Abstract
Three distinct spp. of Belemnopsis are present in the Heterian stratotype. B. annae sp. nov. and B. maccrawi sp. nov., are described and the description of B. keari Stevens, is emended. B. annae is of lower Heterian age. B. maccrawi and B. keari appear in the upper Heterian and their zones are partially overlapping. A 4th ill-defined population consisting of a heterogeneous assortment of several taxa is present in the middle Heterian. The 3 named species are present in restricted sets of beds and because their zones apparently represent short time intervals, they are expected to be of stratigraphic value.

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