An unusual crinoid-coral association from the Lower Carboniferous of Clitheroe, Lancashire

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Abstract
SUMMARY: A well-preserved calyx of the monobathrid camerate crinoid Amphoracrinus gilbertsoni (Phillips) from the Lower Carboniferous (Chadian, Viséan) of Salthill Quarry, Clitheroe, Lancashire, is preserved in close association with a solitary rugose coral. Evidence for the coral being an epizoozoan on the crinoid includes its perpendicular orientation to the calyx, its position at the base of a free arm (B ray) in the AB interray, breakage of the crinoid plates around the coral (calyx ligamentation had not rotted post-mortem), and a growth deformity in the AB interray. The position of the coral indicates that, in life, it was elevated above the sea floor and directed into the prevalent water current by the crinoid. Its position, adjacent to a free arm and growth deformity of the AB interray suggest it was also a parasite on the adoral groove of the crinoid arm.