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Spindle-nightshade aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Feeding by the aphid induces a crumpled leaf pseudogall on both its primary host spindle (Euonymus) and its most characteristic secondary host, black nightshade Solanum nigrum (see first picture below of pseudogall on black nightshade). Adult apterae of Aphis solanella are dull black or blackish brown, often with a reddish hue, and occasionally with white pleural transverse wax stripes. The longest hair on antennal segment III is 0.6-1.9 times the basal diameter of antennal segment three, in most specimens shorter than 1.5 times the basal diameter. The third antennal segment of the adult Aphis solanella aptera is 11-20 times longer than the longest hair borne upon it (cf. Aphis fabae fabae & Aphis fabae cirsiiacanthoidis where the third antennal segment is 4-9 times longer than the longest hair borne upon it). The dorsum has variable dark markings usually with dark sclerotic bands on the pronotum, mesonotum and abdominal tergites VII and VIII, and small dark marginal sclerites. They have marginal tubercles on abdominal segments VI and usually also on I (see first picture below), and sometimes smaller ones on some of the segments II-IV. The siphunculi and cauda are dark. The body length of the adult aptera is 1.2-2.6 mm.
Note: Until quite recently Aphis solanella was treated as a subspecies of Aphis fabae, but it is now accepted as a 'good' species. We have given some diagnostic characteristics to separate it from the various subspecies of Aphis fabae above. A further difference is that marginal tubercles are more often present on Aphis solanella, although about 40-50% of specimens still have no marginal tubercles on tergites II-IV.
The alatae (see first picture below) are dark brown or black with sclerotic dorsal banding more regular than in the apterae. The immatures (see second picture below) have a reddish-brown hue often with discrete white pleural wax spots.
The micrographs below show an adult aptera of Aphis solanella dorsal and ventral.
In Europe Aphis solanella has spindle (Euonymus) as its primary host. It can also live on mock orange (Philadelphus) and viburnum (Viburnum), but it does not thrive well on the latter. Oviparae are rarely produced on Philadelphus and never on Viburnum. Aphis solanella migrates to a wide range of plants, including many used by Aphis fabae, as well as black nightshade (Solanum nigrum) and black bindweed (Fallopia convolvulus). It characteristically crumples and curls the leaves of black nightshade. Aphis solanella will not move to bean (Vicia faba), beet (Beta) or poppy (Papaver), but it can be a pest on tomatoes (Solanum lycopersicum), potatoes (Solanum tuberosum) and peppers (Capsicum annuum). Aphis solanella is found throughout Europe and in Asia, Africa and South America.
Other aphids on same host:
Blackman & Eastop list 7 species of aphid as feeding on common spindle (Euonymus europaeus) worldwide, and provide formal identification keys (Show World list). Baker (2015) lists all 7 as occurring in Britain (Show British list).
We have restricted our listing of other aphid species on secondary hosts of Aphis solanella to the most characteristic secondary host, black nightshade (Solanum nigrum), albeit it has many other secondary hosts.
Blackman & Eastop list 15 species of aphid as feeding on black nightshade (Solanum nigrum) worldwide, and provide formal identification keys (Show World list). Baker (2015) lists 14 of these as occurring in Britain (Show British list).