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"It has long been an axiom of mine that the little things are infinitely the most important" |
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Aphis spiraephilaBrown spirea aphidOn this page: Identification & Distribution Biology & Ecology Ant attendance Other aphids on the same hostIdentification & DistributionAdult apterae of Aphis spiraephila vary in colour from hazel to chestnut-brown. They are coated with powdery white wax. (Note their original description by Patch describes these aphids as "huckleberry black with a slight white bloom of wax powder"). The head, siphunculi and cauda are dusky or dark, but their antennae and legs are mainly pale. The antennal terminal process is 1.3-1.5 times the length of the base of antennal segment VI. Abdominal tergites I and VII bear marginal tubercles. The siphunculi are quite short, only 0.4-0.5 times as lomg as the cauda (c.f. Aphis spiraecola, which has siphunculi more than 0.6 times the caudal length). The cauda bears 13-16 hairs. The body length of adult Aphis spiraephila apterae is 1.3-1.7 mm.
Both images above by permission, copyright Claude Pilon, all rights reserved. Aphis spiraephila alatae have a black head and thorax, but are otherwise coloured much like the apterae. Their siphunculi are cylindrical or slightly tapering without a distinct flange and sometimes slightly curved inwards. The cauda is elongate, spoon-shaped and bears 3-4 lateral and 3-4 dorso-lateral hairs on each side. Immatures also resemble the adults in general appearance. Image above by permission, copyright Claude Pilon, all rights reserved. Aphis spiraephila is found on the terminal shoots, leaves and twigs of meadowsweet (Spiraea species). They do not host alternate, but remain all year on meadowsweet. The brown spirea aphid is usually ant-attended. Sexual forms develop in autumn, with oviparae having been found in October. Oviparae are more spindle-shaped than the apterous viviparae, with pale hind tibiae that are hardly swollen and bear scattered rather large sensoria, mostly on the proximal half. Males are so far undescribed. Aphis spiraephila is a widespread North American species; records elsewhere (Ukraine & East Asia) are probably erroneous. Biology & EcologyAnt attendanceGuyton (1924-1926) recorded Aphis spiraephila being attended by the ant Formica fusca var subsericea in Pennsylvania, USA. McPhee et al. (2012) conducted surveys of Homoptera in sites infested and uninfested with the invasive ant Myrmica rubra in Maine, USA. They also conducted manipulative experiments to quantify the effects of Myrmica rubra on homopteran abundance and composition. In both surveys and experiments they specifically looked at the impact of Myrmica rubra on Aphis spiraephila populations on white meadowsweet (Spiraea alba), a native herbaceous plant species common in both ant-infested and uninfested sites.
Other aphids on the same hostAphis spiraephila has been recorded on 4 species of the Spiraea genus : (Spiraea alba var latifolia, Spiraea betulifolia, Spiraea douglasii, Spiraea elegans).
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