Types. A. Holotype of Volvulella micratracta, H 1.5 mm, ANSP IP3842. B. Syntype of Volvulella minutissima new comb., H 2.3 mm, ANSP IP13267. C–D. Holotype of Volvulella ornata, H 3.2 mm, ANSP IP3178. E. Holotype of Volvulella parallela, H 2.1 mm, ANSP IP3188. F. Holotype of Volvulella tritica, H 4.1 mm, ANSP IP19104. G. Holotype of Atys cinctorii, H 2.6 mm, ANSP IP3185. H. Syntype of Atys sulculorum, H 2.5 mm, ANSP IP3317. I–J. Syntype of Cylichna cylindrus, H 4.7 mm, ANSP IP1554. K. Syntype of Cylichna dekayi, H 5.0 mm, ANSP IP6008. L. Syntype of Cylichna kellogii, H 5.7 mm, ANSP IP13266. M. Holotype of Cylichna recta, H 8.0 mm, ANSP IP18782. N. Syntype of Bulla occidentalis, H 10.0 mm, ANSP IP17139. O–P. Lectotype of Cylichna costata, H 16.0 mm, ANSP IP4338. Q–R. Syntype of Acteon sculptus, H 1.9 mm, ANSP IP1515. S. Syntype of Acteon milium, H 2.1 mm, ANSP IP1520. T. Holotype of Acteon angulatus, H 2.4 mm, ANSP IP1521.