Caenestheriella gynecia, a poorly known species of the clam shrimp family Cyzicidae, is reported from New England for the first time. Two populations were monitored, along with water chemistry and vegetation features, in wooded ephemeral pools along abandoned roads in Berkshire County, Massachusetts from August through September, 2000. All animals collected alive and over 6 mm in length contained eggs. No male features were detected in any specimens. Field and laboratory observations revealed no copulation among individuals. All specimens conformed to the original description but demonstrated variability that extended across two recognized genera, Cyzicus and Caenestheriella.