Gillette (3) described this species as Chermes similis in 1907. His description was of winged females from galls but he mentioned that wingless females and their egg clusters were also present in some galls, although there was no way to make certain that they were of the same species. The galls were on blue spruce from Colorado, and winged adults from these settled on spruce in cages. Patch (4) reported this species in 1909, on Norway, white, red, and black spruces from Maine. She found that the winged females settled 'on all these spruces but preferred white spruce. Wingless females with egg clusters were present in the galls and she assumed they were Chermes similis Gillette. Annand (1) placed the species in the genus Pineus, along with all species having four abdominal spiracles. He referred to the previous writers, and gave a description of a wingless adult, “probably from a gall”, included with Gillette's type material. He tentatively called this form a fundatrix. He also described a wingless female and a ‘nymph’ which Patch had found associated with galls of P. similis, as Pineus sp.