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Brachycorynella aphidsOn this page: Genus Brachycorynella asparagi
Brachycorynella are rather small wax-coated aphids, similar in appearance and characteristics to Brachycolus. However, both the antennae and terminal process are much shorter. Also, they feed on asparagus (Asparagus spp.), and not Caryophyllaceae. The siphunculi are extremely short, and sited behind the border between abdominal segments V & VI, as in Diuraphis.
Brachycorynella aphids are endemic to Eastern Europe, but have spread naturally, or been introduced, to other parts of Europe and Asia, and to North America.
Brachycorynella asparagi (European asparagus aphid) Europe, North Africa, Asia, North America
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.