Commensalism of new serpulid worm from the Hamilton Group (Middle Devonian) of New York

Abstract

A new serpulid worm, Filogranites booiji Cameron gen. et sp. nov., from the Cardiff Shale Member of the Marcellus Formation occurs as a cluster of individuals packed into polychaete worm shell-borings. The worms are represented by steinkerns of the straight to gently curved tubes that have been dissolved away. These serpulids seem to have clustered together in only vacated worm borings in the shells of only one species of clam. Because they filled the borings, no commensal relationship is indicated with the shell-boring polychaete. If the clams had been alive, the serpulids might have benefited from their feeding currents because the occupied borings are oriented perpendicular to and line up along the clam's gaping margins. Therefore, these serpulid worms may have been specifically selective for vacated polychaete borings in these clams with which theylived commensall