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The Upper Pliocene Hopegate Formation of north central Jamaica is a dolomitized raised reef. Hitherto, its palaeontology has been largely ignored because of the poor preservation; the Hopegate Formation is highly karstified, well indurated and fossils are commonly preserved as molds. However, moldic preservation has enhanced the common borings. Ichnotaxa identified from this formation include Entobia ovula? Bromley and d'Alessandro; Entobia ispp.; Gastrochaenolites isp. cf. G. torpedo Kelly and Bromley; Gastrochaenolites pickerilli Donovan; Gastrochaenolites ispp.; Oichnus simplex Bromley; Rogerella isp. cf. R. lecontrei Saint-Seine; Talpina isp. cf. T. hirsuta Voigt and Uniglobites flomerata (Morris). There are more specimens of Entobia than all other ichnotaxa combined. Comparison with other Neogene formations or members in the Antilles demonstrates that the association Entobia + Gastrochaenolites + Oichnus is near-ubiquitous. Caulostrepsis Clarke, which is common in modern shallow water environments in association with Entobia and Gastrochaenolites, is less common in the ancient associations of the Antilles. [ABSTRACT FROM AUTHOR]

Pleistocene brachiopods are poorly known from the Antillean region, but are locally common in fore-reef deposits of Jamaica (lower Pleistocene Manchioneal Formation) and Barbados (Coral Rock). Of the four species known, two are new. Lacazella sp. cf. L. caribbeanensis Cooper, an encrusting thecideidean, is known from only three valves. Other species are terebratulides. Tichosina inconstanta sp. nov. is a large, ventribiconvex Tichosina species of elongate oval to tear-drop shaped outline, variably uniplicate with a pedicle foramen of moderate diameter. It differs from the similar Tichosina? bartletti (Dall) in having a larger pedicle foramen and a less-marked plication. Argyrotheca barrettiana (Davidson) is a medium to large, usually transverse Argyrotheca species, multicostellate with usually eight costae and costellae, increasing by intercalation up to 21 on the largest shell. The species was originally described from the Recent of the Caribbean. Terebratulina manchionealensis sp. nov. is a small, elongately oval to subtriangular Terebratulina species with a ventral sulcus and subcarinate dorsal valve. Usually there are 6-8 ribs per 2 mm at 5 mm growth stage. The known diversity in Pleistocene brachiopods from the Antilles, only four species, is depauperate when compared to the 50+ species known from the Recent of the Caribbean Sea and the Straits of Florida. The Pliocene fauna of the region, however, is similarly lacking in diversity, but includes the same genera. The comparable Pleistocene fauna of the Mediterranean Sea includes eight species belonging to six genera, including Lacazella, Argyrotheca and Terebratulina; the Mediterranean Gryphus is an analogue for the Caribbean Tichosina. [ABSTRACT FROM AUTHOR]

As part of a review of its distribution within the Antillean region, well-preserved casts of the boring Gastrochaenolites Leymerie are described from the Neogene Seroe Domi Formation of Aruba, Bonaire and, particularly, Curaçao (ABC Islands), Netherlands Antilles; G. ampullatus Kelly and Bromley, G. torpedo Kelly and Bromley, and G. turbinatus Kelly and Bromley. These trace fossils were originally classified as bivalves, namely Spengleria rostrata? (Spengler), Lithophaga spp. and Rocellaria sp., specimens of which are preserved in at least some of the casts. This is the first record of G. ampullatus from the Antillean region; casts of both siphonal canals are retained by some specimens, making their preservation superior to that of the holotype. Gastrochaenolites turbinatus is also rare in the Antillean region; the specimens from the ABC Islands preserve distinctive concentric grooves on their necks, produced by the borer and indicating the former position of the neck-to-chamber transition. Each Gastrochaenolites ichnospecies is bored by a different bivalve. This study, based on one of the most diverse collections of Gastrochaenolites known from the Antillean region, extend its known diversity and geographic distribution; only the Upper Oligocene of Jamaica shows a greater diversity. [ABSTRACT FROM AUTHOR]

Diversity of Pleistocene marine invertebrates with single component, robust, easily identifiable skeletons shows a good correspondence to that of the Recent when compared between similar environments in the same region. Such comparisons are less easily made for multi-element skeletons. In the Antilles there are 24 extant species of echinoids in 0-30 m water depth. Considering all available fossils - complete tests, disarticulated spines, and test fragments and ossicles - the Pleistocene echinoids of the Antillean region have a high similarity with the extant shallow water fauna ( c . 63% specific and 72% generic similarity). Many of the extant, shallow water, regular echinoid taxa are known from the Pleistocene, although irregular echinoids are less well represented. These results are comparable with those determined for coeval benthic invertebrates from this and other geographic regions, and indicate a high degree of similarity from a survey which is so far limited to only a few of the islands. Not all Pleistocene units considered herein were deposited in shallow water, but they include autochthonous specimens of taxa whose depth range extends beyond shallow water at the present day or presumed allochthonous specimens derived by downslope transport from shallower water, or both. [ABSTRACT FROM AUTHOR]

Examines the evolution of echinoderm stalked crinoids in the Caribbean. Fossil record; Comparison of the fossil crinoids from the Lower to Middle Miocene of the Antiles with those found in older or younger deposits; Electron micrographs of fossil isocrinid crinoid ossicles.