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Bright green daisy aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Adult apterae of Illinoia goldmaryae (see first picture below) are bright green and elongate oval. The antennal tubercles are well developed and moderately divergent, and the antennae are about 1.1-1.4 times as long as the body. Antennal segment III has 1-7 (usually 2 or 3) secondary rhinaria, extending in a row over about basal third. The longest hairs on segment III are very short at 0.17-0.23 times the basal diameter of that segment (cf. Macrosiphum euphorbiae, which has conspicuous hairs on segment III , the longest 0.5 times the basal diameter or more). The rostrum reaches just past the second pair of coxae (see clarified mount below), with the apical rostral segment 0.81-1.32 times as long as the second hind tarsal segment, and bearing 2 accessory hairs. The abdominal dorsum is smooth with 14-16 hairs on each of tergites I-VI. The legs are light brownish with the apices of the tibiae and the tarsi darker; the first tarsal segments are usually with 3 hairs. The siphunculi (see third picture below) are pale but dusky-tipped, 1.8-2.5 times as long as the cauda, clearly somewhat swollen proximal to the reticulated zone, with 4-5 rows of polygonal reticulations at apex, and a well developed apical flange (cf. Macrosiphum euphorbiae which usually has cylindrical siphunculi). The cauda is elongated, moderately blunt with 6 hairs. The body length of adult Illinoia goldmaryae apterae is 1.8-2.9 mm.
First image above copyright Andrew Jensen, second & third images above copyright Hwalran Choi,
The alate Illinoia goldmaryae (not pictured) is similar to the apterous morph, but has a dark head and thorax, and has dark marginal sclerites and smaller transverse pleural intersegmental sclerites on the abdomen. Antennal segment III bears 17-20 secondary rhinaria over almost the full length of the segment. The last rostral segment is as long as or a little longer than 2nd joint of hind tarsi. The apices of the siphunculi are slightly darker and are reticulated; the swollen area is about 1.1-1.4 times as wide as the widest diameter more basal.The cubital veins in fore wings are slightly bordered.
Illinoia goldmaryae feeds on the the young growth of various genera of Asteraceae, including asters (Aster), horseweeds (Conya), fleabanes (Erigeron) and goldenrods (Solidago). In their native North America, populations are usually monoecious holocyclic, with fundatrices on Solidago in April and males in September, although presumed anholocyclic populations are known where the species has been introduced to other countries. The species is widespread in USA and eastern Canada, Central America and some South American countries. Introduced populations have been reported in England, the Azores and Tunisia.
Other aphids on the same host
Illinoia goldmaryae has been recorded on 2 Conyza species (Conyza bonariensis, Conyza canadensis).
Illinoia goldmaryae has been recorded on 1 Erigeron species (Erigeron philadelphicus).