Caestocorbula clarendonensis was another small corbulid clam of the London Clay soft-bottom community. It lived buried in the sediment and is interpreted as an infaunal suspension feeder, filtering food particles from seawater while protected beneath the seabed.

Although tiny compared with the larger London Clay bivalves, animals such as C. clarendonensis would have been important in processing suspended organic material and transferring it into the benthic food web. Their shells also record the diverse range of burrowing lifestyles supported by the warm early Eocene sea.