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Mangold AphidOn this page: Identification & Distribution Other aphids on the same host Damage & Control
Identification & Distribution
Adult apterae of Rhopalosiphoninus staphyleae on their primary host (Staphylea) are pear shaped, yellowish-white or pale yellow, with a translucent whitish spot on the anterior part of the dorsal abdomen (see pictures below). But note that apterae on the secondary host, and also in populations remaining through summer on the primary host (not pictured), are much more pigmented - being coloured dark olive green or brownish with very dark green or black dorsal markings. The antennal tubercles are rather well developed, with inner margins about parallel, but the median frontal tubercle is very little developed. The antennae are about the same length as, or slightly shorter than, the body, mostly pale, but with the apex of segment V and the whole of segment VI dark; the terminal process is 3.75-4.55 times as long as the base of antennal segment VI. Antennal segment III has 1-7 secondary rhinaria (cf. Rhopalosiphoninus latysiphon, where segment III has none). Antennal hairs are very short. The apical rostral segment is about as long as the second segment of the hind tarsus. The siphunculi are swollen, very pale with only the tip dusky or dark, and with a well developed flange. The swollen part is no more than 3.2 times thicker than the narrowest part of the stem (cf. Rhopalosiphoninus latysiphon, which has the swollen part 3.7-4.8 times thicker than the narrowest part). The siphunculi are 2.5-3.0 times the length of the cauda - which is pale, triangular with a very blunt apex and usually bearing 5 hairs. The body length of adult Rhopalosiphoninus staphyleae apterae is usually given as 1.5-2.3 mm (but in Aphids on Worlds Plants it is 2.3-3.0 mm).
Images above copyright Zoran Gavrilovic, all rights reserved.
The primary host of Rhopalosiphoninus staphyleae s. str. is bladdernuts (Staphylea spp.). Feeding by the aphid causes the leaves to curl and become mottled pale yellow. The aphid can be holocyclic in Europe, host alternating from late May onwards to its secondary hosts in the Liliaceae and Iridaceae (Tulipa, Hemerocallis, Crocus, Anthericum), and sometimes to the roots of plants (herbs, trees, grasses) in several other families. However, anholocyclic populations on the secondary hosts are also common, being found in Europe and North America, as well as Kenya, South Africa, Australia and New Zealand. The subspecies known as Rhopalosiphoninus staphyleae tulipaellus is found in Europe (and possibly America). Rhopalosiphoninus staphyleae tulipaellus is entirely anholocyclic on roots, especially on beets in store, giving it the common name of mangold aphid. Its status is unclear, but some authorities consider it a good species.
Other aphids on the same host
Rhopalosiphoninus staphyleae has been recorded from 2 Staphylea species, (Staphylea colchica, Staphylea pinnata).
Damage and control
Mangold clamps are over-wintering sources of several aphid-transmitted beet viruses, and of several species of aphids including Rhopalosiphoninus staphyleae ssp. tulipaellus. Heathcote & Cockbain (2008) found that this aphid did not transmit beet mosaic virus, but was a fairly efficient vector of beet yellows and beet mild yellowing viruses. They did not find this species on sugar beet in the field, but felt that it probably spread these viruses from the clamps.