Barth’s myochordotonal organs (Barth’s MCO) Barth’s myochordotonal organs (Barth’s MCO)thin-walled sensory organ found in the exoskeleton on each leg of semi-terrestrial ocypodid crabs. Related Articles: How do marine invertebrates detect sounds?Tutorial: Can Animals Sense These Sounds Part II Chris Knowlton2017-02-26T20:10:08-05:00