Polavarapu, S., Davidson, J.A., & Miller, D.R. 2000 Life history of the putnam scale, Diaspidiotus ancylus (putnam) (Hemiptera: Coccoidea: Diaspididae) on blueberries (Vaccinium corymbosum, Ericaceae) in New Jersey, with a world list of scale insects on blueberries.. Proceedings of the Entomological Society of Washington 102(3): 549-560.

Notes: Life history of the Putnam scale was investigated during 1997 and 1998 on highbush blueberries in the pine barrens of southern New Jersey. Putnam scale has two generations each year. Crawler emergences in the first and second generations peaked during late May and early to mid-August, respectively. This species overwinters as second instar nymphs, primarily under the bark (cork cambium) of the host. Adult females that occur on or under the bark of blueberries differ morphologically from those on the leaves and fruit. Descriptions of both forms are provided. Nine species of parasitoids were reared from canes containing Putnam scale infestations and peak emergence times of the parasitoids coincided with the transition between the adult females and crawlers.