Results for 'Kosmoceras jason' (2 entries found)

Kosmoceras inner whorls are involute and the outer whorls becomes moderately evolute. The fine ribbing on the inner whorls tends to disappear on the body chamber. The ventral tubercles, separated by a smooth depression, disappear on the body chamber which presents a smooth venter. The periumbilical... [view details for full description]

Kosmoceras inner whorls are involute and the outer whorls becomes moderately evolute. The fine ribbing on the inner whorls persists on the body chamber and become wavy when approaching the aperture, announcing the lappets. The ventral tubercles, separated by a smooth depression also persists on the... [view details for full description]