ABSTRACT: We herein describe a new family, the Ammolagenidae, and emend the description of the genus Ammolagena Eimer and Fickert, 1899 based on a study of paralectotypes of the type species Ammolagena clavata (Jones and Parker 1860) in the Natural History Museum, London. The genus Ammolagena possesses a second aperture that opens out of the proloculus opposite the tubular chamber. Because no other genus belonging to the Suborder Ammodiscina possesses a second opening, and in the absence of any regular mode of coiling, we remove the genus Ammolagena from the Ammodiscina, and place it in the new family Ammolagenidae within the Suborder Hormosinina, Superfamily Hormosinellacea.