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Blackcurrant-sowthistle aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution:
Feeding by Hyperomyzus lactucae aphids on its primary host, blackcurrant, causes curling of the leaves and sometimes yellowish spots (see first picture below). The adult aptera (see second picture below) is medium-sized, broadly spindle shaped, and opaque green. The antennae of the aptera are quite long and pale, but the tips of the antennal segments are dark. The terminal process of the last antennal segment is 4.2-6.0 times the length of its base. The secondary rhinaria on antennal segment III of the aptera are clustered towards the base of the segment (cf. Hyperomyzus pallidus where they are more or less evenly distributed along the length of the segment). The siphunculi are pale with somewhat darker tips, 1.65-2.0 times the length of the cauda, and distinctly swollen. They are 4-7 times longer than the maximum width of their swollen part (cf. Hyperomyzus pallidus which has siphunculi 3-5 times longer than the maximum width of their swollen part). The cauda is pale, shorter than the siphunculi, and finger shaped. The body length of wingless adult Hyperomyzus lactucae is 2.0-3.2 mm.
The alate has a rather broken (fenestrated) central dark patch on the upper surface of the abdomen, shown in the third picture above and the second below.
The blackcurrant-sowthistle aphid has a sexual stage in its life cycle, and host alternates from blackcurrant (Ribes) to sowthistle (Sonchus). Populations build up on currant in spring causing leaves to curl downward and stunting young growth. Hyperomyzus lactucae migrates to sowthistle in June, disperses between the summer hosts in July and August, and returns to currant plants in autumn. The species is widely distributed in temperate parts of the world.
Other aphids on same host:
Hyperomyzus lactucae has been recorded from 31 Ribes species (including gooseberry, Ribes uva-crispa).
Blackman & Eastop list 22 species of aphid as feeding on blackcurrant (Ribes nigrum) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 14 as occurring in Britain (Show British list).
Hyperomyzus lactucae has been recorded from 13 Sonchus species.