Article: Fish trails from the early Permian of South Africa
In the lower Karroo Dwyka and Ecca Series there are widespread trace fossils which can be attributed with reasonable confidence to fish. Each trail is composed of a bilaterally symmetrical set of up to nine distinct waves. The waves in a set share a common wavelength and direction of travel, but they vary in form and amplitude. The marginal pair of waves has the lowest amplitude; this pair was apparently left by the pectoral fins. Pelvic appendages appear to have been responsible for the remaining paired wave(s). The unpaired wave has the greatest amplitude and was probably produced by the caudal fin. A new ichnogenus is erected to contain these trails. It is divided into three ichnospecics on the basis of increasing complexity : Undichna bina, U. simplicitas, and U. insolentia.