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European asparagus aphidOn this page: Identification & Distribution Other aphids on the same host Damage & Control
Identification & Distribution
Adult apterae of Brachycorynella asparagi (see two pictures below) have a slender body and rather short appendages. They are coloured green and covered with grey mealy wax. The antennae are about 0.3 times body length, with the terminal process about 0.9-1.5 times the base of antennal segment VI. The apical rostral segment is about 0.6 times the second hind tarsal segment. The abdominal dorsum is reticulate, and body hairs are short. The siphunculi, which are barely visible in the pictures below, are very small truncated cones, only about 0.1-0.2 times the caudal length (cf. polyphagous species on asparagus e.g. Macrosiphum euphorbiae, Macrosiphum pallidum, Myzus ascalonicus, Myzus ornatus, and Myzus persicae, which all have siphunculi longer than the cauda). The cauda is elongate, and has 3-4 pairs of lateral hairs and 1 preapical hair. There is no supracaudal process. The body length of adult Brachycorynella asparagi apterae is 1.2-1.8 mm.
First image above by permission, copyright Ivan Pančić, all rights reserved;
The alate Brachycorynella asparagi has relatively longer antennae than the aptera, about 0.6 times the body length. Antennal segment III bears about 5-10 secondary rhinaria, varying in sized - with the smallest half the size of the largest. The siphunculi are short and truncate.
Brachycorynella asparagi is monoecious on asparagus (Asparagaceae). The species is holocyclic, with alate males and oviparae developing in autumn. The European asparagus aphid can be a severe pest of garden asparagus (Asparagus officinale, see below), but is common on other species in the genus Asparagus. The European asparagus aphid is found in much of Europe, North Africa, south-west and Central Asia and China, and has been introduced into North America, where it is established in the temperate parts.
Other aphids on the same host
Brachycorynella asparagi has been recorded on 8 asparagus species (Asparagus aethiopicus var sprengeri, Asparagus brachyphyllus, Asparagus neglectus, Asparagus officinalis, Asparagus orientalis, Asparagus persicus, Asparagus setaceus, Asparagus tenuifolius).
Damage and control
Brachycorynella asparagi is a serious pest of asparagus. Feeding of the aphid causes a characteristic distortion of the terminal bud termed 'rosetting' (=witches brooms) of asparagus, with the internodes being shortened and the leaves being both shortened and turned blue green. Strong aphid infestation can cause dieback of seedlings. Affected stems of mature plants develop imperfectly, become stunted and broom-like, with plants growing in the shape of a bush.
First image above copyright Whitney Cranshaw, Colorado State Univ., Bugwood.
Second image copyright Rasbak, via Wikimedia Commons.
In the first picture above there is rosetting on the lower part of the asparagus plants, indicating presence of the asparagus aphid. The second picture shows normal growth.