A collection of stromatoporoids from the Broken River Formation, North Queensland, is described. Thirty two species are ascribed to twelve genera. Ten new species are proposed, one new genus, Laminostroma, and one new family, Amphiporidae.
The study has concentrated on the taxonomic problems of the group and on its use in stratigraphic correlation.
A modified classification is proposed which places the major emphasis on microstructure of the tissue as a criterion of differentiation. The stromatoporoids in the collection have been placed in four families, Actinostromatidae, Stromatoporellidae, Stromatoporidae, and Amphiporidae. Some taxonomic units in the family Stromatoporidae previously considered genera, are here designated subgenera.
The species are compared with previously described stromatoporoids in order to assess their use in stratigraphic correlations. Three stromatoporoid faunas are recognised; the Laminostroma fauna, Stictostroma fauna and Actinostroma devonense fauna, which are considered Emsian, Couvinian and Givetian respectively. The ages thus determined for the stratigraphic units are in general agreement with those determined from rugose corals by Jell (1967), except that the Givetian Actinostroma devonense occurs below the base of the Givetian indicated by Jell. Although descriptions of overseas stromatoporoid faunas are still inadequate, particularly in the Lower Devonian, the group is shown to be of considerable value in correlation.