Biology, images, analysis, design...
Aphids Find them How to ID AphidBlog
"It has long been an axiom of mine that the little things are infinitely the most important" (Sherlock Holmes)



Pineus pini

Pine woolly aphid, Scots pine adelgid

On this page: Identification & Distribution  Other aphids on the same host 

Identification & Distribution:

The apterous female (known as the 'sistens') of Pineus pini is dark brown to dark red, almost spherical and covered in white wax wool. The head and prothorax are heavily chitinized. The antennae are 3-segmented. The abdomen has four distinct pairs of spiracles and an ovipositor. The body length of the wingless form is 1.0-1.2 mm.

The winged female is mainly reddish grey with 5-segmented antennae. The forewings are hyaline and the veins are tinged with red. The body length of the Pineus pini winged form is 1.0 -1.2 mm.

The pine woolly aphid has lost host alternation and sexual reproduction and remains all year on pine (Pinus sylvestris and Pinus mugo). There is an overwintering generation on the twigs and two or more overlapping generations attacking the current year's shoots. Pineus pini eggs are laid in abundant wax-wool. The second of the summer generations in May-June includes winged forms which disperse to other pine trees. Young seedling pines are commonly infected by first-instar crawlers dispersed by wind.


Other aphids on same host:

Blackman & Eastop list about 170 species of aphids  as feeding on pines worldwide, and provides formal identification keys for aphids on Pinus.


We have made provisional identifications from high resolution photos of living specimens, along with host plant identity. In the great majority of cases, identifications have been confirmed by microscopic examination of preserved specimens. We have used the keys and species accounts of Blackman & Eastop (1994)  and Blackman & Eastop (2006)  supplemented with Blackman (1974) , Stroyan (1977) , Stroyan (1984) , Blackman & Eastop (1984) , Heie (1980-1995) , Dixon & Thieme (2007)  and Blackman (2010) . We fully acknowledge these authors as the source for the (summarized) taxonomic information we have presented. Any errors in identification or 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).

Useful weblinks