The New Zealand Zoophycos

Abstract

Occurrences of Zoophycos are described and figured from the Amberley Limestone (Oligocene) in North Canterbury. The structure consists of a flattened to markedly conical helical slab of sediment. Interpretation of the structure as a body fossil is rejected on the basis of cross-cutting relationships of slabs to each other and to worm burrows, morphological dissimilarities to recent organisms, and mechanical difficulties in accounting for burial and preservation. Interpretation as an inorganic sedimentary structure is also rejected. The New Zealand Zoophycos is inferred to be a trace fossil, formed by a sediment-feeder which operated essentially below the sediment-water interface. The complex structure of the slabs reflects an efficient search-pattern; behavioural eccentricities account for differences among patterns.