Invertebrate ichnofossils from the Upper Triassic Bull Canyon Formation, east-central New Mexico

Invertebrate ichnofossils from the Upper Triassic Bull Canyon Formation (Chinle Group) in eastcentral New Mexico are identified as Diplichnites triassicus, Palaeophycus tubularis, Skolithos isp. and Scoyenia gracilis, and occur in two distinct ichnofossil assemblages. One assemblage consists of Palaeophycus, Skolithos and Scoyenia, and is found in abandoned fluvial channel deposits, which is similar to other Triassic ichnofossil assemblages from this lithofacies. The other is a monotaxial ichnofossil assemblage of Diplichnites, which is anunusual occurrence in Triassic red beds, and reflects a different lithofacies deposited in a microenvironment characterized by active water flow.