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Aphidinae : Macrosiphini : Illinoia pepperi


Illinoia pepperi

Eastern blueberry aphid

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

Identification & Distribution

Adult apterae of Illinoia pepperi (see picture below of colony of immatures) are green or red, with rather dark antennae, legs and siphunculi. The antennae about 1.4-1.8 times as long as body, with 1-12 secondary rhinaria on the basal area of segment III. The longest hairs on antennal segment III are 0.2-0.6 times the basal diameter of that segment. The rostrum reaches to the second pair of coxae, with the apical rostral segment (RIV+V) 0.8-1.0 times the second hind tarsal segment (HTII) (cf. Illinoia azaleae and Illinoia borealis, where RIV+V are longer than HTII). The first tarsal segments have 3-5 hairs. The siphunculi are dark to black, sometimes paler at the extreme base, and are swollen up to about 1.1-1.3 times the basal diameter over the distal 0.33-0.38. The cauda is usually pale, but sometimes black, with a slight constriction, about half the length of the siphunculi, and bearing 3 pairs of lateral hairs and 1 dorso-apical hair. The body length of adult Illinoia pepperi apterae is 1.7-2.8 mm.

Copyright Jerry A. Payne, USDA Agricultural Research Service,,
under a Creative Commons License.

The alate Illinoia pepperi is similar to the apterous vivipara, but also has small brownish marginal sclerites and small pleural intersegmental sclerites. The antennae are brownish to black, with the base of segment III paler. They have 13-21 rhinaria on segment III, more-or-less in a row, extending from just above the pale base over nearly the whole length of the segment. The siphunculi are brownish to black with the apices sometimes paler.

Illinoia pepperi is monoecious on blueberry (Vaccinium spp.). Populations are holocyclic with oviparae and alate males in October. The species is restricted to north-eastern North America, where it is regarded as the major source of blueberry scorch virus (BIScV) affecting highbush blueberry production in the region.


Other aphids on the same host

Blackman & Eastop only recorded Illinoia pepperi on 2 Vaccinium species (Vaccinium macrocarpon, Vaccinium pennsylvanicum). However, Ranger et al. (2006) also noted its occurence on Vaccinium angustifolium & Vaccinium myrtilloides, and as a major virus-transmitting pest, on cultivated highbush blueberry (Vaccinium corymbosum). It was also recorded on Vaccinium stamineum (deerberry) by Jerry A. Payne (see picture above).


Damage and control

Because Illininoia pepperi is the most abundant aphid infesting cultivated highbush blueberries in the northeastern United States, it is viewed as the primary vector of blueberry scorch virus (BIScV) within this region (Ranger et al., 2006). BIScV has become one of the most economically important diseases affecting highbush blueberries on both the east and west coasts of the United States. It belongs to the carlavirus group and is transmitted in a nonpersistent manner. The primary tactic currently used for reducing the spread of BlScV in conventionally grown blueberries is the use of insecticides to control aphid vectors, mainly Illinoia pepperi in the northeast, along with removal of symptomatic plants.


We are grateful to Jerry A. Payne, USDA, for making his image of Illinoia pepperi available for use under a Creative Commons License.

We have used the species accounts given by MacGillivray, (1958) together with information from Ranger (2006) and from Roger Blackman & Victor Eastop in Aphids on Worlds Plants. We fully acknowledge these authors and those listed in the reference sections as the source for the (summarized) taxonomic information we have presented. Any errors in 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


  • MacGillivray, M.E. (1958). A study of the genus Masonaphis Hille Ris Lambers, 1939 (Homoptera: Aphididae). Temminckia 10: (p. 85).

  • Ranger, C.M. et al. (2006). Evaluation of Vaccinium spp. for Illinoia pepperi (Hemiptera: Aphididae) performance and phenolic content. Journal of Economic Entomology 99(4), 1474-1482. Full text