Extensive Free-Swimming Comaturella Crinoid Death Assemblage

Description: This is an exquisitely-preserved example of a death assemblage of SEVENTEEN free-swimming, stemless crinoids from the Cretaceous Sublithographic Limestone of Haqel, Lebanon, known as Comaturella. The genus has been called Pterocoma , but that genus is preoccupied by a genus of insects established in 1834. The elongated pinnules seem to be an adaptation to a low current environment. The long pinnules would be better able to filter out the limited food supplies, giving this crinoid an advantage over others. The genus was quite long-lived in that it was found in the Jurassic deposits of Solnhofen, Germany some 55 million years earlier. There are two small negative examples of the Ophiuroid Geocoma libanotica found in the lower left of the plaque. Examples of crinoids from the Cenomanian (95 million year old) deposits of Lebanon are not readily available, and few are ever seen as extensive as this one. When one considers that a SINGLE example typically sells well in excess of $200, this plaque is a bargain!