The extant irregular echinoids Echinoneus cyclostomus Leske and Brissus unicolor (Leske) are reported from the middle Pleistocene of Barbados. The moderately robust E. cyclostomus is well-preserved, while B. unicolor, which had a thin test in life, occurs as an internal mold. The holectypoid E. cyclostomus sensu lato occurs in fossiliferous deposits of Upper Oligocene to Pleistocene age in the Antillean region, showing remarkably little overall variation in test shape during this period. Similarly, gross morphological features of Recent B. unicolor are not dissimilar to those seen in some Caribbean species from the Paleogene, such as B. sp. cf. B. unicolor from the Middle Eocene of Jamaica. Superior fossil specimens will be required to determine if certain fossil species within these genera are valid. This analysis supports the observation that many taxa of the modern Antillean, shallow-water echinoid fauna have essentially persisted within the region since at least the Oligocene.
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