterior end of a shark (Orodus sp.) whose upper surface is crowded with adults and juveniles of the nektobenthic ostracod Eocypridina carsingtonensis Wilkinson, Williams, Siveter & Wilby, 2004 (Myodocopida: Cypridinidae). Extrapolation of their preserved density suggests that the entire carcass may have hosted over a thousand individuals. It presented a rare opportunity for benthic scavenging in the Widmerpool Gulf because it was sufficiently large to have protruded above the inhospitable, and probably soupy, substrate surface. Although not necessarily a necrophagous specialist, E. carsingtonensis appears to have been well adapted to rapidly locating and exploiting widely dispersed nekton food drops. Its absence from the background sediment suggests that it commuted to the shark over relatively large distances, probably from adjacent basin highs. This implies a well-developed chemosensory capability. The ostracods are interpreted as having been overwhelmed by sediment dislodged during the sudden collapse of the partially buried carcass.