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Small blackberry aphidOn this page: Identification & Distribution Biology & Ecology Other aphids on the same host Damage & Control
Identification & Distribution
Aphis rubifolii lives in curled-leaf pseudogalls (see first picture below) of various species of blackberry (Rubus species). The adult apterae are pale yellow, mottled to a greater or lesser extent with green (see second picture below). Their appendages are mainly pale, but the tarsi and apices of the siphunculi are dusky or dark. The antennae of Aphis rubifolii are 5-segmented (cf. Aphis rubicola, which usually have 6-segmented antennae - except for the summer dwarfs of that species which have 5-segmented antennae). The antennal terminal process is 1.6-2.6 times the length of the base of antennal segment VI (cf. Aphis ruborum, which has the terminal process 2.5-3.6 times the length of the base of antennal segment VI). The cauda has 7-11 hairs (cf. summer dwarfs of Aphis ruborum, which have 4-7 hairs on the cauda). The body length of adult Aphis rubifolii apterae is 0.9-1.4 mm.
Images above by permission, copyright Claude Pilon, all rights reserved.
Aphis rubifolii alatae (see image below) have a dark thorax and head, and a green abdomen. Secondary rhinaria are confined to antennal segment III, and number from 2 to 7 (average 4). Their siphunculi are long and straight. The cauda is not constricted, and has about four hairs on each side.
CBG Photography Group, Centre for Biodiversity Genomics, under a Creative Commons 3 licence.
Image above by permission, copyright Claude Pilon, all rights reserved.
Small blackberry aphids live in crinkled leaf pseudogalls on both cultivated and wild species of blackberries (Rubus). On cultivated varieties they are often found near the tips of the blackberry canes. This aphid species does not host alternate. Sexuales with apterous males develop in autumn and they overwinter on blackberry in the egg stage. Hottes & Frison (1931) found that Aphis rubifolii was not usually very abundant in Illinois, USA, but Davis (1910) found it "very common in Illinois, curling and injuring the foliage of the cultivated and wild blackberry." The species is found widely in North America, but (so far at least) not in Europe. It has however been recorded from north-eastern India and Nepal, presumably as a result of an accidental introduction (Ghosh & Ghosh, 2006).
Other aphids on the same host
Aphis rubifolii has been recorded from 11 different species of Rubus (Rubus allegheliensis, Rubus cuneifolius, Rubus ellipticus, Rubus flagellaris, Rubus laciniatus, Rubus leucodermis (=Melanobatus leucodermis), Rubus occidentalis, Rubus procerus, Rubus strigosus, Rubus ursinus var. loganobaccus, Rubus villosus var. frondosus).
Blackman & Eastop list 4 species of aphid as feeding on Allegheny blackberry, common blackberry (Rubus allegheniensis) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 2 as occurring in Britain (Show British list).
Blackman & Eastop list 8 species of aphid as feeding on black raspberry (Rubus occidentalis) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 1 as occurring in Britain (Show British list).
Blackman & Eastop list 3 species of aphid as feeding on loganberry (Rubus ursinus var. loganbaccus) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 1 as occurring in Britain (Show British list).
Damage and control
Although Aphis rubifolii is not known to feed on strawberry (Fragaria), it has been cited as a vector of Strawberry Vein Banding Virus (SBVB) (Mellor & Forbes, 2011).