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Spot-winged raspberry aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Adult apterae of Illinoia rubicola are pale greenish-yellow, usually with a broad dark green spinal stripe and dark green abdominal margins. The antennal terminal process is 5.5-8.2 times as long as the base of antennal segment VI (cf. Illinoia maxima, which has the terminal process 4.5-6.2 times the base of segment VI). The third antennal segment bears 7-22 secondary rhinaria (cf. Illinoia davidsoni in which antennal segment III bears 20-23 secondary rhinaria). The apical rostral segment (RIV+V) is 1.4-1.85 times as long as the second hind tarsal segment (HTII) (cf. Illinoia davidsoni, which has RIV+V 1.9-2.2 times the length of HTII). There are well developed marginal tubercles present on all of abdominal tergites I-VII, and spinal tubercles usually on tergites VII-VIII (cf. Illinoia maxima, which usually has marginal tubercles only on tergites II-V, and no spinal tubercles). The siphunculi are light brown with darker tips and a sub-apical zone of polygonal reticulation distal to a swollen part (cf. various Macrosiphum and Sitobion species, which have their siphunculi tapering or cylindrical). The body length of adult Illinoia rubicola apterae is 3.1-4.6 mm.
Images above by permission, copyright Claude Pilon, all rights reserved.
Alatae of Illinoia rubicola (see second picture above) have a dark pterostigma and a large black spot at the tip of each forewing (cf. the alate Illinoia davidsoni, which has no black spot at the tip of each forewing). Immatures (see left-most aphid in picture below) have somewhat shorter and less swollen siphunculi, but otherwise resemble the adult apterae.
Image above by permission, copyright Claude Pilon, all rights reserved.
The spot-winged raspberry aphid can be found on stems of American red raspberry (Rubus strigosus, and on a few other closely-related Rubus spp. Winter (1929) notes that Illinoia rubicola (referred to as Amphorophora rubicola) is markedly gregarious, and strong colonies are often found on the undersides of the leaves and on the canes near the tip of new growth. It does not host alternate and produces oviparae and alate males in October, overwintering as eggs on raspberry. It is a vector of black raspberry necrosis virus (BRNV), but not of raspberry leaf curl. BRNV causes mild leaf mottle. Illinoia rubicola is widely distributed in the United States and Canada.
Other aphids on the same host
Illinoia rubicola has been recorded on 3 Rubus (Rubus idaeus var. melanolasius, Rubus strigosus, Rubus villosus var. frondosus).