Abstract
A row of oval unpaired, ventral body attachment scars, accompanied by pseudosutures and drag bands, is preserved on surfaces of steinkerns of a lower Chesterian (Mississippian) goniatitid ammonoid, Goniatites multiliratus, from Oklahoma. Many smaller oval and crescentic attachment scars are present in the interspaces between these ventral attachment scars and between pseudosutures. Comparison with the muscle scars of other extant and fossil shelled cephalopods suggests that the unpaired ventral scars of this species represent the attachment sites of the muscle or ligament at the posterior end of the body. The smaller oval and crescentic scars on the ventral and lateral sides of each chamber appear to indicate weaker and less permanent attachments of muscular tissue to the shell wall. These are presumed to have been formed during gradual forward movement of the body.
