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Nipplewort aphidOn this page: Identification & Distribution Biology & Ecology Other aphids
Identification & Distribution:The aptera of Hyperomyzus lampsanae is whitish green. The antennae are mainly pale but with dark tips to the segments. The antennal terminal process is 7.8 to 9.7 times the length of the base of the 6th antennal segment. The apical parts of the femora are dark. The pale or dusky siphunculi are 1.5-2.0 times the length of the cauda and are markedly swollen, with the diameter of the swollen part of the siphunculus 1.5-2.6 times the diameter of the basal part. The body length of the Hyperomyzus lampsanae aptera is 2.5-3.5 mm.
The alate Hyperomyzus lampsanae has a dark trapezoid-shaped central abdominal patch, and dark siphunculi (see second picture above).
The clarified slide mounts below are of adult viviparous female Hyperomyzus lampsanae : wingless, and winged.
The ovipara is much like the apterous vivipara, but with the hind tibia swollen and bearing numerous scent plaques. The winged male is much like the alate female, but the abdominal patch is more or less broken up by pale areas, and the siphunculi are a little shorter.
The nipplewort aphid does not host alternate but spends its entire life cycle on the undersides of the lower leaves of nipplewort (Lapsana communis). Hyperomyzus lampsanae is common in northern Europe and in Russia.
Biology & Ecology:
Of seven aphid species commonly found on nipplewort, Hyperomyzus lampsanae is the only one that is restricted to this one host. Nipplewort (so-called because, either the closed flower buds, or the basal leaf projections were thought to resemble nipples - depending upon whom you believe) is an annual or perennial plant, often growing to about 1 meter tall, with small yellow flowers (see first picture below).
The larger leaves at the base of the flowering stem are often pinnate (see second picture above) and the undersides of these constitute the favoured feeding site of the nipplewort aphid. These leaves are covered with white glandular hairs which, most likely, have a defensive function against insects. Hyperomyzus lampsanae has evidently evolved its own way of dealing with these hairs.
The two pictures above show the immature stages of the nipplewort aphid - namely second-instar nymphs and a fourth-instar nymph. The adult is distinguished by possessing an elongate finger-shaped cauda protruding from its rear (see picture of adult below).
Hyperomyzus lampsanae sometimes forms large colonies on the lower leaves (see picture below).
Other aphids on Lapsana communis:Blackman & Eastop list 17 species of aphid as feeding on Lapsana communis worldwide, and provide formal identification keys. Of those aphid species, Baker (2015) lists 15 as occurring in Britain: Aphis fabae, Aphis gossypii, Aphis nasturtii, Aphis solanella, Aulacorthum solani, Hyperomyzus lampsanae, Macrosiphum euphorbiae, Myzus ornatus, Myzus persicae, Nasonovia ribisnigri, Pemphigus bursarius, Trama rara, Trama troglodytes, Uroleucon cichorii and Uroleucon picridis.
Bell et al. (2015) (Appendix S2) have also published an "annotated checklist of aphids present in the UK". We discuss some of the reasons for the differences between Baker's and Bell's lists in our rare aphids page.
These species do not occupy exactly the same niche as Hyperomyzus lampsanae. One such species, which we found feeding on nipplewort stems, is Nasonovia ribisnigri.
We have also found Myzus ornatus, a highly polyphagous species, often present in large numbers on the stem.
In addition to those listed by Blackman, we have found Neomyzus circumflexus. Again, these feed mainly on the stems of nipplewort (as shown below), not on the hairy lower leaves as Hyperomyzus does.