Observations on macroborings from the White Limestone Group of Jamaica

The Middle Eocene to Middle Miocene White Limestone Group contains uncommon, but relatively diverse, macroborings along with moderately diverse, poor to moderately preserved, soft-sediment ichnotaxa. The Troy, Somerset, Moneague and Montpelier fomations have yielded macroborings. Nine ichnogenera represented by twenty-nine ichnospecies are identified. These are Caulostrepsis taeniola Clarke, Clionolithes irregularis Fenton & Fenton, Cl. radicans Clarke, Conchotrema canna Price, Co. tenuis Teichert, Conchotrema isp., Entobia cateniformis Bromley & d’Alessandro, E. gigantea Bromley & d’Alessandro, E. megastoma (Fischer), E. ovula Bromley & d’Alessandro, E. paradoxa (Fischer), Entobia ispp. AA, AB, AC, AD, Gastrochaenolites anauchen Wilson & Palmer, G. cluniformis Kelly & Bromley, G. dijugus Kelly & Bromley, G. lapidicus Kelly & Bromley, G. torpedo Kelly & Bromley, Gastrochaenolites isp., Maeandropolydora crassa Bromley & d’Alessandro, M. decipiens Voigt, M. elegans Bromley & d’Alessandro, M. sulcans Voigt, Oichnus simplex Bromley, O. paraboloides Bromley, Trypanites isp. and Uniglobites glomerata (Morris). Most of these structures are preserved in scleractinian corals.

Only E. megastoma (preserved in carapaces) and E. ovula (preserved in molluscs) show affinities for a specific host. Trypanites isp. is also preserved in hardgrounds. The distribution of bioerosional structures reflects, at least in part, the taphonomic history of the bored substrates. The fossiliferous Moneague and Montpelier formations exhibit the highest diversity of these structures.