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Globose pine aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host Damage & Control
Identification & Distribution
Adult apterae of Cinara pergandei are large, globose, brown aphids, often shiny with a bronze lustre. They may or may not have wax powder, possibly dependent on whether they are ant-attended or not. Those shown here were not ant-attended, and were quite heavily dusted with wax powder (see first two pictures below). Most authors describe them as lacking any dorsal wax. Their eyes are on short lateral projections of the head, usually without any evident ocular tubercle. The hairs on antennal segment III are erect & long, 2.5-3 times the basal diameter of the segment. The dorsum is finely spotted with black (best seen in the clarified mount, third picture below). These spots are black scleroites at the base of many of the hairs, and are irregular and of varying size (cf. Cinara pinivora which usually has a large pair of dark sclerites or diffuse dusky areas on each tergite bearing several hairs). Abdominal tergite V has 50-110 hairs between the siphuncular bases, most of which are on small scleroites (cf. Cinara pinea, in which tergite V has 28-49 hairs between the siphuncular bases, most of them on large scleroites). The tibiae are rather uniformly dark, sometimes slightly less so near base (cf. Cinara pinea in which all the tibiae have a pale section on the basal half). The siphuncular cones are black. The body length of an adult Cinara pergandei aptera is 3.0-4.4 mm.
The alate Cinara pergandei (not shown) has lateral extensions on its head bearing the eyes, the posterior margin of those extensions being almost as great as the diameter of the eyes.
Cinara pergandei live on the twigs and new growth of all pine species in subsection Contortae (e.g. the lodgepole pine, Pinus contorta) and on some of the southern yellow pines in subsection Australes (e.g. the jack pine, Pinus banksiana) in eastern North America, but it does not feed on other western North American pines. Oviparae and alate males can be found in September to November. Cinara pergandei is found in the eastern USA, across Canada and in Cuba.
Biology & Ecology
Cinara pergandei is very much a solitary species, with adults scattered over the trees. In spring the fundatrices are sometimes found in company with nymphs, but in the later generations the females usually move away from their nymphs immediately after they are deposited. Only the immatures remain in small groups (see picture below).
Image above by permission, copyright Claude Pilon, all rights reserved.
Adult Cinara pergandei make quick, spider-like movements among the pine shoots. Few alate females are produced, and the aphids live on the same trees throughout the year. Oviparae with no pericaudal wax ring develop in the autumn along with alate males. After mating, the oviparae lay large, ovoid, black eggs, with each being attached singly half-way along a needle.
Cinara pergandei are sometimes not attended by ants, in which case the aphids develop a dense coating of wax powder. More often they are attended by carpenter ants (Camponotus herculeanus or Camponotus atriceps = Camponotus abdominalis) or formica ants (Formica subaenescens = Formica fusca) (Tissot, 1939; Bradley,1961). The picture below shows a Formica subaenescens.
Image copyright Arthur Scott Macmillan under a Creative Commons License.
Parasitoids reared from Cinara pergandei include Aphidius bicolor, Aphidius gillettei, Aphidius procephali and Euneura lachni (Tissot, 1939; Bradley,1961). Parasitized individuals always move out on a needle prior to mummification.
Other aphids on the same host
Cinara pergandei has been recorded from at least 12 Pinus species, all but one of which (Pinus strobus in subgenus Strobus, section Quinquefoliae, subsection Strobus) are in 3 subsections of the Pinus subgenus (subsections Australes, Contortae, and Pinus).
Damage and control
We can find no reference to Cinara pergandei causing damage to pine trees.