Skolithos

Skolithos (formerly spelled Scolithus or Skolithus) is a common trace fossil ichnogenus that is, or was originally, an approximately vertical cylindrical burrow. They can reach lengths of up to about 35 cm (14') and diameters of up to about 5 cm (1.6'). Skolithos burrows range in age from early Cambrian to the present and are found throughout the world. They occur in sediments and sedimentary rocks, primarily sands and sandstones. They are typically marine in origin, and are commonly associated with high-energy environments close to the shoreline. They have also been reported from freshwater lacustrine settings, but have rarely been described from carbonate rocks. The famous 'Pipe Rock' of northwest Scotland is a well-known example of Skolithos. The 'pipes' that give the rock its name are closely packed straight Skolithos tubes that were presumably made by a worm-like organism. Skolithos linearis, found in the Blue Ridge Mountain region, is the oldest known trace fossil in Virginia. Trypanites is similar in form but is excavated in hard substrates. Also somewhat similar are Ophiomorpha and Diplocraterion.