Identification & Distribution
Adult apterae of Cinara pulverulens are yellowish brown, with a pair of longitudinal rows of black patches vanishing about middle of abdomen; also two median rows of black dots. They are heavily waxed throughout, except on black areas, or immediately after a moult (cf. Cinara wahhaka, which are shining dark brown without wax). The antennae are pale yellow, except for segments I, II and VI which are black. The femora are yellow with the distal part black, the tibiae are yellow with black tips, and the tarsi are black. Body hairs are fine and rather numerous; the hairs on the hind tibia are moderately long (0.08-0.10 mm), equalling or slightly exceeding the diameter of the tibiae (cf. Cinara juniperivora, which has the hairs on the hind tibia mostly less than diameter of tibia at midpoint) The siphuncular cones are black and quite small, with a diameter at the base of the cone of 0.15 mm (cf. Cinara rubicunda in Oregon, which has large siphuncular cones with a maximum basal diameter of more than 0.3 mm).
Note: Blackman & Eastop in Aphids on Worlds Plants suggested that Cinara pulverulens may be synonymous with Cinara burrilli. However, this is not at all certain given the colour difference (black with pruinose patches for Cinara burrilli). According to the Cinara key in Palmer (1952), Cinara pulverulens can be separated from Cinara burrilli by the length of its second hind tarsal segment. Unfortunately in the text, Palmer gives this length as 0.22 mm for Cinara pulverulens compared to 0.20-0.23 mm for Cinara burrilli.
Image above copyright Whitney Cranshaw under a Creative Commons Attribution 3.0 license.
The alate Cinara pulverulens has the head and thorax dark brown, but otherwise the same colour as with the apterous vivipara. The fore wing has the media vein twice-branched. The length of the hairs hind tibia are barely twice the diameter of that tibia.
Cinara pulverulens is monoecious holocyclic on the Rocky Mountain juniper (Juniperus scopulorum) and the Utah juniper (Juniperus osteosperma = Juniperus utahensis). It feeds on the bark of small twigs. Oviparae and alate males occur in September-October. The powdery juniper aphid is found in several states in the western USA (Colorado, Idaho, Utah, & New Mexico).
Other aphids on the same host
Cinara pulverulens has been recorded from 2 juniper species (Juniperus osteosperma, Juniperus scopulorum).
Acknowledgements
We are grateful to Whitney Cranshaw for making his image of Cinara pulverulens available for use under a creative commons licence.
We have used the species account given by Gillette & Palmer (1924) (as Lachnus pulverulens) and Palmer (1952) together with information from Roger Blackman & Victor Eastop in Aphids on Worlds Plants. We fully acknowledge these authors and those listed in the reference sections as the source for the (summarized) taxonomic information we have presented. Any errors in information are ours alone, and we would be very grateful for any corrections. For assistance on the terms used for aphid morphology we suggest the figure provided by Blackman & Eastop (2006).
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References
- Gillette, C.,P. & Palmer, M.A. (1924). New Colorado Lachnini. Annals of the Entomological Society of America 17, 1-44.
- Palmer, M.A. (1952). Aphids of the Rocky Mountain Region: including primarily Colorado and Utah, but also bordering area composed of southern Wyoming, southeastern Idaho and northern New Mexico. Thomas Say Foundation, Denver. Full text
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