Monograph: Lower and Middle Devonian conodonta from the Broken River embayment North Queensland, Australia

Limestones of the Siluro-Devonian Graveyard Creek and Broken River Formations in the Broken River Embayment, north Queensland, contain diverse, though unevenly distributed, conodont faunas. Seven major units, the Jack Limestone Member of the Graveyard Creek Formation and the Martin's Well, Dip Creek, Chinaman Creek, Lockup Well Limestone Members and lenses Dmb_E and Dmb_F of the Broken River Formation were examined. Seventy-seven conodont form species and subspecies, referable to twenty form genera, are described; seven species (Coelocerodontus reduncus, Neopanderodus aequabilis, Ozarkodina playfordi, Scolopodus erectus, Spathognathodus palethorpei, Spathognathodus n. sp. A, Synprioniodina scalena) and one subspecies (Polygnathus foveolatus serotinus) are new. Although a continuous conodont succession could not be established, eight stratigraphically significant conodont faunas are recognizable. These comprise (in ascending order, with deduced ages): the eosteinhornensis (Ludlovian), pesavis (middle-late Siegenian), exiguus (middle-late Siegenian), Spathognathodus n. sp. (early Emsian), foveolatus-palethorpei (late Emsian), linguiformis cooperi (early Couvinian), pseudofoliatus (late Couvinian-early Givetian), and brevis (Givetian) faunas. The faunas allow an accurate appraisal of stratigraphical relationships within the Broken River Embayment and, though hampered by the apparent endemism of certain form species, their correlation within eastern Australia is effected. Intercontinental correlation shows that eastern Australian early Devonian conodont faunas are better related to western North American faunas than to those of the European type sequences; this may indicate some degree of conodont provincialism. Middle Devonian conodonts of eastern Australia appear to have close affinities with both North American and European forms.