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Uroleucon erigeronenseLarge fleabane daisy aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same hostIdentification & DistributionAdult apterae of Uroleucon erigeronense are uniformly pale green or yellowish green, usually with a darker spinal stripe (see first two pictures below, from USA and Serbia respectively). The antennae are dark except for antennal segments I & II, which are pale. The terminal process is 3.1-4.7 times the length of the base of antennal segment VI. The apical rostral segment (RIV+V) is 0.9-1.1 times as long as the second hind tarsal segment (HTII). The dorsum is membranous, and the body hairs are not placed on scleroites. The siphunculi are mainly dark but have a pale basal section and are 1.8-2.4 times the length of the cauda. The cauda is pale or dusky and has 6-10 hairs, the most distal of which are shorter than the more proximal hairs. The body length of adult Uroleucon erigeronense apterae is 2.3-2.8 mm.
First and third images above copyright Andy Jensen under a Attribution-NoDerivs-NonCommercial 1.0 Generic license The alate Uroleucon erigeronense (see third picture above) is green, like the aptera, and has an unmarked dorsum and a dusky cauda. The ovipara is similar to the apterous viviparous female, but has dorsal hairs placed on distinct but unpigmented scleroites and the basal half of the hind tibia is dark and swollen. The alate male has the anterior membranous parts of the body reddish brown, and the abdomen green.
Micrographs of clarified mounts by permission of Roger Blackman, copyright AWP all rights reserved. The 'typical' hosts of Uroleucon erigeronense are fleabane daisies (Erigeron and Conyza, but not Pulicaria, fleabane) where it feeds on the upper parts of the stems. In its native North America Uroleucon erigeronense is also found on several other genera in the Asteraceae, as it is in Central and South America where it is invasive. It has also been introduced to Europe where it is restricted to fleabanes, from where it has spread to most of the western Palaearctic as well as Korea and Australia. In northern temperate climates Uroleucon erigeronense produces oviparae and alate males in September-October. Biology & EcologyJensen et al. (2010) describe the morphology and biology of Uroleucon erigeronense and provide an updated list of hosts in the USA, along with the results of host plant transfer experiments. Brumley & Watson (2016) provide the first records of Uroleucon erigeronense on Conyza from Australia, along with biological and morphological information. Other aphids on the same host
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