Rock, G.C., & McClain, D.C. 1990 Effects of constant photoperiods and temperatures on the hibernating life stages of the San Jose Scale (Homoptera: Diaspididae) in North Carolina.. Journal of Entomological Science 25(4): 615-621.

Notes: Abstract: The black cap phase of the first instar nymph accounted for about 85% of the hibernating life stages of Quadraspidiotus perniciosus in an apple orchard; this species hybernates in a nondiapause state of dormancy; dormancy is temperature dependent. Keywords: biology.